# Cavers - The StenLight, Ultimate 2x3W LED Headlamp



## dar

Wow, I can't wait until the final production versions of this headlamp go on sale!

http://www.stenlight.com 

This baby has two 3W LEDs, fully regulated, one with a 15 degree throw for spotting, one with a fresnel lens for flood light. Uses custom rechargable Lithion Ion battery pack for light weight and great life, 5 hours on high, 20 hours on mid. Lamp is machined aluminum, *completely* water sealed...in fact, the switch is magnetic so no moving parts have to penetrate it.

Someone brought a pre-production unit to our local grotto meeting this week; we turned out all the lights and it lit an entire banquet room up. In fact, it's so bright, you'll need to be extra careful not to blind your fellow cavers with it. Looks like they're probably going to go on sale for around $310 with one battery and a charger...sign me up!

Edited: fixed URL, Firefox must be smarter than other browsers


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## John N

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*

Try www.stenlight.com, not stenlight.com.

The light looks very sturdy, but the hinge sure doesn't...

-john


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## RobWV

This looks like a great light for caving. Any idea when they will be available? I need to start saving my money.


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## PeLu

It was said to be in available in September, but no official statement AFAIK.
[ QUOTE ]
you'll need to be extra careful not to blind your fellow cavers with it

[/ QUOTE ]
That is easy with many lamps .-)

It should put out enough light for most caving purposes, still much less than a carbide lamp, anyway.

It cames close to the perfect lamp, the only feature I miss is that the two LEDs could be switched indepent. But this one would cause the price to raise too high.

We will also see if the magnetic switch does not influence the compass too much.

I like the Melzer Radon which is similar (but has just one LED) in practical life.


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## dar

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*

[ QUOTE ]
We will also see if the magnetic switch does not influence the compass too much.


[/ QUOTE ] 

I've talked to several people who have been testing the pre-production lights this year, all have been project cavers. Several I know personally have been surveying Hell Hole here in WV, and all have said that this light is the best they've ever used (yes, even carbide fans).

I agree that the hinge looks like a weak point from the photo, and I admit that I was too awestruck when I had the light in my hands to pay much attention to the hinge.


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## cue003

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*

Am I missing something here. Is there a headband for this "headlight" or is it only to be attached to helmets etc?

Thanks

Curtis


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## dar

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*

[ QUOTE ]
*cue003 said:*
Am I missing something here. Is there a headband for this "headlight" or is it only to be attached to helmets etc?


[/ QUOTE ]

It uses a standard blade mount.


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## Justintoxicated

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*

SOudns nice but way too Overpriced. 2 Lux III's are only $20 or less and te optics are onyl maybe $5.

So basicaly the rest of the money goes for the body and battery and circuit which are not worth it IMO. They could have at least used reflectors instead of carclo optics.


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## jtice

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*

Hi dar, welcome to the forums !
hmmmmm, David? that you? This is Trotto. /ubbthreads/images/graemlins/smile.gif

Thanks for posting about this,
I have been keeping in touch with the creator of this light, and it sounds very nice.

The switch uses a Hall effect design guys, 
so that should be great for water resistance.

I beleave there will be a bike attachment also, 
but it should be pretty versitile as far as what you can attach it to.

Justin, 
I have spoke to him about reflectors, 
I THINK that 17mm IMS ones will work in these, 
might require a slight spacer, but should work.
I think he went against reflectors due to optics allowing differnt beam patterns.

~John


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## jtice

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*

oh BTW, 

DAMN, they broght one to the last meeting. arg
I was out on my camping/caving trip then,
so I missed out /ubbthreads/images/graemlins/frown.gif

Think theres any chance they will be bringing one by again?


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## Justintoxicated

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*

sup Jtice, I been away fromt eh forums for too long, nothing new ehre though I'm still bitching about prices lol. Switch does sound like a good design.


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## jtice

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*

yea, you have been away too long, 
havnt even popped into chat to see me tisk tisk. /ubbthreads/images/graemlins/frown.gif

heh, im a price bitcher too, dont worry /ubbthreads/images/graemlins/wink.gif
I was hoping to see the price alittle lower also, but there was alot involved in this light.
and I think its very strong.


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## RobF

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*

I was wondering if a model could be seen anywhere. They're listing IMO (inner mountain outfitters) as a distributor but nothings yet listed on IMO's website. The stenlight contact listed is a non-functioning email address - at least it just bounces back to me.

I certainly like the small battery and after reading everything they've got on the site it seems to be a pretty decent machine. As far as i can tell it's in the upper end of caving lights and seems to be on a par with the HDS actionlight 3.

Anyone have any info on the stenlight's release date?
RF


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## jtice

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*

Rob, 

Yes, IMO will be selling the lights, I think in about 2 to 3 weeks from now.

Ill check into the email, and see if theres another that you can contact them with,

I have one sorta on preorder. and will be doing a full review on it.
As far as I can tell, its a step above the HDS headlamp, and ALOT smaller.

~John


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## jtice

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*

oh BTW, Rob, 

they are bases in VA /ubbthreads/images/graemlins/wink.gif
you should just find out if you can swing by to look at them. /ubbthreads/images/graemlins/grin.gif


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## jtice

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*

PM Sent Rob /ubbthreads/images/graemlins/smile.gif


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## PeLu

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*

[ QUOTE ]
*Justintoxicated said:*
SOudns nice but way too Overpriced. 

[/ QUOTE ]

Depends on what you use it for. I'm willing to pay for relyability and actually do not care about if the light costs $100 or $400 if I can expect 5 years of service from it. 

What I would like is that the two LEDs could be switched independently. So using a flood and a more spottish one, you could change the illuminated area. 
The lower light modes should be flood and vice versa.

Most of the time I prefer a pure flood light, but people's tastes are different.

The developer told me that this would almost double the electronics (of course) and drive the price out of many people's reach. Understandable.
Maybe there is sometimes a premium version....


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## jtice

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*

I also would have liked the option to have just one led on at a time.
But this would have added alot to the light, as far as the circuit, and would need a second switch.
The switch is just a crude metal tab, that you rotate, which is exactly what it should be for a caving light.
Sometimes you have gloves on, add some mud to that, and its hard to manages littel buttons and switches.

I think that the Stenlight comes with two 20 degree optics in it, 
I will probably have one flood and one spot in it.
Should make a nice bit of light.

Anyone know a good sorce for all the diff optics?
Didnt they have some that were really floody?


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## cy

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*

after reading the spec's, wondered why they chose to hook luxeons in series instead of parallel? 

redundancy is good.. if one fails, other would keep on trucking.


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## Floating Spots

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*

No Vf matching or grading in series.


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## niemidc

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*

A couple of quick notes from a StenLight designer:

- We shipped the first units to Inner Mountain Outfitters today, they should be in their stock sometime tomorrow.

- The production units have a fairly sturdy bolt-based swivel, not the rivet-based swivel we tried out on some of the prototype units. It weights an extra 5 g but we believe the extra sturdiness and the ability to adjust its tightness (and swap switch handedness) is worth it.

- The production models have one 5 degree lens and one 15 degree lens. It provides a pretty good general-purpose beam pattern, good for caving or outdoor use or bicycling. As PeLu pointed out, separate controls would be complex, not least of which being that we'd need to find a place to put the separate switches.

- Series connection of the LEDs permits significantly higher electrical efficiency and permits current regulation with one circuit. Wouldn't work well with parallel unless you had VERY careful matching; just getting LEDs from the same bin wouldn't be nearly close enough.

- As for redundancy, it is very possible for one LED to fail and the other to keep working when they are in series -- if it fails shorted or the circuit has a short, or even if you put one LED in backwards! The circuit will keep on working and still correctly regulate current to the surviving LED. We have actually tested this scenario. In parallel, if one fails even partially shorted it's totally dead, and if one fails open you send twice the current to the other, perhaps killing it too. So it's not intuitively obvious, but redundancy actually works better in the series connection when you're doing current regulation. Then again Luxeons are pretty darn reliable when you treat them right, and LED failures are probably not the most important thing to worry about.


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## PeLu

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*

[ QUOTE ]
*niemidc said:*As PeLu pointed out, separate controls would be complex, not least of which being that we'd need to find a place to put the separate switches.

[/ QUOTE ]

David,
could be done with a single switch, but thats to decide when the decision is made to design such a light .-)


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## niemidc

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*

Well, it could be done with a single switch and a CPU to keep track of what you're trying to tell it. But unless I'm missing something, that would be a totally different kind of switch.


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## jtice

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*

Hi niemidc, and welcome aboard! /ubbthreads/images/graemlins/thumbsup.gif

Series connection seemed the way to go on this one,
the redundancy adds to the reliability of the unit.

I am interested to see how the 5 and 15 degree optics work together.
Half the fun of this light, will be rounding up all the optics we can, and trying them all out! /ubbthreads/images/graemlins/smile.gif

Good to hear things are moving along, 
cant wait to order mine!

~John


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## Jerimoth

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*

Looks great, but for mountaineering and hiking, i wonder whether they will come out with a simple headband?


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## niemidc

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*

Yes, we do plan to produce a headband mount version in the future, but we don't yet have a schedule for it.


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## niemidc

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*

Another note: the StenLight is now up on the Inner Mountain Outfitters web site (http://www.caves.org/imo/LED.htm#S7). Hope that isn't too shamelessly commercial, but we've worked long and hard to get this thing on the market...


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## dar

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*

Sweet, just placed my order from IMO. $310 for the complete system (light, one battery, charger). $5 for a helmet mount (16-9802 L-2 Bracket) to fit my Ecrin Roc.

I'll be giving this baby a test run this coming weekend in Simmons-Mingo and My Cave (WV).

*niemidc:* Let me be the first to say "excellent job!"


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## dar

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*

Got my StenLight in the mail today! Unfortunately, IMO forgot to ship my helmet mount; argh.

- The hinge is different than the pre-production model I saw. It now has a threaded bolt and nut rather than two rivets. There's a plastic shim on both sides so you can adjust tightness with the bolt/nut and not have them loosen back up.

- It is *bright*! The regular setting is brighter than my Petzl Duo 7 LED on high, the high setting blows it away, and the turbo... The turbo setting lights up things in my neighbors' yards from my back porch, something none of my LED lights are able to do. The throw is very impressive. For once I expect to use a light at it's "regular" setting most of the time (rather than skipping regular for high like with a Myo or Duo).

- Negative points for the lack of a mounting system. I have to go through the trouble of buying a blade mount, drill holes in my helmet (which voids Petzl's warranty on it) to mount it. The blade mount on my helmet makes it hard to switch to a headstrap light for backup. The battery mounts with glorified velcro (adhering it to my helmet also voids Petzl's warranty)! Granted, this stuff (3M Dual Lock) is heavy duty, but I don't know how much of a shock it'll handle

More comments after I use it in-cave this weekend.


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## jtice

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*

dar,

Good to hear you like it, I shall have mine soon /ubbthreads/images/graemlins/grin.gif

I too would like to see more mounting options.
But they are planned int eh future I think.

I will be making some mounts for various things, including an attachment to my cameras tripod threading.

Curious, I have seen it two ways in photos...
does the cord plug directly into the Stenlight? 
or is there a perminate cord coming out of the light?

ah, BTW, you gonna bring it to the next Grotto meeting? /ubbthreads/images/graemlins/naughty.gif
I am plannign to attend the next one.

~John


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## John N

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*

[ QUOTE ]
*dar said:*
Got my StenLight in the mail today!

[/ QUOTE ]

Ahem! 

!?!?!?!PICTURES!?!?!?!?!



-john


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## PeLu

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*



> *dar said:*- Negative points for the lack of a mounting system. I have to go through the trouble of buying a blade mount, drill holes in my helmet (which voids Petzl's warranty on it) to mount it.



The blade mount is quite a standard among miners and cavers.

And how do you think original Petzl lights are mounted? 

(and BTW, I do not know anybody who ever needed a warranty with a Petzl helmet)


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## cue003

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*

Some pictures would be great! /ubbthreads/images/graemlins/smile.gif

Curtis


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## dar

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*

*PeLu:* I think blade mounts are a relic that do not apply to the modern headlamp. By modern headlamp, I mean an electric unit with battery attached to the helmet. A blade would only make sense here if one were used both in the front and the back of the helmet. It does make sense with a Carbide lamp or an electric with the battery waist-mounted, because the lamp need only attach to the helmet at a single point. 

When I talk about voiding the warranty on my Petzl helmet, it's not because I'm concerned with getting a refund on it! What I mean is that according to Petzl's warranty, they disclaim all responsibility for my brains coming out of my head if I drill any holes in the helmet myself, or if I apply any stickers or adhesives to it, presumably because the adhesive could weaken the plastic. This is the reason that new Petzl helmets have a textured finish rather than the old smooth finish, to keep people from putting stickers on them.

*jtice:* I brought it to the WVU Grotto's meeting last night to show it off. I'll bring it to Monday's Mon Grotto meeting so you can play with it if you haven't gotten yours yet.

BTW, I've had my Sten sitting on my desk pointing at the wall on 'high' setting for 4.5 hours now, and the spot has just barely diminished. The lamp is noticibly warm to the touch sitting in still air.

I will try to take photos of the unit this evening and post them here, though I won't have the time to do beam comparisons until sunday. I'll compare shots of the StenLight vs. Petzl Duo 8 LED vs. Petzl Myo 5.

Also, I found a compilation of comments from pre-production (pre-swivelling-hinge) beta-users surveying in Hellhole here: http://mailman.stensat.org/pipermail/stenlite-users/2005-May/000001.html


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## cue003

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*

Looking forward to those shots and also looking forward to Stenlight producing just a regular head strap for this beast. I will buy one today if it was available.

/ubbthreads/images/graemlins/frown.gif

Curtis


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## jtice

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*

dar,

I can understand about the helmet, but if your brains are oozing out your head, 
calling Petzl will not be toward the top of your list of things to do /ubbthreads/images/graemlins/wink.gif

Mod away ! /ubbthreads/images/graemlins/smile.gif thats what its all about.

It would be nice to have better, well, at least, more common mounting options right now,
but I think the blade setup is strong. at least I have heard...

Is it basically a slot, that the metal spade of the Stenlight goes in?

That would be great if you could bring it to the meeting,
I wont have mine by then, and I am dieing to check it out in person.

I imagine it gets really warm just sitting on a table, 
theres not really that much metal there to disapate teh heat,
though it does have builtin thermal protection, so it should be fine.
It should shut down if it gets too hot, or at least drop in output.

Thanks for the update.

~John


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## PeLu

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*

[ QUOTE ]
*dar said:*
*PeLu:* I think blade mounts are a relic that do not apply to the modern headlamp.

[/ QUOTE ]
And I think is is a good standard for interchangeability. Although it has it's limits, it works for most cavers. 
Yes, tastes are different.

[ QUOTE ]
When I talk about voiding the warranty on my Petzl helmet, it's not because I'm concerned with getting a refund on it!

[/ QUOTE ]
We just don't care too much, we explore caves instead .-)

As I prefer to run the cables inside the hardhat, I have to drill several holes anyway. 

BTW, how ist the battery pack covered? 
Does it look sturdy enough? 
I would like to have a pack with 4 cells.


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## cue003

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*

Hopefully stenlight will start working on the headband for this light so I can go ahead and get one to use as a "regular" headlamp and not on a helmet.

Curtis


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## jtice

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*

There are plans for bike mounts and headlamp mounts.
Though I do not know how soon we will see them.

I got to check out the Stenlight last night at the local Grotto meeting.
I have to say, it was hard giving it back to dar. 

Seems really nice, good fit and finish,
switch is robust, and could easily be operated with gloved, muddy hands.
Front SS bezel gave it a nice touch.

LOT of output per size ratio.

Weeakpoint, 
The battery pack and cable could be alittle more robust.
But this will be told with time, I should have mine within a couple weeks.
And plan to make my own battery packs for it. I am not sure how I want to handle the cables etc yet.

The cable, and pack are basically covered in thick shrink wrap.

I am thinking a velcro strap mounted on the back of my helmet, to strap around the batt pack. I also plan to run the cable inside the helmet.

~John


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## PeLu

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*

QUOTE=cue003]Hopefully stenlight will start working on the headband for this light[/QUOTE]

Just use one from another company. Speleo Technics, for example offers a headband for exactly this purpose.
Or cannibalize a cheap headlamp instead.
Or get the necessary spares from Petzl (as usual for Petzl., every single bolt is available seperate). 



jtice said:


> The battery pack and cable could be alittle more robust.


 Still not worse than Lupine.



> The cable, and pack are basically covered in thick shrink wrap.


Is there no additional cover over the cells?


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## jtice

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*

additional cover?
no, just looks like a couple layers of thick heat shrink.

Should hold up to most situations though,
but if you are wanting inpact resistance, there isnt any.

I would like to find some nice 4AA or 6AA holders to use with it.

~John


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## cue003

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*

It says above that this production light will use a 5 degree and a 15 degree optic. On the website fact sheet it lists something different....

"Smooth 20 degree beam pattern with other user-swappable lens options"

Are we still going to be able to change optics to match our desired function? 

Pelu, thanks for the suggestion. I will see if I can track one down. I am concerned about mounting the battery pack to the headband etc. I will have to find the right parts and try to put something together before buying this light. 

I have been on a big headlamp kick lately.

................ I just checked the Speleo website and did not see anything about the headbands being available for a "blade mount" separately..... hmm They are in the UK....I may have to call them.. Next I will check out Petzl.

Can anyone point me to the right parts to buy?

Curtis


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## jtice

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*

I think they say a 20 degree beam on that one page cuz 5 + 15 is 20 ??? :shrug:
Even though thats not how that works hehe

Yes, you can change the optics.
I am trying to find some optics for it, but not having much luck.
I can find tight beam optics easy, but cant seem to find any wide beam ones.
I place to do alot of experimenting with different optics, and maybe even a reflector.

I also plan to make a ton of attachments for it,
headlamp, bike, gun, camera, tripod, etc.

~John


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## PeLu

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*



jtice said:


> additional cover?
> no, just looks like a couple layers of thick heat shrink.



We used plastic house tubing (for plumbing), I don't know if it is still PVC, it is grey here and thermoplastic.
That means you look for an approbriate size of this tubing (inside diameter 33mm should fit) make it hot (glycerine, oil) and make it oval. 
If you do more than one, a wooden template (exp?) will help. 

This is what we did for other cells (SubC).

Headband:
Look at the NOVA's headband on 
http://www.speleo.co.uk/

If we can find out here what the StenLight's blade's inside width is...

They also have (had?) a headband which accepts a blade mount, I've seen it in (British) caving shops.


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## jtice

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*

PeLu,

Hmmm good idea, that would make it more impact/crush proof.
though I dont see why you really need that.
But it would protect from deep gouges though.


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## cue003

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*

Maybe Dar (I think that is who has one....) or Jtice when he gets his can provide us with the information on the inside diameter of the blade to help facilitate the search for an appropriate headband.

Pelu, 
will we also have to figure out how to mount the battery pack correct? 

Thanks.


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## dar

Sorry for not posting photos yet, I've been extremely busy this week. I'll give CPF some love early next week, after another serious caving trip this weekend. I've modified my helmet again with a strong strap that holds the battery in place on top the super-velcro so there's no chance of it falling. It's still not protected from being scrapped against a low ceiling though!

Someone asked about optics, from a quick visual inspection, the optics below appear to be the correct ones for the StenLight (two big ears, four internal "nubs" visible):

http://www.ledsupply.com/led-optics.html

ps. the new forums (hardware?) are so much more pleasant to use!


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## Ocelot

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*



PeLu said:


> I would like to have a pack with 4 cells.



Not gonna happen unless the voltage adds up to around 7V.

They went with two 3W Luxeons in series, and make use of a step-down regulator. The documentation mentions they did this for greater efficiency, and they quote numbers in the 85% range for step-up regulators. Of course, that is at full output. At lower output, which is where the light will be running 95% of the time, the step-up regulator will be much more efficient, and the difference won't be so much.

This is one reason I still make my own lights: I don't always agree with the design decisions made by others. By requiring a high voltage, you cannot use 4AA alkaline cells in a pinch. Well, perhaps at quite low output levels. But when caving in a 3rd world country, it's nice to know that you could buy backup batteries for your light if you run out of others or someone at the airport confiscates them (it has happened).

Scott


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## niemidc

A few notes from one of the StenLight designers:

The battery pack does have a layer of heat shrink on the outside. This is mostly for abrasion resistance. It's true that it does not have a hard plastic case (we may do that in the future when we get larger quantities going) but it DOES have pretty good protection for the batteries.

Outside the steel cases of the Li Ion cells, there are 3 thin layers of hard heat shrink, then 3 layers of rubber dip for waterproofing, THEN finally the outer heat shrink you observed. They have held up in caves well so far (including some prototypes without the outer heat shrink). We experimented with a variety of coverings, and believe we have a good tradeoff of bulk/weight vs. durability. In theory you could crush or dent them between two large rocks, but your helmet would be having discomfort by that point. I don't think scraping or gouging is a big issue; I've disassembled some of them and it takes significant effort to cut through all the layers of protection even with a sharp knife.

The blade on the StenLight is 0.75", and the inside bend is roughly 0.1". It fits every blade mount bracket we could find.

A fresh 4-cell alkaline pack or a 6V lead acid pack will work with the StenLight, but won't have enough voltage for full Turbo. Once they drop below 5V you won't get anything out any more. A 9V alkaline makes a good, compact backup battery for the StenLight (we're going to offer an adapter for this purpose). Of course, the ideal backup battery is a second Li Ion battery ;^)


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## PeLu

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*

4 cell pack



Ocelot said:


> Not gonna happen unless the voltage adds up to around 7V.


I was thinking about a 2p2s config, of course. Changing battery in cave is something I avoid. 

As it looks, the original pack is sturdy enough for most caving uses. I did the plastic tube trick for rotary hammer power packs, as these are sometimes treated not very carefully while transporting them.
This might also happen with spare batteries for the light, of couse it could be avoided with putting it into something else. 
In practical live it will just not always happen....



> They went with two 3W Luxeons in series, and make use of a step-down regulator....
> This is one reason I still make my own lights: I don't always agree with the design decisions made by others. By requiring a high voltage, you cannot use 4AA alkaline cells in a pinch. Well, perhaps at quite low output levels. But when caving in a 3rd world country, it's nice to know that you could buy backup batteries for your light if you run out of others or someone at the airport confiscates them (it has happened).



I would also prefer a lower input voltage, additionally there are no balancing problems with LiIon cells when you just use the usual 3.6V input.....

And use one of my numerous Li D cells I have at home and at one of these countries you mentioned above .-)


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## niemidc

The cells in the production StenLight batteries are EXTREMELY well-matched at the factory, and this is verified during QA testing. So I don't think balancing is much of an issue. If we were designing a low-power light, one Li Ion cell is hard to beat, but as power goes up it is advantageous to increase the input voltage.

One StenLight battery lasts through 2-3 long days of typical caving usage on a charge (mostly a mix of Low and Medium, with shorter periods of High and Turbo). Even if you use a lot of High you are unlikely to have to change batteries during a day of caving.

I do know someone who does a lot of video in caves on Turbo, and he uses large 7.2 NiMH packs instead; and some people use them off 12V; but for most people the standard batteries have plenty of capacity.


----------



## cave dave

I got to play with one at the IMO tent last weekend. Very, very nice. I like the switch a lot. Easy to tell what level its set at and change to another level with gloved hands, without turning the light off and then back on etc like some other designs. I can't imagine that velcro will hold the battery in place in a tight passage though.

Would like to be able to charge from my car. Caving usually involves camping somewhere without AC.

If they had the bike mount, and a car charger available I probably would have bought the whole package on the spot.  Instead I bought a custom cave suit (thanks Cecil)

As an aside its sort of hard to compare the light with the ActionLight 3, since that light is vaporware so far. It was supposed to show up at NSS Convention but did not. Nobody has seen one but Henry at this point and he's not sharing details.


----------



## jtice

Got my Stenlight today !!!!! :rock:

I had the pleasure of checking out Dar's before I made the purchase.
But now that I have been able to handle this one all afternoon, I LOVE it.

- I also like the switch, long travel makes it easy to tell what level you are on.
- The size is great, aLOT of light for a light this size.
- Hinge is nice and tight, there are some "plastic" washers that make it not slip.
- Slightly concerned about the switches slot, getting filled with mud.
But you can just wash it out with water anyway, the switch doesnt penitrate the casing. (hall effect)

I decided to make my own battery pack.
I am very firmilar with the 18650 lithium cells used in the Stenlights factory pack.
I used LG 2400 mAh cells, with a 7.2V protection circuit from batteryspace.com
The Triton charger will be taking care of the cells, though I would also like a car adaptor. I may at least get one of the 120V wall wart types from batteryspace.com and plug it into my 12V power inverter.

The protection circuit was shrink wrapped, then the open ends were sealed with epoxy. The cells were also shrink wrapped, but I forgot to take a pic of that :geez:

The clamp shell case is metal, so should provide alot of impact/crush resistance.
It was then epoxy sealed, except for VERY small places by the hinge.
This is was to let gas buildup excape.







I bought a few different metal and plastic blade attachments for the helmet.
But went with the metal one due to its low profile.
I wrapped some electrical tape around the middle of it to make the Stenlights blade fit real tight. Not that it would have fell of if I hadnt.






Please excuse the long bolts sticking out.
Those will be replaced later, I just used them to make sure this is how and where I wanted the bracket.





















I will be spending the next few days doing ALOT of testing.
I have a variety of optics and reflectors I want to try in the Stenlight, to get that perfert beam 
I might take beamshots using different types also.

I will have a full review of the Stenlight on my site, with better pics,
after a few weeks of hard testing :devil:

First Impression Conclusion? :goodjob: niemidc :rock:

~John


----------



## dar

Here's a minus for the StenLight's battery charger: 

If the charger is not plugged into an AC outlet, and a battery is plugged in to it, the charger's level indicator lights up green. 

I plugged a battery pack in, thinking my charger was plugged into the power strip below, saw green, put the battery in my cave pack. The battery was almost completely discharged. This could cause *serious* problems for someone. Luckily I brought a second battery with me. I wound up purchasing a cheap 12V inverter from Wal-Mart so I could charge the other battery in my car for the second half of the caving trip. Luckily the full battery easily lasted a 10 hour cave.

* I believe this charger should not light up at all if no AC power is applied! * I would almost understand if it served as a battery level indicator when not charging, but that's not the way it works. This should be changed for the second revision!

I wound up using the 'turbo' setting for in-cave photos, setting the exposure time long and "painting" with my light (a trick shown to me by CPF member jtice). This light had no problem lighting up the huge, 180 foot tall waterfall room in WV's Cass Cave.

Also, the super-velcro was not strong enough for my tastes, and I do not prefer to have the battery pack sitting unprotected on my helmet where I *will* scrape against low ceilings during crawls. I drilled a slot in my helmet and threaded a wide strap with clip around the battery to hold it very firmly in place on top of the super-velcro. Additionally, I fashioned a protective polycarbonate bumper plate to keep any corners or edges from rubbing rock. 

In spite of my small criticisms, this light is awesome! It has impressed every caver that's seen it so far... bikers too!


----------



## jtice

Hi Dar,

I saw some of the photos you guys took, nice work,
that drop into Cass looked sweeeeet.
Bet that wasnt fun going back UP though :green:

Well, I have been playing,,,, er ah, testing my Stenlight all night.
I replaced the stock topics with 2 25 degree optics.
But they are slightly different heights, so I have to put a couple layers of electrical tape one one side of the optic holder, and trim it to its shape.
That shimmed them up, nd made them fit tight against the lens.
Now its a much more flood beam.

oh BTW, Dar, you have mail ! 

~John


----------



## dar

Very interesting, check out these products from batteryspace.com:


http://www.batteryspace.com/index.asp?PageAction=VIEWPROD&ProdID=1199

7.2V 2400mah Li-Ion 18650 battery pack module with PCB (Protection IC)

This looks like the factory StenLight battery pack, minus thick heat-shrink and the connector. $22.95 from batteryspace.com, $50 from StenLight!


http://www.batteryspace.com/index.asp?PageAction=VIEWPROD&ProdID=1121

Universal Smart Charger For any 7.2V Li-ion Rechargeable Battery Pack

This looks identical down to the letter as my CL84-1 1.2V Li-ion Smart Charger, minus the connector. $18.99 from batteryspace.com, $30 from StenLight.


Both these products are cheaper in bulk. Who can find me a cheap supplier of the connector used on the StenLight?


----------



## jtice

Dar,

Those are the ones I used for my pack. except I used the 2400 mAh cells.
Same protection circuit though.

The charger is the same charger, but Stenlight put their connector on it.
Which can be bought from digikey.com page 120 of their catalog.

CAUTION !!!
Rechargable Lithium cell scen be VERY dangerous is not assembled and charged properly.
Make sure to contact me of someone else that have delt with them before,
before you try making your own packs.

~John


----------



## PeLu

dar said:


> If the charger is not plugged into an AC outlet, and a battery is plugged in to it, the charger's level indicator lights up green.



That also means that the battery is discharged in this case. Not good. As I wrote several times, I charge my caving batteries with a generator which is switched off sometimes in the night (usually later that I go to bed).

On the other hand, nothing is easier changed as the charger and I would just stick with my chargers anyway (they are 12V powered and use a wall wart for 230V). 
Lupine has some very nice and good chargers for 7.2V packs which are universal for 12V and 100-250V. And they tell you the charged capacity. But they are, of course, Lupine priced.

I want to change my Melzer Radon lights to this plugs, so I'm looking for a source of them, too.
Also I will make several emergency packs with primary lithium cells.


----------



## jtice

Well, I gave the Stenlight a pretty good test over the weekend doing some caving.

I am very pleased.
The 2 25 degree optics made a really nice flood, that was almost completely artifact free. 
I used the medium and high settings the most, and use low if we were taking a break to eat etc.

The switch is great, the large "handle" and long travel, makes it really easy to operate, and real easy to tell what level you are in by simply feeling where the switch is positioned.

After we got out of the cave, we walked down to the river to take a quick swim and clean up a bit.
I noticed that there was some dirt in the switch, and it was quite gritty to move it.
Being a bit concerned, I submerged the entire Stenlight in the river, and rotated the switch back adn forth about 10 times.
This flushed out all the dirt, and the switch was working smoothly again.

I hope to do a runtime test on my battery pack tonight,
which should be close to the ratings stated on Stenlights site, seeing how I used the same cells in mine.
Though, I am charging mine with the Triton charger.

The Stenlight can get pretty warm after about 15 to 20 minutes on high.
But it seemed to stabalize at a reasonable temperature. And it has thermal protection builtin to the circuit anyway.
I dont think there would be a problem leaving it on any setting you wanted.

~John


----------



## cue003

Can the LED's be upgraded in the Stenlight? I would like to use the more efficient K2 emitters when they become available to reduce the heat output etc of the light. I am a little more concerned about heat than most since I am going to use this light as a headlamp 99.9% of the time. I just need to piece everything together with appropriate head strap/battery holder and then buy this baby.

JTICE, looking forward to hearing more about the optic choices and possibly some beamshots of the different optics etc.


----------



## cue003

dar said:


> Very interesting, check out these products from batteryspace.com:
> 
> 
> http://www.batteryspace.com/index.asp?PageAction=VIEWPROD&ProdID=1199
> 
> 7.2V 2400mah Li-Ion 18650 battery pack module with PCB (Protection IC)
> 
> This looks like the factory StenLight battery pack, minus thick heat-shrink and the connector. $22.95 from batteryspace.com, $50 from StenLight!
> 
> 
> http://www.batteryspace.com/index.asp?PageAction=VIEWPROD&ProdID=1121
> 
> Universal Smart Charger For any 7.2V Li-ion Rechargeable Battery Pack
> 
> This looks identical down to the letter as my CL84-1 1.2V Li-ion Smart Charger, minus the connector. $18.99 from batteryspace.com, $30 from StenLight.
> 
> 
> Both these products are cheaper in bulk. Who can find me a cheap supplier of the connector used on the StenLight?



Great find on these parts. You may be able to find the connector(s) at an electronics supply store. I don't have a Stenlight but please keep us informed as to what you find.

Take your light with you and go to a store in your area and you should find the connector.

Curtis


----------



## jtice

Curtis,

You dont have to worry about heat,
the Stenlight has thermal protection, so it wont hurt itself.
I think it can run continuously on High, just not on turbo.

Yes, the leds can be swapped out, 
they should be no harder to swap out then most other mods we do.

I dont know about the K2s though,
I am hearing very mixed comments on them, they dont seem to be living up to their expectations, at least not yet.

The connectors are really nice,
I like the shape and design, I think I will be getting some soon, to use for other aplications as well.

They can be bought at www.digikey.com
page 120 of their catalog.

Ill try to do some beamshots some time of the different optics.
But it will take alllll afternoon. Sence its not as easy/quick as just unscrewing a round bezel.

~John


----------



## cue003

JTICE,

LOL on the heat.... I was more worried about my forehead and less the light itself. 

Do you think you got a good bin in the light? Did you get a good lottery pick as far as beam color on high AND low? Would the light benefit from a (2) UWOK or maybe even a bin like a TV1*.... some people seem to believe that the *V1* produces better color rendition outdoors. I have never owned one so I cannot comment for sure. 

What about even mixing 2 different leds in the light? Just some thoughts. 

Also thanks for the Digikey post. This will save me some money when I go to buy this light. It makes it much more attractive now with the cheaper (but same) components.

Lastly, I look forward to the beamshots.

Thanks again.

Curtis


----------



## jtice

I dont think it would burn you on high, 
make you sweat alittle,,, eh maybe lol

Depending on how you mount it though, its probably not going to lay against your head, the bracket is gonna hold it out alittle.

BIN? ah, yes, mines a good BIN 

The other one I tested before buying mine was nice and white also.

I dont think it really matters that much with this lights setup,
but I still like to have two of the same leds.

I notice that after I changed to the 25 degree optics, the color shifted alittle toward the yellow side, but not alot.

The color shifts just alittle to the green side on the lowest setting,
but this is very typical.

~John


----------



## benh

I'm keenly interested in this light, primarily for use as a bicycle light. I'm eagerly awaiting the handlebar and bike helmet mounts to become available.

I'm interested in performance comparisons to some of the higher end bicycle light systems, such as the Planet Bike Alias SC (15 watt Halogen, which is what I use now) and some of the Niterider systems, especially HID systems.

Especially attractive to me is the battery pack flexibility. If I can stick a 12v high mAh battery pack on this light, I can get bajillions of hours of runtime on Turbo mode, which would be outstanding for the kind of daily commuting I do where I'd really rather not be *having* to remember to charge the battery every night. And in that case, the added weight of an extended runtime battery isn't a huge deal.


----------



## niemidc

Based on our testing, the StenLight on Turbo mode is in the same brightness ballpark as 15 watt halogen bike lights.

12V and 14.4V batteries are perfectly normal for the StenLight, just make absolutely sure you get the polarity on the connector right. If you use a high voltage Li Ion with a protection circuit, you won't get any warning when the battery is about to quit (with StenLight's 7.2V batteries the light gradually dims for a long time as the battery gets low). So you should carry a backup battery and/or use a battery with a state of charge indicator of some sort.


----------



## dar

cue003: All StenLights that I have seen have a very beautiful white light. My Duo LED has a very obvious blue tint when spotting next to it. I have not noticed a color shift in either turbo or low mode. It appears that they took care to pick a good binned LED for this lamp.


----------



## jtice

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*

Did a runtime last night with my 2400 mAh 2x18650 battery pack.







419 Minutes (6.98 Hours) of solid FLAT runtime :rock:
I had a 120mm computer fan blowing on the stenlight during the test.
The Stenlight is thermal protected, and will lower its level if it needs to,
so I didnt really need the fan, but didnt feel my new light needed to sit there running hot if it didnt need to.
Also, I did not want it to thermal regulate during this runtime.
Though, I do no think it would have anyway, it seems to stablize after 15 to 20 minutes anyway.
I am not sure what the ripples are from toward the end, 
they are about 1 to 2 lux ripples. May have been testing environment.

Also note that the low lux rating is due to the 2 25 degree optics I have in it.
It is one huge smooth flood beam.
If you wanted throw, you could slap in 2 LP Fraen optics :duck:
Which I will have to try some time, that would make this tiny light a SCREAMER.

Needless to say, I am happy with that.
Just look at that regulation ! :rock:

~John


----------



## cue003

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*

Wow that is a really flat run.... and long run. Nice.

Curtis


----------



## gearfreak

niemidc said:


> Based on our testing, the StenLight on Turbo mode is in the same brightness ballpark as 15 watt halogen bike lights.



Was this thermal limited or its all out 140 Lumens? - I'm trying to judge how much light I would get on high compared to a 5 or 10W vistalite.

Looks like a great light though, soon as there is a bike headlamp mounts and wider lens ready, I'll be up for one or possibly two sets.


----------



## PeLu

gearfreak said:


> Was this thermal limited or its all out 140 Lumens?


Top of the diagram says level 3 of 4. That should be 45 lm.

I would like to see a version with one white and one amber or orange LED. Should be no real problem as they are in series. 

David, how will the regulator react if the ourput voltage is lower? Could it be possible to make such a light in the normal production run?


----------



## RobWV

This is a really nice caving light (I have actually seen it used underground). That being said, I really don't understand the excitement of using this as a bike light. For not much more than the price of this light you can buy a HID bicycle light, which ought to be about three times as bright. Albeit the run time of a HID light would be much shorter, how many people ride for more than four hours at night?

Again this is awesome caving light. If only my wife didn't think $300 is too much to spend on a headlight, but I'm working on her.


----------



## benh

It's not uncommon for me to ride for 4+ hours at night/in the dark, though some of that time will not be time when a light is needed. Plus, since I'm a bike commuter, I will often be riding in the dark for multiple days in a row, perhaps for an hour or an hour and a half at a time.

I'm also lazy and slightly forgetful. So sometimes, I forget to charge my batteries and have to revert to a crappy AA halogen or something for the evening.

So for me, a bright bike light (comparable at least to the 15w halogen I use now, preferably even brighter) with decent throw and a fair amount of flood and some seriously huge runtime is very attractive. Bottom line is that 2 hours of runtime is nothing special in a bike light used for commuting/urban riding, at least in my opinion.

Something with a super long runtime would also be really cool for randonneuring, assuming that they ever make LEDs legal for primary lighting in a brevet.


----------



## jtice

keep in mind, 
those runtimes are with a 2 cell lithium 7.2V pack.

The Stenlight can handle up to 18V,
so you could make a much longer running pack for it.


----------



## benh

That's part of why I'm really excited by this light. Super flexible (to my mind) battery options, so I can pretty much build a battery pack that meets my particular tastes. Pretty cool.


----------



## gearfreak

From my point of view I already have a HID setup that gives me 6hrs of light which is about 6hrs too short for most races I go in. Many adventure races will run through multiple nights without a chance to charge/change batteries

Add in the light weight and ruggedness of an LED setup like this and you can see why the interest for bike riding  .


----------



## jtice

I made the first mounting adaptor for the Stenlight today.
As I said before, I want to make one for a tripod, gun, handheld, bike, and anything else I can think of.

I sat here for quite a while, with a assortment of nuts, bolts, clamps, washers, etc. Trying to figure out the best, simplest, easiest way to mount the Stenlight to tripod threading.
I do NOT want to modify the Stenlight itself what so ever, for any of these mounts. and that was making it more difficult.
Then it hit me! Use the blade attachment thats used to mount the light to a helmet.

I simply tapped the top of the helmet adaptor to fit the 1/4" - 20 tripod threading, screwed the adaptor down onto the tripod, pressed the Stenlights blade into the adaptor, and there I had it!
I perfectly effective, yet simple way to mount the Stenlight to a tripod.

The battery pack attaches in a less elegant fasion, with a rubber band.
I might go all out and upgrade that to a velcro strap later. :devil:

Enough talk! Pics !


















The 2 25 Degree optics I have in there make it a wonderful room filling flood.
and on low it makes an excellent desk or bedside reading light.

~John


----------



## cue003

Jtice, very very nice indeed. Now I am waiting to see how you make a standard headlamp out of it.... don't forget a place for mounting the battery..... 

Be sure to posts pics when you get it done.

Curtis.


----------



## PeLu

RobWV said:


> This is a really nice caving light. That being said, I really don't understand the excitement of using this as a bike light.



Indeed. This is like other people make some of the finest bicycle lights and sell them as caving lights, too, where they are only mediocre.


----------



## niemidc

PeLu said:


> I would like to see a version with one white and one amber or orange LED. Should be no real problem as they are in series.
> 
> David, how will the regulator react if the ourput voltage is lower? Could it be possible to make such a light in the normal production run?



It is quite possible to use different LEDs, as long as they can take the same current. It could definitely be done technically.

Of course, substituting LEDs requires us to do some special handling.

I rather doubt that colored LEDs would be much fun in a cave, though. If they are the same color you'd have trouble telling what is what, and if they are two different colors the world would look like a badly converged monitor.


----------



## PeLu

niemidc said:


> I rather doubt that colored LEDs would be much fun in a cave, though. If they are the same color you'd have trouble telling what is what, and if they are two different colors the world would look like a badly converged monitor.



There are good experiences doing that. One caver I know (working at the source) used to cave with only amber Luxeons at a time almost nobody knew that they exist.

British cavers used a mixture of different coloured LEDs to get somewhat white light and gained about twice the efficiency at that time.

And there are white LED modules to replace incandescents which have white and amber LEDs in them. 

And many more examples. 

While most, if not all of these lights, show an uneven colour distribution when the target is a white wall, it turned out that it is no problem while caving.


----------



## dar

*StenLight Failure!*

Wow, my StenLight *failed* on me today!

I went on a scouting trip in a Tucker County WV cave today, pushing fast to see how far a cave went and searching for a second entrance. We have not had rain in about two weeks, so the cave was fairly dry, though there was still a good deal of mud involved. After pushing about 2 miles, we turned back to meet up with the survey party at the front of the cave.

I stopped to drink some water and flipped my StenLight to the low setting to avoid blinding the other caver with me. I flipped it up to medium, no change. Flipped it to high, to turbo, no change. The light was stuck in low power mode.

The website claims "if the switch is destroyed or the magnet lost, the unit defaults to the LOW setting". My switch sure did not seem destroyed, the magnet was not lost, and I was still able to switch it off. I was afraid that my battery was about to die, so I unmounted it, and mounted my Petzl Duo which led me back out of the cave.

As soon as I got home, I gave the StenLight a good soaking in the sink and scrubbed all the mud off it. The switch felt 'gritty' as it does when it gets grains of dirt down in the lever. Switching it back and forth under the water cleaned it out so that it is nice and smooth again. I plugged the battery back in...

It works perfectly again. It is sitting here next to me on high and has been for an hour, meaning it was not because of the battery.

I suspect the mud in the switch lever caused it to fail? Cave gremlins? Solar flares? What a disappointment.


----------



## Ocelot

*Re: StenLight Failure!*



dar said:


> Wow, my StenLight *failed* on me today!
> 
> I stopped to drink some water and flipped my StenLight to the low setting to avoid blinding the other caver with me. I flipped it up to medium, no change. Flipped it to high, to turbo, no change. The light was stuck in low power mode.
> 
> As soon as I got home, I gave the StenLight a good soaking in the sink and scrubbed all the mud off it. The switch felt 'gritty' as it does when it gets grains of dirt down in the lever. Switching it back and forth under the water cleaned it out so that it is nice and smooth again. I plugged the battery back in...
> 
> It works perfectly again.



Did it have a LOT of mud on it? Could it have been somehow internally thermally limiting the brightness level, and because it sensed it was too hot, wouldn't go above low?

Scott


----------



## Archangel

*Re: StenLight Failure!*

I don't know where the magnet is, but is it possible it couldn't sense it?


----------



## jtice

*Re: StenLight Failure!*

Whoa, sorry to hear about that David.

On my last trip I had alot of mud in teh switch, it was very gritty to move.
But it never failed throughout the cave.
After we got out, I submerged it in the river, and moved the switch a few times,
its nice and smooth again.

I dont see how dirt and mud could messup the switch, or the magnet.
But I cant think of what else it could be either.

Keep us informed how it does.
Ill keep an eye on mine also.

~John


----------



## jtice

*Re: StenLight Failure!*

oh, I just thought.

If it does it again, try disconnecting the battery pack, then plugging it back in, that might reset the circuit, if it was a circuit error.


----------



## jtice

*Re: StenLight Failure!*

Got around to doing some beamshots tonight.






Full size Image Here 

I had 2 25 degree optics in it the last caving trip.
I really liked the nice even wide flood.

I have the 25 + 5 degree setup in it now,
its a nice tradeoff, pretty good flood still, but has some throw.

The 15 degree optic is a wide spot, but its alittle uneven compared to the others.

Ill try the 25 + 5 deggree setup a while, if the spot doesnt bother me too much I might stick with that. But I tend to not like spots for headlamps.

Oh, BTW, the 17mm IMS reflectors wont fit 
They are a couple mm too tall.
I might try to shoten one to see how it works. :devil:

~John


----------



## The1930sRust

Hello! My first post on this Forum. I have been lurking for a few weeks, specifically this thread. I just purchased a StenLight and had a chance to use it this past Saturday. I posted a sort of trip report/review over on the NSS Forum, http://www.caves.org/phpBB2/viewtopic.php?t=150. I suspect some of you post there as well...

The same review plus some pictures of the Sten can be seen at http://www.pbase.com/darklightimagery/stenlight

I do have a few questions and comments regarding the Sten. 

The only thing I did not like at first was a strange dark shadow or "donut" that seemed to come from the wide angle (or left) collimator. It was very annoying, and reminded me of a shadow that may have been caused by the brim of my helmet (but it wasn't). Covering the left LED made it go away. That leads me to my next question.

If I wanted to change out the collimators (which it sounds like is easy to do) what is a good online supplier? 

Are the two as supplied 5/15? I was thinking of going 5/5. In all reality I'll probably just leave it alone, as I soon got used to the artifact and learned to stop worrying and absolutely LOVE my StenLight! In fact, I'm sorry I even quibbled over such a small issue.  

Now, about the power settings. I was of the mistaken opinion it had five distinct power modes, the last two being Turbo thermal limited and just plain balls to the wall Turbo. Now I see that is not the case. I think I have it figured out now. In Turbo, in an environment where thermal buildup would not be an issue (say outside in winter or maybe in a wet cave) do you get the full 140 lumens until such time as the limiting kicks in? Then I assume it drops back to 4-5 watt consumption or so? Further, if it were kept cool (below the thermal threashold) it would run at around 140 lumens for 2 hours? In a cave I just wondered what I was running at...


----------



## cue003

Very good write up and glad you are enjoying the light. The more great reviews that come in the more I am leaning to buying this light.

Interesting place you mounted the battery pack. It looks like most put it on the outside that is the first picture I have seen mounting on the inside of the helmet. 

Curtis


----------



## jtice

Welcome to the Forum Mr. Anderson 

Very nice writeup, and very very nice photos, you will have an email/PM on the way from me soon, we need to talk 

Yes, the Stenlight comes with a 15 adn 5 degree optics stock.
I also didnt care for the 15 degree optic, it seems to have some beam artifacts.
The 25 degree ones I am currently using look much smoother.

I got them here.
https://www.candlepowerforums.com/threads/90175&highlight=optics

A warning though,
you will have to shim the optic holding metal plate some. 
So that it holds the optics up high enough to engage the lens. If you dont they will rattle. 
I use a couple layeres of electrical tape on the backside, and trimmed it to shape, worked great.

The Stenlight has 4 brightness levels, but as you mentioned,
the turbo mode will run in two brightnesses, depending on the temperature.

I also thoought about mounting my battery pack inside the helmet, 
I tried it on the top (inside) but it made the helmet too front heavy.
I may try it on the top/rear on the inside though.
But I am also going to mount a backup light to it, so I will ahve to see how it all balances out.

~John


----------



## niemidc

*Re: StenLight Failure!*



Ocelot said:


> Did it have a LOT of mud on it? Could it have been somehow internally thermally limiting the brightness level, and because it sensed it was too hot, wouldn't go above low?
> 
> Scott



Thermal limiting isn't likely to ever take the brightness much below the High setting. The circuit is all analog, no CPU that needs resetting. The fact that it could go to Off implies that the magnet was OK; they are epoxied into the switch disc. Mud could only enhance thermal transfer; it can only interfere mechanically.

Some theories:

1) The battery was kind of low, but when it got a rest by being on Low or Off for a while it recovered.

2) The battery connection was loose, and couldn't handle the usual amount of current required for High/Turbo.

3) The magnet broke loose (possibly accounting for the "grinding" feeling), and could get moved over to the Off setting but wouldn't go over to the higher ones until your washing pushed it back into its normal hole.

If your lamp continues to misbehave please email us at the support email address and we'll get it taken care of. Theories 2) and 3) would both involve some simple repairs. Or it could be something we've never seen before.


----------



## niemidc

The1930sRust said:


> [...]
> The only thing I did not like at first was a strange dark shadow or "donut" that seemed to come from the wide angle (or left) collimator. It was very annoying, and reminded me of a shadow that may have been caused by the brim of my helmet (but it wasn't). Covering the left LED made it go away. That leads me to my next question.
> 
> If I wanted to change out the collimators (which it sounds like is easy to do) what is a good online supplier?
> 
> Are the two as supplied 5/15? I was thinking of going 5/5. In all reality I'll probably just leave it alone, as I soon got used to the artifact and learned to stop worrying and absolutely LOVE my StenLight! In fact, I'm sorry I even quibbled over such a small issue.
> 
> Now, about the power settings. I was of the mistaken opinion it had five distinct power modes, the last two being Turbo thermal limited and just plain balls to the wall Turbo. Now I see that is not the case. I think I have it figured out now. In Turbo, in an environment where thermal buildup would not be an issue (say outside in winter or maybe in a wet cave) do you get the full 140 lumens until such time as the limiting kicks in? Then I assume it drops back to 4-5 watt consumption or so? Further, if it were kept cool (below the thermal threashold) it would run at around 140 lumens for 2 hours? In a cave I just wondered what I was running at...



The recommended optics are L2Optics (similar to LumiLEDS that preceded them), and the factory optics are indeed 15/5. A good supplier for them is www.ledsupply.com. You'll need a 1/16" hex key to open the front, and it is at your own risk; in particular, we can't guarantee a water seal that we didn't assemble ourselves. Observe which way the window, gasket, and metal parts were inserted, it makes a difference; and of course make sure you do this in a clean, dry, cool environment.

We are all puzzled by the "dark donut" comment -- could you please explain what you're seeing in more detail?

There are indeed 4 brightness SETTINGS, but the Turbo setting can vary considerably in brightness depending on ambient temperature and the amount of cooling. "Full Turbo" is a full 7 watts, but as you use it for more than a few minutes in Turbo the lamp heats up and starts to do thermal limiting. Typically that would be in the 3-4 watt range, or about twice as much power as High. Thermal limiting is analog, not digital, so anything that cools the lamp will let it run with more power (it isn't a separate "mode"). In theory, thermal limiting could affect all brightness settings, but in normal temperatures High is only slightly affected and lower settings are not affected at all as they consume so little power.


----------



## jtice

niemidc,

The "hole" we, well, at least, that I am referring to is sligt dark patches in the flood beam.
You can see it somewhat in my photo above in the 25 +15 optics pic (upper right)
Notice the blobby part in the upperleft of the beam?

I noticed this the most when I was testing the optics one by one.
I used a test led so that I could use each one seperately, to get a better idea of it pattern.

All seemed smooth and uniform, except the 15 degree one, 
it just looked like a dirty lens or something, blobby.

Again, this is not a HUGE amount of artifacts we are talking about here,
but it is slightly noticable. and besides this is comming from the CPF flashaholics 
We are always after the perfect beam :grin:

I havnt used the the 25 + 5 degree combo in a cave yet, 
but I think I like it the best. You get a nice wide flood, which lights your feet alittle better, but you also get some throw from it.
I generally dont like headlamps to have a spot, I find it anouying when moving me head.
But, I found that I was having to flip the Stenlight to high and turbo more than I wanted when in big rooms/hallways, with the 25 + 25 degree combo.
So I think the 25 + 5 will make up for that, and make better use of the photons.

Davids switch problem is very odd.
I dont know what to think of it, even when mine was jammed with mud, it worked fine,
it just felt like chewing sand. 
Good thing is, niemidc and the rest of the crew seem to be great guys, and will get things straightened out if it does it again. :thumbsup:

~John


----------



## The1930sRust

Thanks John and Curtis. 

I've spent a good deal of time today tinkering (read: disassembling) my Sten S7. Wonderful workmanship. I'll post pictures later. I also plan on doing my own beam test later, after sundown. 

Managed to dig up my old collimator I bought last year for a project. I think it is a 10 degree model. Seems to drop right in. Preliminarily, it appears to eliminate the dark halo I saw while caving. 

http://www.luxeonstar.com/item.php?id=396&link_str=88&partno=LXHL-NX05

I also see the Fraen Medium Beam Lens, such as at 

http://www.luxeonstar.com/item.php?id=749&link_str=121::123&partno=FLP-HMB3-LL01-0

Not sure whether they'd work or not, or if they are the same as installed.

More to follow...

CG


----------



## cue003

Looking forward to more pics and beamshots.


----------



## niemidc

The1930sRust said:


> Thanks John and Curtis.
> 
> I've spent a good deal of time today tinkering (read: disassembling) my Sten S7. Wonderful workmanship. I'll post pictures later. I also plan on doing my own beam test later, after sundown.
> 
> Managed to dig up my old collimator I bought last year for a project. I think it is a 10 degree model. Seems to drop right in. Preliminarily, it appears to eliminate the dark halo I saw while caving.
> 
> http://www.luxeonstar.com/item.php?id=396&link_str=88&partno=LXHL-NX05
> 
> I also see the Fraen Medium Beam Lens, such as at
> 
> http://www.luxeonstar.com/item.php?id=749&link_str=121::123&partno=FLP-HMB3-LL01-0
> 
> Not sure whether they'd work or not, or if they are the same as installed.
> 
> More to follow...
> 
> CG



Thanks for the compliment, we put a lot of work into it.

The Lumileds collimators stick up too much in front, and the result is that you might crack the window and/or you might not be able to get a good water seal. The 10 degrees quoted on them is plus or minus 5 degrees, about the same as the stock "narrow" 5 degree L2Optics lens.

The small Fraen lenses are in the opposite direction -- they are loose. You could shim them to make them fit better. One of their models has a rather nice beam pattern.


----------



## jtice

Added a couple more pics to the Stenlight gallery,
might take some more tonight, any requests?
http://www.jtice.com/gallery/view_album.php?set_albumName=StenLight

Not ready to post the headstrap ideas yet.


----------



## The1930sRust

Just uploaded a few more pics. Probably voided my warranty (!) in doing so, but was able to appreciate the beauty of this device more.

http://www.pbase.com/darklightimagery/stenlight

I tried my other collimator, but it was about 1 mm to thick to fit. Guess I'll accept the unit as is and just learn to live with the donut artifact, which I forgot about after about ten minutes anyway. 

CG


----------



## cue003

jtice said:


> Added a couple more pics to the Stenlight gallery,
> might take some more tonight, any requests?
> http://www.jtice.com/gallery/view_album.php?set_albumName=StenLight
> 
> Not ready to post the headstrap ideas yet.



You know I am waiting on the headstrap ideas. You might want to make 2....1 for you and 1 for me.  Just be sure to include a place to mount the battery.

Going to go check out your pics.

Most of my pic requests will come when you have the headstrap complete. 

For now, maybe some outdoor shots compared to some known lights. Something at distance and something flood type.

Thanks.

Curtis


----------



## cue003

Niemidc, 

Could you tell us the place you get the size collimators that fit perfectly? Maybe even provide a 5/15 default combo and then additional ones for sale 5,10,15,20,25 for example.

I am sure there will be many who buy the light that will be interested in different collimators sizes... myself included.

The 25/5 on Jtice's website looks to be very promising. 

Curtis


----------



## jtice

CG, thanks for the pics.

I wasnt brave enough to take the switch apart. lol
But I see its not all that bad now, I wont be afraid to take it apart later if ai need to clean it now.

How does the power cable enter the light?
Whats the other side of the switch plate look like?

OR, does the cable have contact pads to the back of the light, so the cord doesnt penitrate either?

Curtis,
Yea yea, Ill get the headstrap done soon enough 
I have some parts on the way for it. 

oh, BTW, added some MORE photos.

~John


----------



## cue003

Jtice, 

I was on the Inner Mountain website (http://www.caves.org/imo/frames1.htm) and saw/read what looks to be a solution for our headband.... 

"17-2402 ProLite Headband $8.00
Adjustable elastic headband has blade bracket in front, elastic loop at rear for NiMH battery."

Not sure what that means but it has the blade bracket etc and the elastic loop in the back .... all for 8 bucks. According to the picture on the site there is no top strap. 

Just a FYI.

Also, from your pics etc where did you find that little tripod and the thing you mounted your light to in order to screw it on to the tripod?

Curtis


----------



## cue003

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*

I have totally forgot to ask a question to those that own this light. When it is mounted on the blade on the helmet, can you still reach up and tilt the lamp up and down or is it in a stationary position until you loosen the bolts etc?


----------



## jtice

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*

Nice find Curtis !!!!!

Heres the strap on Prolites site, 
http://www.proliteii.com/Products/mounts.htm
Seems to have the center strap, and that is a blade attachment.

Wish I would have seen that when I ordered from IMO 
eh, just gonna have to order again. :ironic:

YES, you can tilt the Stenlight.
The blade is attached with a bolted together hinge.






There are some type of "plastic" washer bushings in the hinge, so you can keep it tight, yet still move it.
And the nut is some sortof lock nut, it stays where you tighten it to.
Its VERY nice, and feels perfect.

~John

The white threaded tripod part I used is 16-9801 L-1 Bracket $5.00 on IMO's site.
I just flipped it upside down, and tapped a 1/4" - 20 tripod hole in it.


----------



## jtice

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*

eh, I misread your tripod question...

Heres here I got the tripods, 
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&rd=1&item=7536447462&ssPageName=STRK:MEWN:IT

They are really nice, the top tilt part will lock real tight.

~John


----------



## cue003

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*

John, thanks for the tripod info and also for the link. I did notice one thing between the two website that you may want to clarify before ordering. on IMO website it says the headstrap is for a ProLite.... on the ProLite website it says it is for ProLite II. The pictures of the straps are different on the 2 sites. 

IMO says elastic loop for batteries and the other site you listed specifically states 1.5 and 3.7 Ah flat pack batteries....whatever that means.

Resolution is upon us for the headstrap option. 

Next up will be finding optics that don't require shimming. Hopefully Niemidc will shed light on that.


----------



## jtice

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*

ah good point there Curtis, 
Ill have to clearify that.

Oh BTW CG, nevermind my question about how the cord goes in,
I took a second look at your photo and understand now.

I think I shall goto sleep now, and dream of wearing my Stenlight 24/7


----------



## The1930sRust

niemidc said:


> We are all puzzled by the "dark donut" comment -- could you please explain what you're seeing in more detail?



Yes. I first noted it when standing in a very wide 50 foot trunk, but with water wall to wall and a flat ceiling 6 feet high. The lamp had a great spot beam, but the wide angle "fill" light was edged by a ring of shadow. You can see it clearly in the image below:






Covering the 5 degree collimator made it go away (NOT the 15 degree as I had previously reported), so I am sure it comes from that side. 

This screen shot was taken only two feet from the source. It was really magnified in the cave! It just surprised me, that's all. I suppose I was hoping for a smoother transition between spot and incidental lighting. Like jtice says, it is just a flashaholic thing! I'd bet some tinkering with other collimators would solve it. Again, I got used to it pretty quickly; it is a very vey minor *****...


----------



## The1930sRust

After physically inspecting the two collimators in the StenLight, and reconducting my beam pattern test, I conclude the donut I am seeing is being caused not by the 15 degree lens, but the spot 5 degree lens. It is an artifact of the spot. I was under the mistaken impression it was caused by the 15 degree collimator. I think I may try a second 15, or even a 25 and see what happens.


----------



## jtice

hmmm odd,
I though the 15 degree one was the bad one.
That halo might be from the 5 one, but my 15 seems blobby for some reason.
The 5 looks nice with the 25 though. Evens it all out.


----------



## The1930sRust

That's what I thought, that the 25 might even it out. I ordered a 15 and 25. I wonder if the oval 5x20 could be modified to fit?

CG


----------



## niemidc

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*



cue003 said:


> John, thanks for the tripod info and also for the link. I did notice one thing between the two website that you may want to clarify before ordering. on IMO website it says the headstrap is for a ProLite.... on the ProLite website it says it is for ProLite II. The pictures of the straps are different on the 2 sites.
> 
> IMO says elastic loop for batteries and the other site you listed specifically states 1.5 and 3.7 Ah flat pack batteries....whatever that means.
> 
> Resolution is upon us for the headstrap option.
> 
> Next up will be finding optics that don't require shimming. Hopefully Niemidc will shed light on that.



According to Alex at IMO, the ProLite II headstrap fits the StenLight lamp and battery quite nicely. We are also working on doing one of our own, though we don't yet have a schedule for that.

As for optics that really fit -- look at L2optics (available from www.ledsupply.com). The 5 degree, 15 degree, and 25 degree variants all fit fine, as do all of the older LumiDrives lenses. However, the L2Optics 5x25 lenses (which are a really strange beam pattern) do NOT fit because they have a large protrusion in front.

And Carclo and the small Fraen lenses evidently fit but require shimming.


----------



## cue003

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*

Niemidc

Thanks for the info. I have everything I need now to put together my headlamp... well almost everything... just missing some funds. That will come shortly and away to the IMO website to place my order for the Stenlight package, extra battery and also the Prolite II headstrap as you specified. From there, bounce over to the ledsupply website and order up another 5, 15 and 25 degree optics. Lastly order up a tripod so you can mount your light when not on our head or if you want to leave it on and stationary. After that we wait.... It all shows up and its party time. :rock: :drunk:

Couple more weeks and I will have what is shaping up to be the best led headlight available.

Is there an auto charger available for this light? That will be the only missing piece.


Curtis


----------



## jtice

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*

ah great news niemidc !
Thanks for the info.

I'll have to order one then. Seems that its practically made for it 
I dont even think it says Prolite on it, so thats cool.


----------



## jtice

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*

My Stenlight Review is up ! 

http://candlepowerforums.com/vb/showthread.php?p=1098439#post1098439


----------



## The1930sRust

Excellent review, John. May I linky?

Also, I got my www.ledsupply.com collimators in today. I ordered another 15, and a 25. My screen beam shots can be seen at

http://www.pbase.com/darklightimagery/stenlight&page=all

Be advised these screen shots were made by a rear projection technique. The lamp was approximately 1 foot behind the screen and the camera about three feet in front. They are only meant to show beam pattern and artifacts. 

I just came in from outside (dark backyard), trying out the 15/15 and 15/25. Again, trade offs! I think I like the overall output of the 15/15. Great for big caves. However, for general caving, the 15/25 with its softer spread and wider periphery might be better...got rid of that 5 degree collimator halo I hated nonetheless!

CG


----------



## jtice

CG, 

glad you liked the review,
sure you can link to it 

Finding the beampattern per your taste was half the fun huh?


----------



## niemidc

A note to CG Anderson and JTice about beam patterns: we originally used a dual 15 degree pattern for caving because it is fairly nice and smooth and has a limited hot spot, good indoors and in small cave passages. But field testers concluded it didn't have enough "throw" for large passages, and they have been much happier with 15+5. Meanwhile bicycle testers had been given 5+5 and decided they needed more spread, and also ended up being happier with 15+5. So that's how we got where we are now.


----------



## jtice

The 15+5 beam isnt bad really, and I am sure it was a nice all around beam to use.

I just like headlamps to have a very wide flood, so that you can see your suroundings, and feet, etc.
But the 25+25 didnt have any throw, so I went with the 25+5, its pretty nice now


----------



## The1930sRust

There is no doubt in my mind whatsoever that the StenLight has undergone perhaps the best field testing of any cave light ever created. And, to boot, you even gave end users the ability to customize the output by changing out collimators. I am sure Sten went with the best generalized beam patters: 5/15. I may end up changing back to this for reach in my big cave. I don't like the artifact induced by the 5 degree however, but this is obviously no fault of Sten. There needs to be a better choice in 5~10 degree collimators at your disposal. 

To concur with John, the 5/15 isn't really bad, and only a discerning (read: picky) eye such as mine likely picked up on it. Maybe it was just my cave that brought it out. 

I like my 15/15 too!

CG


----------



## niemidc

The1930sRust said:


> [...]
> I am sure Sten went with the best generalized beam patters: 5/15. I may end up changing back to this for reach in my big cave. I don't like the artifact induced by the 5 degree however, but this is obviously no fault of Sten. There needs to be a better choice in 5~10 degree collimators at your disposal.
> 
> To concur with John, the 5/15 isn't really bad, and only a discerning (read: picky) eye such as mine likely picked up on it. Maybe it was just my cave that brought it out.
> 
> I like my 15/15 too!
> CG



Now that you and JTice have further explained the "donut" we see it too and understand what you mean. One of our other engineers believes the area of light outside the donut may be due to reflections off parts of the lamp, rather than the lenses themselves. Going to 15/15 or 15/25 increases the brightness farther out and makes it less noticeable.

We would love to have some good lens options in the vicinity of 10 degrees, but they just don't seem to exist as of yet. While we're wishing we'd like shallower lenses that let us make the whole lamp even smaller, perhaps made of glass so as to further improve optical properties. If we get up to production runs of 10,000 we can get custom lenses made. But that would probably be a non-caving version of the lamp.

Keep up the good work!


----------



## Mike Painter

niemidc said:


> But that would probably be a non-caving version of the lamp.



Except for the price this is very close to the idea I've had for some time.

A light that can be used with a variety of power sources in a variety of formats. It could be slipped onto a larger battery pack (like the streamlight vulcan) for many hours of use or clipped onto a more standard two or three cell type body.

If you do a non caving light EMS and the fire service would probably be interested.
In this case an AA adaptor *must* be available. On a wild fire the radios are driven by AA batterys and there is a "large but finite" supply of them. They are usually given out by the case. No other type battery is in such common supply.


----------



## Ocelot

Mike Painter said:


> If you do a non caving light EMS and the fire service would probably be interested.
> In this case an AA adaptor *must* be available.
> 
> ... No other type battery is in such common supply.




This is why my homemade 5W headlamp uses a boost regulator vs. buck: To enable use of 2-5 AA batteries.

Everyone makes different trade-offs in the design of their lights...


----------



## nethiker

I'll second the desire for a Fire/EMS version. That's one I'm looking for and drew my attention to the StenLight in the first place.


----------



## jtice

I got the Prolite headstrap from IMO today.

Not bad really for the $$$, but the front part is kinda cheaply made.
Its simply a plastic pad, with a plastic strip riveted to it, for the blade to slide in.
The Plastic pad is padded with some foam though, and the strap runs behind that, so theres a good bit between your head and the plastic.

The straps are good quality, the back battery pack loop is perfect for my pack, 
but may be Slightly loose for the stock pack.
That can easily be first though by sewing the strap alittle smaller.

I will be drilling out the rivets, and reattaching the blades strip, higher up on the main pad, right now, the Stenlights blade will stick below the pad over 1/4"
If I raise it, it will be flush with the bottom.

All in all, worth $8, 
but I look forward to what Stenlight can come up with.

and I knew better than to post without.... PICS ! :sick2: 



















~John


----------



## cue003

Very nice John. I see from the picture what you mean about the blade hanging lower than the mount. You will have to bring the mounting all the way to the top of the unit for the Stenlight blade to be flush it looks like.

I agree for the money, it can't be beat....especially since Stenlight does not currently have their own headstrap setup yet.

Curtis


----------



## jtice

OK, that, ,,,, Sucked. :ironic:

Ever start the "simplest" of projects, only to realize you are in DEEP :toilet: half way through?

The rivets did NOT want to drill out.
They would spin in the plastic, and even tried melting it when I tried taking the Dremel to it.
I finally got them out, but I mangled and knurled up the plastic a good pit.
I re riveted the strap all the way at the top, which now holds the Stenlight on there perfect. But my rivets are not really a great size for this, and it looks all haggard. :sick2:

I would not recommend anyone try this, unless you think you can get those rivets out nice.
I need to stop getting the urge to mod (destroy) everything I touch. 

OH WELL, the strap works, who cares what it looks light, (no Im not posting a pic),
now my Stenlight is even MORE useful. 

~John


----------



## dar

*StenLight Failure Revisited*

So I took my StenLight into a very nasty project cave in Mon County WV this weekend. The point of this trip was to dig some passages out, so I spent about 5 continuous hours in the medium setting. When I got out of the cave, I took my helmet off and unplugged the battery from the lamp, and...

...the StenLight's battery connector was hot to the touch. Inspection reveals that the metal contacts are of a duller grey color than the silvery color that I remember them being. While I have NOT had my StenLight in any seriously wet caves (and definitely never in saltwater), it seems very likely that moisture has caused some oxidation on the connectors, which seems to be causing some serious resistance.

Can any owners (or engineers) tell me if they experience heat from the battery connector? This is obviously wasted energy, but I'd like verification that mine is behaving abnormally.


----------



## Mike Painter

*Re: StenLight Failure Revisited*



dar said:


> ...the StenLight's battery connector was hot to the touch. Inspection reveals that the metal contacts are of a duller grey color than the silvery color that I remember them being. While I have NOT had my StenLight in any seriously wet caves (and definitely never in saltwater), it seems very likely that moisture has caused some oxidation on the connectors, which seems to be causing some serious resistance.
> 
> Can any owners (or engineers) tell me if they experience heat from the battery connector? This is obviously wasted energy, but I'd like verification that mine is behaving abnormally.



Assuming that the joints are not being heated from some other source this is not good. If they are soldiered on the problem is probably bad joints. They might discolor if a good joint but they should not be hot.

If they screw on it might be just because they were loose. 
It could also be the crimping or soldering is bad.

At that price gold plated terminals should be standard. They are cheap now adays.


----------



## The1930sRust

I would say that the point of connection is always going to be the Achilles Heel of any lamp rig. I am reminded of the Spelotechnics system; I sometimes had connection trouble at the battery due either to oxidation or weakening of the recepticle. 

That stated, I find it difficult to believe that Sten would use a standard (read non gold plated) Molex plug (or other device) if it didn't work well. Seems it got a fair bit of underground testing, and subsequent modification, in Hell Hole testing. But what do I know! I'm gonna keep an eye on mine. As someone opinied, is there a spray that can be used to reduce oxidation?

I have not noted any heating of the connection on my rig, but perhaps a burn-in test is coming. So far, the main problem I have heard of (three documented sources so far) is mud behind the switch plate causing the unit to become inoperable in at least a few power settings. It seems to have a fail safe built in, that it will continue to operate in low even if the plate is lost or destroyed. Recently, a pal of mine experienced similar difficulties in Webster Cave:

"As we started to make our way out of the cave I flipped the switch to turbo to see how much power was left. This was after 8.5 hours in the cave with it being on high for 80-85% of the trip. After maybe 30 minutes the switch was inoperable. I submerged it in water and work the switch. The first three settings came back in operation but it had a very gritty feel when the switch was operated. After another dunk the turbo setting came back but still gritty. My thoughts are there was mud in the switch mechanism and it dried from the heat on turbo setting rendering the switch inoperable."

Note that he says the switch was inoperable, not the light itself. I plan on carrying a spare parts kit (as available) and hex wrench in-cave with me. I don't think surgery on the Sten in a cave is a very good idea, and it would have to be an emergency situation I'd say to take one apart. Still, wouldn't be much more involved than working on a carbide lamp, and I used to have to do that a lot years ago.


----------



## jtice

Hmm, that could have been the problem that caused your Sten to malfunction the other day Dar.

Maybe one of the connections is bad, and barely making contact.
I have not noticed mine get hot, but I never really checked them either.

~John


----------



## Mike Painter

"As someone opinied, is there a spray that can be used to reduce oxidation?"
Automotive stores sell a variety of sprays and goos.

Gold plating usially solves the problem.


----------



## The1930sRust

Touché! :touche: 



Mike Painter said:


> "As someone opinied, is there a spray that can be used to reduce oxidation?"
> 
> Gold plating usially solves the problem.


----------



## PeLu

The1930sRust said:


> I would say that the point of connection is always going to be the Achilles Heel of any lamp rig. I am reminded of the Spelotechnics system; I sometimes had connection trouble at the battery due either to oxidation or weakening of the recepticle.


probably the latter one. The Speleo Technics use stainless steel contacts which work very well and have a very good reputation (in this case). The contacts of the belt mounted battery packs are very relyable, quite waterproof and easy to clean (just in case). But, of course, they need to be manufactured especially for these lights.

I used contact sprays with good success and many of my contacts, both for caving and on my bicycle. Also gold plating does not last forever, but stainless stell contacts will.



> I plan on carrying a spare parts kit (as available) and hex wrench in-cave with me.



I would change the bolts to standard ones. The Melzer Radon has for a good reason bolts for a flat screwdriver (Martin calls it 'SAK compatible')


----------



## Kevenater

I have a question(recommendation). This applies to the donut issue. darklight mentioned in his review that the donut appeared right at his feet, could this maybe be remedied by stenlight making a slight modification on the light, maybe tilting the side of the light that causes this donut(i dont remember which side it was) slightly downward, just enough to put the donut on your legs instead of at your feet and the ground? just a thought to maybe test. I havent saw this light in person so i can't really give an opinion, just thought maybe it'd be worth throwing out there for you guys who have the light. I imagine you guys know by seeing exactly where the donut appears, if this would be likely to help solve the slight issue maybe.


----------



## RobF

jtice said:


> I also thoought about mounting my battery pack inside the helmet,
> I tried it on the top (inside) but it made the helmet too front heavy.
> I may try it on the top/rear on the inside though.
> But I am also going to mount a backup light to it, so I will ahve to see how it all balances out.
> 
> ~John



Hey John,
I bought a Stenlight setup but haven't yet got a chance to try it in the field. My question might be a silly one...I mounted my battery inside my helmet at the back towards the top using velcro. I was wondering if there is any danger of battery meltdown, explosion, etc. that could possibly happen during some unfortunate caving trip. Having a helmet in the way of this occuring would offer some protection. Is there a remote possibility and would i feel the heat of this occuring beforehand? What do you think?
Thanks,
Rob


----------



## jtice

Rob,

Short answer, I think you will be fine.

Long answer.
Well there is allllways a chance that something could happen, 
maybe the pack could get hit hard, or crushed where the protection circuit and wire connections are.
It COULD cause the cells to shortout, and vent, Violently.

But the chances of this are very rare,
actually, I think theres less of a chance with it inside the helmet,
since the helmet will protect it and your head.

BUT, make sure that the battery pack will not come in contact with your head 
if you fall and hit your head. IE, make sure the hemlet wanted push onto your head enough for the pack to touch your head.

With my halemt, I think it would in the back, but not if i place it on top.

Hope that helped,
~John


----------



## Ocelot

RobF said:


> I mounted my battery inside my helmet at the back towards the top using velcro. I was wondering if there is any danger of battery meltdown, explosion, etc. that could possibly happen during some unfortunate caving trip.



You won't see me mounting any kind of a lithium battery inside my helmet... I've talked with various notebook computer engineers who still don't entirely trust them in laptops.

I've heard more than a few stories of lithium batteries burning down plants, catching fire in laptops, etc.

I once opened a rechargeable lithium to see what it looked inside. I found 3 fuses; there might have been more. So perhaps they have figured out most of the problems. In any case, the convenience doesn't outweigh the risks for me. All it would take is a falling rock to hit & penetrate the helmet/battery and short the battery for bad things to happen.

As far as the operation of your helmet, the battery will impair that. The space between the suspension and the shell is there for a reason; it's not a storage facility.

Scott


----------



## NewBie

Ocelot said:


> You won't see me mounting any kind of a lithium battery inside my helmet... I've talked with various notebook computer engineers who still don't entirely trust them in laptops.
> 
> I've heard more than a few stories of lithium batteries burning down plants, catching fire in laptops, etc.
> 
> I once opened a rechargeable lithium to see what it looked inside. I found 3 fuses; there might have been more. So perhaps they have figured out most of the problems. In any case, the convenience doesn't outweigh the risks for me. All it would take is a falling rock to hit & penetrate the helmet/battery and short the battery for bad things to happen.
> 
> As far as the operation of your helmet, the battery will impair that. The space between the suspension and the shell is there for a reason; it's not a storage facility.
> 
> Scott




I'd be really tempted to mount Li-Ion in a separate compartment from the one my brain housing group is in...that and a nice rip away mechanism, so I can holler grenade as I chuck them...


----------



## PeLu

Ocelot said:


> As far as the operation of your helmet, the battery will impair that. The space between the suspension and the shell is there for a reason; it's not a storage facility.



Thanks Scott for that comment. 
It is quite common that people put something into this 'empty' space, not thinking about that. The good old 4.5V square battery fit nicely into that space (and no other housing was needed). Other people carry some emergency equipment. And others have quite long bolts sticking inside. 
Fortunately we did not have any serious problems caused by that behaviour (up to now). 
They only thin acceptible inside there is a space blanket or a garbage bag. Both are compressible to a few mm is packed correctly.
Maybe a thin Li-Poly cell could be used that way one time.

Edit: One thing I forgot earlier:
I only accept cables and small connectors inside my helmet. I think I can justify them crammed into my head in the worst case.


----------



## rchrds

niemidc-


Hello- i have a question that has not really been addressed- I can only purchase lights that are truly waterproof- invariably they will be taken through sumps- often as deep as 100 feet- your case is so close to being perfect, but I am worried about the wiring bulkhead connection at the lighthead- I think I read that it was only waterproof to a few meters- what is your opinion on the depth rating- and any thoughts on improving the bulkead? (The battery is not a problem- Easy to build waterproof battery containers..._

J


----------



## niemidc

rchrds said:


> niemidc-
> Hello- i have a question that has not really been addressed- I can only purchase lights that are truly waterproof- invariably they will be taken through sumps- often as deep as 100 feet- your case is so close to being perfect, but I am worried about the wiring bulkhead connection at the lighthead- I think I read that it was only waterproof to a few meters- what is your opinion on the depth rating- and any thoughts on improving the bulkead? (The battery is not a problem- Easy to build waterproof battery containers..._
> J



Wow, those are some wicked deep sumps.

This is really not designed as a dive light, even though it has some features in that direction. There are a couple of problems with taking a normal production StenLight that deep:
1) the window might crack (I'd only trust polycarbonate under such extremes). The front seal would also have to be modified significantly to withstand that much pressure.
2) the rear seal MIGHT be able to take that much pressure, but we can't guarantee it. We have ideas on how to handle higher pressures in the rear if need be, but they're not practical for our normal production processes.
3) the connector would eventually corrode if it spends a lot of time plugged in underwater (and the battery side would corrode even if not plugged in).
By the way, for a previous poster, we looked at gold-plated connectors. They are only modestly better at withstanding corrosion in this sort of device -- the problem is you have a significant voltage across them.

I think we could probably do custom version that would meet your needs, but it would cost more. If you are serious drop us an email at [email protected] and we can discuss it further.


----------



## PeLu

I just want to add that the Stelight has the best hook so far holding it securely on a wide variety of brackets....

(And that I would like to have a version without any optics and a shorter housing therefore for a nice carbide-like floodlight)


----------



## jtice

Peter, You might want to try two 25 degree optics, makes a nice flood,
and will be brighter than just bare leds.

I have a variety of optics now, and I plan to take more beamshots comparing them all. Hope to get to that in the next couple days.

~John


----------



## PeLu

jtice said:


> You might want to try two 25 degree optics,


Yes, I will do that. There is shop nearby which should carry them. 

With the usual 5/15 deg optics it is no comparison with the Melzer Radon.

Without any optics (and an lambertian LED) is still the best for me. Even with a 25 deg optic you are only lighting up your own field of vision (partly).


----------



## jtice

Peter,

I would stick with a couple 25 degree optics,
I did some more testing last night, and its ALOT dimmer with no optics at all.
Granted, the angle is a good bit wider, but I find it ok with the 25 degree optics.







Note: The 6x25 optics actually project the beam diagonally.
I had to rotate the Stenlight 45 degrees to get that shot.
Its due to the Stenlights optics holder having notches in it for the tabs on the optics.
I suppose you could file the tabs off, and take the time to rotate them just right.

Overal, I like the 25+5 and 25+ 6 combos best.
I left it with the 25+6 this time, will try that out on my next trip.

~John


----------



## PeLu

jtice said:


> I would stick with a couple 25 degree optics,
> I did some more testing last night, and its ALOT dimmer with no optics at all.


Thnaks for the beamshots, but again, using one of the optics will loose lots of peripheral light (in this case much of it is lost due to the housing not made for it). You light just up your own field of vision and not the room. 
This is a completely different concept (or call it lighting philosophy).
Usual electric lights just illuminate the wearer's field of view (partly), we call them the egoistic lights.
Ceiling burner carbide lights, on the other hand, illuminate the room for everybody. That means everybody lights up for everybody. 
Of course this works only when all party members have this kind of light. And it changes the appearance of a cave very much.
And all I wanted to have was such a light combined with all the other Stenlight benefits. 
I have also some Melzer Radons, which make 80lm of flood light and like it very much. But they are not available any more.


----------



## whitmerm

Hi, I'm Mark and I'm a flashaholic.

I'm a long-time reader of CPF, but this is the first time I've posted.

This headlight is one of the most exciting lights I've read about. I had some thoughts about a different battery setup, and I wanted to run the idea past some people who know more about Li-Ion and ruggedizing than I do.

Even as good as the stock battery life is, I want more (doesn't everyone?). I don't really want to increase the bulk of the helmet, but I don't really want to install a hard, unforgiving battery pack inside the helmet either.

Then I ran across these:

https://www.batteryspace.com/index.asp?PageAction=VIEWPROD&ProdID=2169

Hopefully, that link will work. It's a 3.7V 6000mAh Li-Polymer battery. The dimensions are 7.5mm x 48mm x 168mm.

My impression is that these Li-Poly batteries are somewhat "soft", and given their thin form factor, I was considering putting 2 (or 3 or 4) of these in the crush-space inside my helmet. This would be a substantial increase in battery life with no additional bulk.

From what I understand, Li-Ion batteries need to be protected from overcharge/overdrain, and I assume something like the following would be sufficient.

https://www.batteryspace.com/index.asp?PageAction=VIEWPROD&ProdID=1247

The same place also sells a charger that works with 1 - 4 Li-Ion cells.

My questions are as follows:

1) Will this set my head on fire? Should I install a layer of foil or nomex between the batteries and the straps that contain my head?

2) I think my helmet will protect the batteries from most impacts and abrasions. How can I protect these odd-shaped batteries, the protection PCB, and the wiring between them from water? Obviously, a rigid enclosure isn't what we're looking for here.

3) Digikey sells molex connectors that look like the one used on the factory battery pack, but it doesn't explicitly state that the terminals are stainless steel like the ones StenLight uses. Any idea where I can get stainless ones?

4) Do battery used in series have to be matched in some way beyond just being the same model? If I used 4 batteries, would the efficiency be different with a 2p2s configuration vs. a 4s setup?

5) Are there any other glaring issues that I should be asking about?


Also, I've seen several people asking about how to protect the molex battery connector from corrosion while caving. Has anyone tried automotive dielectric grease yet? I used to use that on the ignition of my truck before playing U-Boat commander, and it seemed to work pretty well.

Thanks for taking the time to read all this. I look forward to reading your replies.

--Mark


----------



## jtice

Hi Mark, 
 
First off, Welcome to the Forum !!!!
 
Let me address a few things,
 
First, I also thought about some inside the helmet mounting,
but there are some problems.
You do NOT want the battery pack to be able to come in contact with your skull.
I can fit my batt pack in my helmet just fine, but if I were to fall and hit my head,
I think it would press hard enough to make it touch my head.
That would, hurt,



and it might damage the batt pack.
 
Also, your 3.7V 6000 mAh cells.... wow
thats alot of mAh




But, that thin flat shape could be bent easy I bet, 
DEFINATELY put them in a hard protective case.
Like a Pelican case, or Otter case.
 
Second, the Stenlight wants over 6V to operate properly, 
especially if you want all 4 levles of light.
So you will need at least 2 of those wired in series.
 
Batteryspace sells alot of protection circuits, just make sure you get the one
that is rated for that number of cells etc etc.
 
ok, now to your Qs.

1) Will this set my head on fire? Should I install a layer of foil or nomex between the batteries and the straps that contain my head?

I commented on the inside the helmet setup above,
But I would recommend, that if you do place them in the helmet,
make sure they are protected from the straps, 
Maybe heat shrink over the batt pack.

2) I think my helmet will protect the batteries from most impacts and abrasions. How can I protect these odd-shaped batteries, the protection PCB, and the wiring between them from water? Obviously, a rigid enclosure isn't what we're looking for here.

When I made my pack, I completely covered the protection circuit in epoxy.
So that water couldnt short it out, 
then I covered some of the wire connections to the cells.
WARNING: Li-Ion cells have vents on the Positive end for a reason...
they vent ! So you can NOT make a Completely air tight enclosure.
So dont go slepping epoxy all over the ends of the cells.
Also, if you use something like a Pelican case, dont seal it.
It should be ok during a day of use, but I would suggest opening it at the end of the day,
to let any vented gasses excape the case.

3) Digikey sells molex connectors that look like the one used on the factory battery pack, but it doesn't explicitly state that the terminals are stainless steel like the ones StenLight uses. Any idea where I can get stainless ones?

hmmm, Im not sure really,
I THINK the ones from Digikey are the ones used on the Stenlight.
I bought some from Digikey, and they look exactly the same.
(make sure you order the metal terminals with the connectors, they are not included)

4) Do battery used in series have to be matched in some way beyond just being the same model? If I used 4 batteries, would the efficiency be different with a 2p2s configuration vs. a 4s setup?

Yes, it is a good idea to match them.
There are a few opinions on how to go about this.
I think Li-Ion cells are easier, due to their Voltage reading closely representing their charge state, unlike Nimhs for example.
Heres what I did..
See if the cells V is closely matched when you get them,
if they are, great, wire it up, and discharge them safely,
then charge them back up, its best to charge them back up slowly,
but you may not have the equipment to do so.
I have heard you can connect the cells together somehow,
and they will balance themselves, but I am not sure.
Others should be able to help more with this.

5) Are there any other glaring issues that I should be asking about?

Yea, just how much runtime do you need !!! hehe
I tend to have mine on Medium in most caves, 
switching to high insome large rooms.
And even had it on low for the tight crawlways.
(always use as little light as possible to preserve night vision)
You can get DAYS of caving out of it like that.
I was doing 5 hour days just fine.
It seemed to easily handle 2 days like that, and might have done 3.
 
Hope that helped, 
let me know if you have any other questions.
~John


----------



## whitmerm

Thanks for the quick and thorough response. 



jtice said:


> Also, your 3.7V 6000 mAh cells.... wow
> thats alot of mAh
> But, that thin flat shape could be bent easy I bet,
> DEFINATELY put them in a hard protective case.
> Like a Pelican case, or Otter case.


Perhaps I'm wrong, but I was under the impression that the Li-Polymer batteries were somewhat flexible. I envisioned them conforming to the curvature of the inside of the helmet. If they do, I think there'd be enough clearance so that the straps wouldn't touch the batteries.



jtice said:


> WARNING: Li-Ion cells have vents on the Positive end for a reason...
> they vent ! So you can NOT make a Completely air tight enclosure.


Interesting. I didn't know about the venting. That rules out dipping the whole battery pack in that rubber/vinyl stuff. What type of epoxy is appropriate for coating the PCB? Where is it available?



jtice said:


> Yes, it is a good idea to match them.
> There are a few opinions on how to go about this.
> I think Li-Ion cells are easier, due to their Voltage reading closely representing their charge state, unlike Nimhs for example.


So the matching process is just making sure that the 2 batteries are in the same state of charge? That's not so bad. I was afraid I'd have to find 2 batteries with *exactly* the same discharge curve or something.



jtice said:


> Yea, just how much runtime do you need !!! hehe


Probably not that much. I figured it'd be good to have more than one battery pack, and I thought it'd be fun to build the 2nd one myself. If the 6000mAh ones will fit, I'll have a very comfortable margin of safety. 

--Mark


----------



## jtice

DAMNIT !!!!!!!!
I wish something would be done about the quotes locking up browsers AAAAAAAAAAAAAARRRRRRRRRGGGGGGGGGG!!!!!
 
ok,,, as I was saying... :ironic:
jtice goes to retype....


Thanks for the quick and thorough response. 

Perhaps I'm wrong, but I was under the impression that the Li-Polymer batteries were somewhat flexible. I envisioned them conforming to the curvature of the inside of the helmet. If they do, I think there'd be enough clearance so that the straps wouldn't touch the batteries.

hmm, I have never heard of actual flexible cells, 
that would be really cool if they are though ! 
Let me know if you can confirm that, and how flexible they are.

Interesting. I didn't know about the venting. That rules out dipping the whole battery pack in that rubber/vinyl stuff. What type of epoxy is appropriate for coating the PCB? Where is it available?

I THINK the Stenlight packs are dipped in rubber,
but I am not sure what portions of them are.
Also, I dont know if that would hold back the vented gas or not. 
Would be nice to know, I would like to use it if its safe.

So the matching process is just making sure that the 2 batteries are in the same state of charge? That's not so bad. I was afraid I'd have to find 2 batteries with *exactly* the same discharge curve or something.

Its not a big deal with Li-Ions,
due to the voltage representing the charge state real well.
Since you are buying them new, just get them the same voltage.
Now, adding a new cell to a 2 month old one is another story.
Then they would probably have diff. discharge curves. 

Probably not that much. I figured it'd be good to have more than one battery pack, and I thought it'd be fun to build the 2nd one myself. If the 6000mAh ones will fit, I'll have a very comfortable margin of safety. 

Oh, I am not saying it wouldnt be nice 
more is always better, especially if you arent increasing the packs weight/size much.
Keep us posted on how it goes !!!

~John


----------



## cue003

John, I am assuming the Lumidrives/L20pt etc mentioned above is the maker of the optics right? Where did you buy the 6 degree?

I know you had to shim the 25 degree version that you have, but did you have to shim the 6 degree as well? I still haven't gotten around to buying this headlamp yet. It is on my list ... just a matter of time.

Curtis


----------



## jtice

Yes, those are the manufactures of the optics.

They were sent to me for testing, 
so I am not sure where they can be bought, sorry.

Shimming,
well, I just left it shimmed for all those,
it seemed to work well, I didnt notice any holes, etc in the beams due to not being focused.

I have heard alot of optics actually look better sliiiiiighly shimmed :shrug:

~John


----------



## niemidc

To comment further on Mark's questions and JTice's answers:

JTice: it is all those Emoticons in the reply window that lock up your browser. I use Mozilla on Linux, and it pegs my CPU meter, I'm sure it's the same issue.

Our connectors are tin-plated, not stainless steel (stainless steel actually has rather mediocre electrical conductivity). Mark, dielectric grease is a really good suggestion -- I recently happen to have done an immersion test with it in fresh and salt water and it greatly cuts down the amount of current that flows (and hence greatly reduces the rate of galvanic corrosion). I'd recommend it for anyone planning on having their StenLight or its battery connection spend much time underwater.

Also at automotive supply stores, you can get electrical contact cleaners that should help to shine up the contacts. Probably a good idea if you already have some mileage on your connectors before you start using the dielectric grease.

That laptop battery is a lot of Li-polymer for the money. But it is BIIIG. I really doubt it is flexible, it is fairly thick. It is probably much harder than our stock batteries (not rubber coated). And you'll need at least two to get up to a reasonable voltage to power a StenLight. Might make a nice pack for a long pocket.

The vents on Li Ion and Li Polymer batteries (and most nicads and NiMH cells too) are only used in an emergency, like if you were to short it with no protection circuit or something equally traumatic. They don't vent routinely, in fact it is probably darn near impossible to make them vent while on the protection circuit. A hard, tight case covering the vents would indeed be a bad idea. Our case is more like a balloon -- it might puff up, and might pop, but rubber isn't going to prevent the vent from doing its job.

Cell matching is important if you want the battery to discharge in an orderly way and give you plenty of warning as they start getting low. If they are badly matched, one will still be sitting up at 3.3V while the other drops to 2.3 and cuts off the protection circuit for the whole battery, and your light goes totally dark suddenly. We had this problem in the prototype batteries, which were not well matched like the production StenLight batteries are. Also, if matching is poor you only get the lower of the two capacities, effectively. Definitely get two of the same type; but to get true matching you need to get something sold as a 2-cell battery, and even then you have to verify it.

And as JTice pointed out, it really isn't safe to put anything inside your helmet you wouldn't mind having pressed firmly against your skull. If it was truly small and flexible and flat, that wouldn't be so bad, but this is not a little battery -- in fact I rather doubt it would fit.

Welcome to the list! I am fairly new here myself.


----------



## PeLu

David and John: I too suffered from the browser lockup and I lost several long posts (some people might think: thanks god!)
And I never use (animated) emoticons and remove them even from the quoted text.



niemidc said:


> Our connectors are tin-plated, not stainless steel (stainless steel actually has rather mediocre electrical conductivity).


 That does not matter. The SpeleoTechnics lamps are one of the most relyable electric caving lights and use (custom) stainless steel connectors since decades. The connectors you use on the StenLight is probably good for some 30A, maybe more. The same in stainless steel probably for 10A. More than enough. In practical life I experienced that it is more important that the contacts are easy to clean and that some thin layers wear off. And stainless steel is easy to clean. 



whitmerm said:


> Even as good as the stock battery life is, I want more (doesn't everyone?).


 At least I do not want to carry more on my hardhat.

Putting a battery or a single cell into your helmet has the following drawbacks:
You decrease the crush zone. This might be OK if you use your hardhat mainly to protect the cave from your head (not making the ceiling in a cave bloody .-) That means in more or less horizontal caves.
This has been written in here before.
You also decrease ventilation. 
And there is not very much space. 
The helmet's balance will not be as good as with a back mounted pack (or better, depends).

IMHO the only thing inside your helmet (except your head) should be a space blanket or better a garbage bag. 

These LiPoly cells usually have a lower energy density than normal LiIon cells, but the one you mentioned comes close. 
They could be bent to some degree, but probably not enough for this application. 

I would go for 4 18650 cells, which will give a pack similar sized as the Petzl Duo's pack. How long will you stay on Turbo (I assume that it will work nicely in alpine caves). You could shape the four cells so that it fits perfectly to the back of your helmet. 

I don't really want to increase the bulk of the helmet, but I don't really want to install a hard, unforgiving battery pack inside the helmet either.

What I'm dreaming since more than a quarter century is a helmet which has a battery compartment built into the case, no additional weight and perfectly protected battery. I also know that it never will come true.



> I was considering putting 2 (or 3 or 4) of these in the crush-space inside my helmet.


4 of them will weight about 600g, more than a good helmet itself. 



> From what I understand, Li-Ion batteries need to be protected from overcharge/overdrain,


 It is good enough to leave the charge protection with the charger. (but it comes free with the protection anyway).



> Do battery used in series have to be matched in some way


You will need some balancing circuit anyway. I have batteries which were pretty well matched when new and drifted apart later. A balancing circuit has to be included in the protection. 



> If I used 4 batteries, would the efficiency be different with a 2p2s configuration vs. a 4s setup?


 The first one will be more efficient and you have some discharge warning. (with 4 cells in series you get the lowest capacity from all cells and the buck converter is slightly less efficient).



> Has anyone tried automotive dielectric grease yet?


 I use it all the time and I have mentioned it on CPF too many times already. Especially on higher current connections (we use lots of rotary hammers). It only collects mud. And runs away in hot climates.


----------



## cy

rchrds said:


> niemidc-
> 
> 
> Hello- i have a question that has not really been addressed- I can only purchase lights that are truly waterproof- invariably they will be taken through sumps- often as deep as 100 feet- your case is so close to being perfect, but I am worried about the wiring bulkhead connection at the lighthead- I think I read that it was only waterproof to a few meters- what is your opinion on the depth rating- and any thoughts on improving the bulkead? (The battery is not a problem- Easy to build waterproof battery containers..._
> 
> J



for diving....


----------



## jtice

wow, lots of comments sence I posted.
I will try to touch on all of them...

I dont know whats doing the lockups.
I know that alot of the time, if I use quotes in PMs they lockup,
but not all the time, :shrug:

Overal, I really like the 2x18650 pack,
its pretty small, and balances pretty nice when on the back of the helmet.
I havent really noticed that I am hitting it on anything yet.

I am planning on building a few packs, 
I like the small connectors, and plan to make other lights, etc run off them.
A 3x18650 pack might be the answer for you.
I plan on making one of those also, I think with one of those I could last an entire weekend.
The 2x18650 pack can last me a weekend now, but the added runtime of the 3x18650 pack would be very reassuring.

The thing I dont like about the thin cells you are talking about,
is the fact that I could probably take one in my hand, and break it in half.
The 18650 cells are going to be much more durable, and crush resistant.
I built mine into a hard clam shell, but I think they would have been fine just heatshrunk a few times.

David is probably right about the rubber coating.
Even though its covering the vents, its not going to be able to hold the gas back.
Though, AFAIK, they do vent with regular use, although very little.
(even open a freshly used light and sniff it?) :green: Its mainly with primary cells though.

I will have to look into that rubber dip stuff,
anyone know a good priced place to get it?

I have never heard of a balancing circuit.
Have anymore info on that?
My understanding was, that if you bought two new cells.
got them balanced well, that they should stay that way.

~John


----------



## gearfreak

jtice said:


> I have never heard of a balancing circuit.
> Have anymore info on that?


Not sure if this is what was being talked about- but I have come across these being advertised for model aircraft LiPo's 
Dualsky battery balancer 

And here is their blurb:
To 3S balancer for 3 cells pack (11.1v),the total volt value is settled to 12.6V,during charging, if the volt of one cell is over 4.25V,the balancer will begin to work, it will help the cell to consume the unwanted volt, but the other two cells are still charging. Once the total volt value is up to 12.6V,it will stop to charge.

To the first time using the balancer, perhaps you will find the volt of cells is different, but after 3 times or more, you will find the volt of cells is very close. So it can protect the cells not over charge and balance the cells volts.


----------



## whitmerm

jtice said:


> The thing I dont like about the thin cells you are talking about,
> is the fact that I could probably take one in my hand, and break it in half.


As far as rigid, candy-bar shaped batteries go, I agree with you completely. That'd be a very weak geometry for this application. They'd have to be enclosed in a pelican case or equivalent.


I think I found the source of my impression that these batteries are flexible. On this page:

http://www.batteryspace.com/index.asp?PageAction=Custom&ID=3#14

under the heading "What is the performance of Polymer Lithium ion battery?", they say "*Battery is transmutable and can be crooked: the maximum angle is 90[degrees]*"

Now, I've never actually handled one of these batteries, and much of the grammar on that page looks like it was poorly translated from another language, but my guess is that it means these batteries can be bent without damaging them.

I've emailed the company asking for more information. I'll post whatever I learn. In the mean time, does anyone have first-hand experience with these polymer Li-Ion cells?



jtice said:


> I will have to look into that rubber dip stuff,
> anyone know a good priced place to get it?


I can't find a link, but I remember seeing some stuff like that at Home Depot. It was in the section with electrician's tools. Basically, it was a can of goo that you could dip the handles of pliers in to give them a non-slip, non-conductive coating. I've never played with the stuff, but it looked like it might work here.

Anybody know where to get good abraision-resistant heatshrink?

--Mark


----------



## PeLu

I quote myself, it looks that my posts are too long and people do not read them .-)


PeLu said:


> They could be bent to some degree, but probably not enough for this application


90° might be a too general rule, a minimum radius would be more hlepful. Anyway, I think maybe they could be fitted around the back of the helmet, two of them and some case above. 

Balancing circuit: I do have several 7.2V packs containing 2, 4 and 6 cells and some of them came out of balance (after as few as 10 cycles). But I have to say that these were relatively cheap ones. IMHO a balancing cicuit is mandatory (actually I prefer lights which run on single LiIon cells, but sometimes there is no choice). 
I do have several packs I made for the Melzer Radon and use them now for the StenLight, too.
The problem is, people just say if a pack is 'protected' and do not tell what the ciruit is actually doing. Many of the cheap protection ciruits do unecessary things instead of the real stuff.

More than 2-cell LiIon packs: They have the big drawback that you do not have a warning when the battery gets low. This is absolutely mandatory for caving. There was quite some uproar when the SpeleoTechnics appeared with LiIon cells. Even when you say you are only using the capacity partly, one day the pack will not be charged in full (for whatever reason) and you experience yourself in the dark at an unpleasant spot. Been there, done that, survived with luck. If it can be avoided....

cy: I cannot see a stenlight on your nice cavediving picture....

BTW, SpeleoTechnics is using PU to encase their LiIon cells. They make a quite nice package out of one rectangular 6Ah cell. 



whitmerm said:


> Anybody know where to get good abraision-resistant heatshrink?


Try a bicycle inner tube instead (it is easy for me, I do have plenty of them in different sizes). I put one on the bare cells, then good shrink tube(s), and at last another layer of inner tube, which can be changed when worn. And you can put the socket underneath when not used. You might easily encase the whole battery in PU or similar amterial, in case the valve vents, it will not be another real resistance for the gasses. I do not know the actual values for LiIon cells, but with other cells the pressure for activation the valve is quite high. And the encasing material might keep the 'goo' in, also not bad. 
Heatshrink tubing: usually the one with the higher shrink ratio (1:3) is thicker and more resistant.

As mentioned above, I use several cheap packs for videocams. These could be bought at ebay for almost nothing. They have a a quite sturdy pastic housing, so I just have to make them waterproof and and add my unavoidable bicycle inner tube. Of course they are behind in performance to the original StenLight packs.


----------



## niemidc

gearfreak said:


> Not sure if this is what was being talked about- but I have come across these being advertised for model aircraft LiPo's
> Dualsky battery balancer
> 
> And here is their blurb:
> To 3S balancer for 3 cells pack (11.1v),the total volt value is settled to 12.6V,during charging, if the volt of one cell is over 4.25V,the balancer will begin to work, it will help the cell to consume the unwanted volt, but the other two cells are still charging. Once the total volt value is up to 12.6V,it will stop to charge.
> 
> To the first time using the balancer, perhaps you will find the volt of cells is different, but after 3 times or more, you will find the volt of cells is very close. So it can protect the cells not over charge and balance the cells volts.




The problem with this sort of balancer is that it only kicks in during the tail end of charging. If your cells are exactly the same capacity and different state of charge to begin with, it could help somewhat, but what is really needed here is a way to equalize charge near the bottom of the discharge cycle, which this device does not do.

In large batteries "flying capacitor" charge equalizers can actually redistribute charge between cells at any time. But that is not really practical in a small battery like ours.


----------



## niemidc

PeLu said:


> David and John: I too suffered from the browser lockup and I lost several long posts (some people might think: thanks god!)
> And I never use (animated) emoticons and remove them even from the quoted text.



I meant that the "Post Icons" section, that shows up as you are composing your post, can sometimes suck up a lot of CPU, and I thought it might be the cause of John's lockup.


----------



## cave dave

jtice said:


> Dar,
> 
> ...The charger is the same charger, but Stenlight put their connector on it.
> Which can be bought from digikey.com page 120 of their catalog...
> 
> ~John



John,
What is the Digikey part number for the connector? There is a whole page full on pg 120. Will need part numbers for both the female and male part. I figure I might as well get the parts before the light arrives.

-Dave


----------



## jtice

cave dave said:


> John,
> What is the Digikey part number for the connector? There is a whole page full on pg 120. Will need part numbers for both the female and male part. I figure I might as well get the parts before the light arrives.
> 
> -Dave


 Heh, crazy timing Dave,
I happen to have them right in front of me, I was making a few adaptor/cables, etc. just now.

You need 4 parts all together.

Connection Plug Housing = 03-06-2023
Connecting Receptacle Housing = 03-06-1023
Connection Terminals (female) = 02-06-1103
Connecting Terminals (male) = 02-06-2103

Dont forget some heat shrink 
About 1/2" dia. Before shrinking should work.

~John


----------



## SilverFox

Hello Mark,

I will jump in here and clear up some confusion about Li-Poly cells.

The cells are vacuum sealed in an aluminum pouch. The flexibility comes from the fact that they can be manufactured with bends up to 90 degrees. Once they are sealed, you can not bend them without compromising them.

Li-Poly cells have no protection at all. This requires the protection circuit to be mounted as close to the cells as possible. If the wires between your cell and the circuit were to short out, there is a very high possibility of the cell catching on fire in an explosive manner.

If you run bare cells without a protection circuit and your wires short out at the plug or elsewhere, you can easily end up with a puffed pack. If you are not quick to eliminate the short, it will catch fire even if at a low state of charge. 

The Li-Poly cells are sealed. When problems arise they puff up to 3 - 4 times their normal thickness. When designing a container for them, you need to allow for this expansion. Since there isn't that much room inside your helmet, I would recommend putting the battery pack somewhere else.

The aluminum foil pouch on the Li-Poly cell is fairly easy to puncture. If the puncture is just on the surface, it renders the cell unusable. If it is deeper, it shorts the separator out and you have a shorted cell with no way to remove the short. It will puff and catch fire.

Li-Ion cells are much more robust as they are in a tin can. They are also safer because even the unprotected cells have a PTC circuit that shuts the cell down in the event of a short.

Using cells in series is not a problem. The problems arise when you go to charge them. The safest way to charge is to charge each cell independently. If you charge in series you can run into cell imbalance. There has been much discussion about balancing cells in a pack. The general agreement (right now at least) is that it is OK for the cells to be unbalanced in a discharged state. Balancing is necessary toward the end of the charge cycle to keep the voltages on each cell below 4.2 volts. Some of the RC people have 70 - 100 cycles on their packs. They notice that the packs are not in balance when discharged, but come back into balance when charging. Others have had cells puff during the first charge, indicating that they were out of balance from the factory. 

I would recommend staying with Li-Ion cells, but if you want to use Li-Poly cells, I would recommend mounting the protection circuit right at the battery terminals. You could then dip the whole thing in plastic and drop it into your pocket... Just don't sit down hard... 

Tom


----------



## cave dave

I just got mine yesterday 
I also got the accessory kit. Anybody have any idea what kind of runtimes you will get on a backup 9v battery? Both Lithium and Alkaline. The Lithium 9v apparently have about 1200mAh. So theoretically you could get half the runtime as the stock battery.

http://www.batteryspace.com/index.asp?PageAction=VIEWPROD&ProdID=1618&HS=1

I like it so far, my first reaction was the low was too low, Its dimmer than a CMG infinity Ultra. If it was in the 6-8 lumen range I could see using it more. As it is I can only see using it for emergancy mode. Or while I'm not moving in cave. (sitting, eating, etc)

I'm a little disapointed that the beams aren't centered. All 3 I looked at were like that. The spot beam was not in the center of the wide beam. This makes it a bit spotchy and has a hole to the right of the spot beam. I put some writeright on and that helped with the spotchyness. It will also protect the lens. I'd try to adjust the optics but that would void the warrenty


----------



## cave dave

Well that last post seems a little negative. This light really is very very cool. I will say this looks like it will make a great little bike light as well. :thumbsup:

I'm sure it will evolve a little in the future. I hope they look into putting a reflector to replace the 5 deg optic. This will increase the throw and spill at the same time. Does anybody think one of the McLux reflectors will fit?


----------



## jtice

cave dave,

I have a nimh 9V batt,
its rated at 7.6V 150 mAh
and it ran the Stenlight for 1.5 hours on High !!!!!!!
I will be carrying that battery with me from now on for backup.

That cell you linked to looks very nice!
I might have to get one of those!

There are many optics that will fit the Stenlight, as you can see from my photos.
I have not found any reflectors that will yet.
The IMS 17mm and McFlood will not fit.

I had a tight 5 degree optics, and wide 25 degree optic in mine.
I think im gonna swap the 5 degree with a 15 degree for a while,
I like the throw, but I could have used a wide beam a few times.
So Im gonna try that for a while.

~John


----------



## cave dave

I've been running a 9v Alkaline on medium for 7.5 hrs now and its still putting out usable light. The hotspot is as bright as a Tikka+, although there is much less spill. My guess is about 9 Lumens.

Occasionaly I'll flip up a mode to see if they are still accesable
Turbo was unavailable after an hour
High disappeared sometime between 4 and 7 hrs

Very impressive :thumbsup:

i think I could do a short cave trip on just a 9v battery :wow:

I'd like it if they made a 3xCR123 carrier, It would be really light and small and the batteries are cheap off the net ($1.25ea) and pack plenty of power.


----------



## jtice

Wow, oo:

Thats awsome!
The heck with my crappy nimh one.
I will have an Alk 9V with me for backup from now on.

Thanks for the info !

~John


----------



## cave dave

More info on the 9v alkaline. I finally turned it off after 10 hrs on medium. At that point the medium (and all higer levels) was about 50% brighter than the Lowest setting.
I asked about 9v performance on the Sten light user group and David Nemi from Sten light replied:

"Based on watt hours, a 9V alkaline should last about a quarter as long as
the lithium ion on any setting below Turbo. That is, 1-2 days on low,
about 6-8 hours on Medium, and 1-2 hours on High. 9V alkalines have
trouble putting out near an amp so I wouldn't recommend using Turbo much,
but then the purpose of the 9V adapter is to give you a small, readily
available emergency backup.- DCN"

I have some Li 9v on the way and if they arive by next weekend I'll test them out in W.Va cave using med and high as appropriate and see how they do. They are rated at 1200mAh with a max output of 100mA. (but I'm willing to push it )


----------



## jtice

cave-dave,

hmm caving in WV? huh? what cave are you planning to see?

These 9V cells are gonna be GREAT backups.
I wasnt expecting this much runtime,
but then, I should have known, these Stenlights are are sooooo effecient. 

~John


----------



## cave dave

Ok I guess I could have bought a headstrap, but i didn't like the ones curently available. Stenlight hasn't released their's yet. Plus I have so many headlamps that are now obsolete so... 

Black diamond headstrap and the donor light:






Closeup, blade mount has been removed. I used plastic spacers and washers to space it out:





PS jtice, i sent you an email about caving in WVA
-Cave Dave


----------



## cy

don't know if this has been asked before...

any chance of a special cpf group buy on stenlight? 

I'm not a caver, so hard to justifiy $310
but if we could get a one time special cpf deal. more of us might go for it. 

cavedave, thanks for your pic. was wondering how I'd make stenlight into a std headlamp?

I've got a 18650 2x pack just waiting for this light.


----------



## PeLu

cave dave said:


> I like it so far, my first reaction was the low was too low, Its dimmer than a CMG infinity Ultra. If it was in the 6-8 lumen range I could see using it more. As it is I can only see using it for emergancy mode. Or while I'm not moving in cave.


Or while climbing a rope, or, or. For me the lowest setting is quite useful for many tasks and I would miss it it it would not be there. 
Even for narrow passages in white rock it is sufficient.


----------



## jtice

I love the low mode, and use it alot.

I have been in some tight crawlways, where my face is just a couple inches from the rock.
On medium it was blinding, low seemed just right.

I even used Low while hiking out of the woods once, it was just enough to see my feet well,
yet keep me somewhat night adapted.

cy,
I wouldnt count on a GB, I dont think there would be a sufficent number of ppl to make it worth while.

~John


----------



## paulr

All this modder battery pack stuff doesn't seem right for such a nicely finished product. I think it would be good to make an adapter for Sony L-series camcorder packs. These are solid little packs with up to six 18650's inside (NP-F960, 7.2v 6000 mAH, about $30 off-brand on Ebay). There's a wide assortment of chargers available for them (camcorder accessories). They come in three sizes (2, 4, or 6 cells) with the same mounting system and connectors, so you can just swap between them, i.e. use the 6 cell pack as a primary and the 2-cell pack as a backup. The 2-cell is maybe 2x the size of a 9 volt battery and is 7.2v 2000 mah or something like that. They even have microprocessors inside the pack so the camcorder can monitor the charge state, but I have no idea how the interface works.


----------



## jtice

Thats what I like about the Stenlights 6 to 18V input range, 
I can use all sorts of packs. 

These look nice, though I dont know how much I trust some off brand crap.
http://cgi.ebay.com/2-x-NP-F960-BAT...578781390QQcategoryZ48521QQrdZ1QQcmdZViewItem

Making the adaptor to hold the pack is what would be hard,
Finding an old camcorder, and ripping off the pack connection would be nice 

~John


----------



## paulr

There are some "universal" camcorder battery chargers with interchangeable connector plates to fit different kinds of batteries. The plates are about $5 each online (adoramacamera.com). I don't remember the part number. My idea is to use the adapter plate to connect the battery to the light (solder wires onto the other side of the plate). I haven't actually tried doing anything that way yet, so no promises.


----------



## jtice

I have a Triton charger, 
so I can charge pretty much any cell, pack etc I want.

I would just solder on a cord to the camcorder pack, and shrink wrap it.
I have all sorts of adapting cables I made for the Stenlights connectors, 
including ones for the Triton, so I could just plug it right in.

This would eleminate the adaptor plates, which can get wet and muddy,
then you will be in trouble.

I had an old 7.2V pack from an old digicam, 
that I wired a connector to, it was really nice, for the fact that the pack is already a hard shell.
But the pack was too old, and wouldnt charge 
it was sitting in storage at about 2V :shakehead:

~John


----------



## cy

just posted a feeler thread for a possible group buy for Stenlight. 

http://candlepowerforums.com/vb/showthread.php?p=1226852#post1226852


----------



## cave dave

I suspect trying to get the manufacturer to give a group buy on the S7 would like be like trying to get a group buy on a McLux PD. I seriously doubt it would happen. CPF is probably 50% of the market share. They seem to be setting MSRP and sticking to it.

PS The Dim setting is starting to grow on me.


----------



## jtice

For whats its worth, I have already been through this 

You are right cave dave,
For one, this would most likely be something one of their vendors would do.
There is a price fixing issue to think about, 
They produce a large enough # of them, and we wont want a large enough # of them
for this to happen.

dave, i think you will find yourself using the low mode more than you think 

~John


----------



## cy

hey, it's worth a try. if enough folks indicate interest. it may work yet. 

got to disagree CPF is 50% of the market. it's an awful big market out there. there's got to be loads of folks that's never heard of CPF. 

If someone else had posted a prior group buy on Stenlights. I would not be attempting to do this.


----------



## jtice

cy said:


> hey, it's worth a try. if enough folks indicate interest. it may work yet.
> 
> got to disagree CPF is 50% of the market. it's an awful big market out there. there's got to be loads of folks that's never heard of CPF.
> 
> If someone else had posted a prior group buy on Stenlights. I would not be attempting to do this.



Agreed,
we are big, but that that big 
The Stenlight is highly marketed to cavers, and they apreciatre light just as much as we do!

My last caving trip consisted of 13 ppl, 
5 of us had Stenlights  The other 8 wanted one 

~John


----------



## cy

don't forget about the cycling crowd, which is bigger than all cavers combined. 

24 hour racers would love to find a light that can accept a 6x AA pack. 2x 3watt luxeons is pretty low lumens as compared to a std bike light, but in a low light enviroment. more than enought light to operate with. 

Stenlight needs a better bike helmet mount. 

Anyone wanting to get in on the possible group buy, please indicate in the group buy thread. 

thanks,


----------



## gearfreak

cy said:


> 24 hour racers would love to find a light that can accept a 6x AA pack. 2x 3watt luxeons is pretty low lumens as compared to a std bike light, but in a low light enviroment. more than enought light to operate with.
> Stenlight needs a better bike helmet mount.



Ditto that for the adventure racers, I would have bought one in a second if it had of been built onto a strap rather than the blade mount. Seems as though that wasn't happening in a hurry I went the mod/DIY option.


----------



## jtice

gearfreak said:


> Ditto that for the adventure racers, I would have bought one in a second if it had of been built onto a strap rather than the blade mount. Seems as though that wasn't happening in a hurry I went the mod/DIY option.



Well, actually,
you can use the TwoFish Handlebar strap system.
( I think thats the name, there was a GB for them by GreenLED a while back )

Its a bubber peice, with two straps in it,
you simply take out one strap, and stick the Stenlights blade in the slot 

~John


----------



## gearfreak

I was more refering to a headlamp strap, and before any points it out I know there are some adapters out there, but they all looked fairly clunky and most non-cavers would prefer if it just came as a strapped headlamp option.


Thanks jtice though for pointing out the two fish gear- looks like some neat options for securing towrope setups and extra bottles for races.


----------



## cave dave

I'm actually a bigger cyclist than a caver or flashaholic. The cyclist have the DiNotte and Cateye double and tripleshot to choose from as well. I guess I was only thinking the flashlight and caver market. There aren't that many cavers, and most of the ones I know are cheap.

The triple shot MSRP is $320 about the same as a full package S7 and will most likely be available for less.
http://cateye.com/en/products/viewProduct.php?modelId=44&catId=7&subCatId=1


----------



## cy

there are a slew of lights available for cyclists out there. typically have much higher output than stenlight and 3-4 hour runtime. 

where stenlight would really shine is for the adventure racers and 24hr mountain bike racers. supporting a team of 24hr racer = lots of expensive batteries. 

stenlight with 6x AA option = cheap cells 
runtime would be way longer than most cycle specific lights. 
drawback would be less lumens than most halogen or HID cycle lights.

kinda surprised more folks have not indicated interest in the group buy thread???


----------



## cave dave

Generally the way a group buy works is someone contacts the manufacture or a distributer and finds out if a group buy is feasable and what the price would be for X number of units. Then they post the price and see if there is enough interest to meet the requirements.

I already have one of course, but if a group buy goes down I'll let my caving buddies know.


----------



## jtice

I took one of my Twofish handlebar straps, and modded it for the Stenlight.

All I had to do was cut off one of the rubber half loops.
Then insert teh Stenlights blade.
Works really well, and its bulky.















~John


----------



## cave dave

Is this for bike use? I found that two fish blocks let a light jiggle up and down too much unless the light is small light and well ballanced. With all the weight out front I bet it would bounce up and down quite a bit while riding. The only thing holding the blade in is a thin bit of rubber. I'm worried the rubber might tear. You might want to reinforce that area with some strapping tape.

-dave


----------



## cave dave

Inspired by Jtice's 2fish genius I decided to see what i could do.

I stumbled across this little beauty I bought over 10 yrs ago. It is a vistalite adapter to mount a beltclip blinky to your seatpost. The slot was just right for the blade mount. Its made of steel, rubber and webbing so its secure. (this item hasn't been made in years  )






I used a twofish lockbloc to mount the battery pack. The pack is 4pc, 18650cell, 7.2v @ 4500mAh: :thumbsup:

Can also be mounted to the frame.





This mounts the light vertical. It will tilt left, right, up and down. This is an advantage on Riser bars where you need to tilt in x and y axis so that you can get it pointed where you need it. It is easier to access switch if you put switch on top, but the wire routing gets tricky with all the other housing in the way.

I'll try it tonight to see if it jiggles.





*Edit* - Did I mention that the S7 anodize matches my Ti frame quite nicely


----------



## anachron

cy said:


> don't forget about the cycling crowd, which is bigger than all cavers combined.
> 
> 24 hour racers would love to find a light that can accept a 6x AA pack. 2x 3watt luxeons is pretty low lumens as compared to a std bike light, but in a low light enviroment. more than enought light to operate with.
> 
> Stenlight needs a better bike helmet mount.
> thanks,



DEFINITELY agree with the above 100%. I don't cave at all; my primary uses for the Stenlight will a) bicycle headlight and b) general purpose work-light (I do network & phone wiring installation.)

I notice that the MFG has been 'planning' to do a head-strap and bike handlebar mount for some months now, please accelerate that process as it will open your light up to competing directly in the comparatively huge bike-light market.

The main feature I'm sold on (aside from great build quality, durability, etc.) is the ability to use almost any battery pack.

As a do-it-yourself and early-adopter I'll probably just buy one as-is and jury-rig my own headstrap and bike handlebar mounts but it sure would be nice to see them available directly from the MFG. 

-A.


----------



## photonhoer

I have been able to get my hands on one, and it is a really well-built piece of equipment. 
However, in some low-tech, on-the-wall tests, the StenLight does not really outshine the PT Apex. The Apex beam is quite visible on top of the StenLight beam, even in Turbo mode, which the StenLight cannot sustain long due to its thermal limiting — suggesting to me that the Apex is at least marginally brighter in terms of central 'throw'. 
The StenLight beam seems much smoother (none of the rings in the Apex) and outdoors has more spread (spill) and subjective sense of overall illumination (again Turbo mode). In High mode, the Apex seems just about as bright and illuminating, but the StenLight has a MUCH longer run time on a set of standard batteries (AA alkaline vs. LiIon.)
One can buy a lot of AA batteries for $250.00!!


----------



## jtice

Remember, the Stenlight has swappable optics 
A couple 5 degree optics throws more, but you loose spill.

I like mine setup now, with a 15 and a 25 degree optic.
But, I tend to like a flood beam for headlamps.

~John


----------



## cave dave

You can swap the optics on an Apex too.


----------



## jtice

cave dave said:


> You can swap the optics on an Apex too.



Ah, did not know that, very nice.

I would like the option to run just one led on the Stenlight.
But I really like the dual led setup,
makes the beam possibilities alot more versitile.

~John


----------



## PeLu

jtice said:


> I would like the option to run just one led on the Stenlight.


Why? To have an option to change the light angle? We have discussed that already. Independent switching of the two LEDs would significantly increase the complexity and make it much more expensive. I doubt if people are willing to pay (only for example) $100 more for that option (I would, but who else?)
Switching beam widths could also be done with diffusers, not so elegant, but working (yes, I know the drawbacks).

Especially for bicycle lighting, the light distribution is far from beeing ideal for road use (suitable for off-road use).


----------



## jtice

Yes, mainly just to be able to flip from the flood beam, to more spot, etc.
Not a big deal though, the Stenlight is so efficient on the 18650 packs, that is doesnt really matter.
It would end up adding alot to the light, both in complexity and cost,
and probably wouldnt bo worth it in the end.

I nice defuser cap, that would fit over the light would be GREAT though.
It would also serve to protect it during transport.

~John


----------



## photonhoer

Cave Dave - please amplify on your Apex "swap optics" comment. Mine has MAJOR bands of dark and light, especially noticable at 30-40 feet, and I would love to smooth those out. thanks.


----------



## cave dave

photonhoer said:


> Cave Dave - please amplify on your Apex "swap optics" comment. Mine has MAJOR bands of dark and light, especially noticable at 30-40 feet, and I would love to smooth those out. thanks.



Do a search on Apex in thread titles in CPF, people have put both reflectors and optics in thier Apex.


----------



## PeLu

I have now prepared my lights for the next expedition. 

I have changed the Stenlight and the Melzer Radon to much smaller connectors (BEC from RC models) and yes, I'm well aware that these may also have drawbacks .-)

I covered my batteries in old bicycle innertubes and then in a very thick and soft shrink tube. Over that I put another short piece of inner tube. I put the connector an cable under this short tube (looks like a wider rubber ring) to protect it when not in use. 

I also made a 9V battery adapter, which also includes two pieces of bicycle inner tube which fits nicely around the battery and makes it soemwhat waterproof. Actually I could seal one end, but didn't do so up to now. 

Further I soldered 3 CR123 cells together for a better emergency battery. And covered it as above. Should last twice as long as the 9V battery, maybe longer.


----------



## Ralf

Peter,

is there any chance to see some pictures of your equipment
used at your upcoming expedition? 

Cheers
Ralf


----------



## JonSidneyB

For those that are not aware.

There is a Group buy for this light going on in the Group Buy Section of cpf right now.


----------



## Boricle

Does anyone knows if the Li-ion Charger supply voltage / cycle compatability is? Australia has 240V / 50Hz.

Most laptop chargers and similar are usual world voltage compatible - all that needs changing is the plug (and from the looks of the picture, a standard figure 8 style plug will do).

I've had a look at the Stenlight web site, through the FAQ, Fact-Sheets, Checked out Trotto's Reviews and Flashlight reviews and just plain couldn't see anything about this area.

Cheers,

Boricle


----------



## cy

li-ion charger is made for USA spec at 110V. look into if adapters are available for your local voltage.

most any li-ion intelligent li-ion charger will work, once you get setup with correct connectors. Triton would work great.

stenlight charger delivers 1amp to 2x 18650 pack and has an intelligent cut-off. but you still should not leave battery plugged in after charge indicator changes.


----------



## JonSidneyB

PM sent to Boricle.


----------



## Frenchyled

Thank you for the information Jtice !!
Ok, so I'm still in for a complete StenLight set + Parts Kit + accessory Kit !!
I would be really interested by a head strap, because I am not a cavers and I want to use my Light for night fishing without helmet 


Edited...Oops..I post in the wrong thread  Sorry I wanted to post in the G/B thread....


----------



## flashgreenie

I also got this charger problem since I am in Europe but I got a Schultz charger


----------



## Boricle

Thanks Cy and JonSidneyB.

I suspect that the charger world voltage may be okay. The charger shown on the Stenlight site: http://www.stenlight.com/img/charger.jpg

Looks similar to these two: with a label added to the Sten Light charger with the serial number on it:

Mega Batteries (although I've never dealt with them before and only found them by searching for 18650s) http://www.megabatteries.com/item_details.asp?id=11293&cat_id=51.

and 

Powerizer (same, never dealt with them)
http://www.batteryspace.com/index.asp?PageAction=VIEWPROD&ProdID=1256

These indicate that those chargers are world voltage compatible (but don't have the Stenlight molex plugs) - Niemidc, if you are around, could you please tell us if the charger is world voltage capeable?

Many Thanks,

Boricle.


----------



## k1_

Since it looks like I'll be getting a Stenlight via the GB in the near future, I've been thinking about how I want to mount it. I'm not a caver, and most of the time I'll be using it I won't be wearing a helmet. There have been a number of posts about how to connect the S7 to a headband or to your bike, and I figured I'd share a couple ideas I've had. Hopefully I'll be trying them all out in the near future...

For the bike mount, I'm thinking it might work well to buy this clip from batteryspace and then either bolt on a standard flat lamp bracket (part #16-9807 in the IMO catalog) or glue on one of the Speleo Technics "Rockfarer" brackets (part #16-9804 at IMO). For others like me who have trouble finding stuff in the IMO catalog, go to the Helmets page and scroll to the bottom. Not including shipping, this appears to be an adequate blade-compatible bike mount for about $10.

For the headmount, I already have a good headband that came with the Night Sun Lithium SunSport (which is a nice little lamp, although it's crying out for a hotwire kit). If you look at their product page, you can see the headband is a 3" strip of neoprene with hook and loop patches sewn on. Works pretty well, actually, and would probably be quite easy to make.

To attach the headlamp, I was thinking about either gluing one of the Speleo Technics blade mounts to a sturdy chunk of something (Delrin?) backed with your favorite velcro product, or maybe using a nylon lash tab from backpacking. Not sure about that one yet.

Hopefully my ideas will spark some fresh thinking in other folks minds, and we can get some really good stuff going. I'm looking forward to the Stennie.

k1


----------



## benh

I'm pretty freaking excited about the StenLight myself. I'm planning to put together some kind of handlebar mount for mine as well. Probably take a small hunk of steel or aluminum stock and make a replacement for the existing blade mount and tie that into a Cateye QR bracket. Not sure, as I'm more of a hands-on guy, so I won't really know what I'll do until I get the light.

I'm also pretty happy that I can simply get a higher capacity li-ion battery pack, such as this one here: 

http://www.batteryspace.com/index.asp?PageAction=VIEWPROD&ProdID=1257

and get 6 - 10 hours of runtime on turbo.


----------



## PeLu

I've used the Stenlight now on a few trips on our expedition and borrowed it to other people for the other trips. 
Even with the 30° optics the beam is too narrow for me and I prefer the Melzer Radon (personal preference). 
It seemed to be impossible (for a normal trip length)to run the light down until the overdischarge protection jumps in, the light just dims down when the cells get empty. 
The charger works fine at 230V 50Hz, but discharges the battery when mains power is off, this is a real big disadvantage, so I will look for another charger. 

I also made an emergency battery our of 3 CR123 cells (soldered together) and put them into a piece of bicycle inner tube, the same I made with a 9V block battery. I needed neither of them but lost the first one .-)

I changed the light to the much smaller BEC connectors which worked flawless the whole time. For a very wet trip which involved putting the head underwater we greases the conector and sealed it with insulation tape, which worked fine for a single trip, no signs of corrosion due to water coming in. 

The good thing is that the light is short and a little bit to the sides, so that it can light the survey instruments very well. So I didn't need any additional light for that purpose.


----------



## cave dave

I agree about the beam angle. I would like one LED right up close to the lens and only a shallow reflector to get max spread. I find myself constantly tilting it up and down so I can see my feet. on the lower settings.
I have taken to using a Tikka on Low at the same time as the S7 on Med. It kind of seems odd to have to use another light on at the same time just to see the ground in front of you. (very important in caving)

It is something awesome in big rooms, but for general practical caving I really don't think I would recommend this light as is. Especially considering the cost.


----------



## k1_

Hey cavers, question about blade mounts. Anybody have an idea where to buy the blade mounts themselves? Not the bracket that they hang on, but the actual blade (like the one mounted on the Stenlight).

I'm about to receive my new Stennie from the GB(woo hoo!), and in the process of figuring out how to connect it to my bike, my headlamp strap, etc., I've decided that I'd like to convert some other lights I own to blade mounts as well. That way I can interchange lights and mounts, since they'd all use the same connection system.

TIA
k1


----------



## cave dave

It totally depends on the other light in question. Petzl makes a blade mount conversion for some of their older lights.
Available somwhere on the IMO website
http://www.caves.org/imo/frames1.htm


----------



## PeLu

cave dave said:


> I agree about the beam angle. I would like one LED right up close to the lens and only a shallow reflector to get max spread.


Exactly. The 30° optics tell only half the truth. There is almost no sidespill to the sides, which makes it uncomfortable for me. 
But I have not tried to use a diffusor. 
I had a very good diffusion optic, which looked similar to the newer Petzl headlamp's diffusor, but it was too large to fit into the StenLight. 

For the blade mount: caving shops are a good source for any kind of lamp spare spare parts. And are usually helpful.


----------



## niemidc

Boricle said:


> Thanks Cy and JonSidneyB.
> 
> I suspect that the charger world voltage may be okay. The charger shown on the Stenlight site: http://www.stenlight.com/img/charger.jpg
> ...
> These indicate that those chargers are world voltage compatible (but don't have the Stenlight molex plugs) - Niemidc, if you are around, could you please tell us if the charger is world voltage capeable?
> 
> Many Thanks,
> 
> Boricle.



Yes, the chargers we sell work from 100-240V AC, 50-60 cycles.

As has been noted, if you hook them to a battery without being hooked to AC the charger light is green (regardless of the state of charge). It's a good idea to check the LED before attaching a battery and after removing it to avoid unpleasant surprises. And don't leave the battery connected indefinitely after it turns green.


----------



## niemidc

cave dave said:


> I agree about the beam angle. I would like one LED right up close to the lens and only a shallow reflector to get max spread. I find myself constantly tilting it up and down so I can see my feet. on the lower settings.
> I have taken to using a Tikka on Low at the same time as the S7 on Med. It kind of seems odd to have to use another light on at the same time just to see the ground in front of you. (very important in caving)
> 
> It is something awesome in big rooms, but for general practical caving I really don't think I would recommend this light as is. Especially considering the cost.



You may find that using a 25 degree lens instead of the 5 degree or 15 degree makes you happier. Other cavers who wanted a wider beam have gone this route. They are available at LED Suppy (www.ledsupply.com). We used dual 15 degree (+/- 15 degree, same as what PeLu calls 30 degree) lenses in our prototypes, and a majority of our field testers wanted more "throw" for long passages and vertical work, and they have been happier with the 5+15 combination. It evidently depends on how and where you cave...

It would be a challenge to move an LED right up against the front window with this design. You'd need to remove the LED, put in a copper or aluminum spacer, and attach long leads to bring power out there, and you'd need thermally conductive, electrically insulating double-stick tape. During development we tried some lights with LEDs right up against the window with no optics, and they were disappointing to say the least -- you get a little bit of light over almost 180 degrees but the light gets lost over such a large area, and you get no "throw" at all, so they were a real waste of power.


----------



## cave dave

niemidc,
If you haven't seen a Fenix L0P, you should check one out. I would consider this almost the perfect beam shape for at least one of the LEDs. Its amazing what they are doing with such a small reflector.

If you want to check one out I can send you mine on loan. Or I can bring it to spring VAR.


----------



## PeLu

niemidc said:


> (+/- 15 degree, same as what PeLu calls 30 degree)


Sorry for my inaccuracy, of course I used the 25° optics (even two of them). 
Independent from the illumination angle, the sidespill on higher angles is almost nothing. 
This is what I do not like (but others may not care). 



> During development we tried some lights with LEDs right up against the window with no optics, and they were disappointing to say the least -- you get a little bit of light over almost 180 degrees but the light gets lost over such a large area, and you get no "throw" at all, so they were a real waste of power.


This is exactly how my Melzer Radon behaves and I prefer it's light distribution, lets say 80% of the time, for my usual caving. 
Maybe there is an easier solution with some optics combined with Scotch tape or so. At least it is easy to try.

But, as we all know, you cannot please everybody.


----------



## cave dave

S7 Action shot! :thumbsup:

I really don't remember smiling during this part:


----------



## NewBie

I was looking over the specification page and saw a few issues I was curious about...

http://www.stenlight.com/fact-sheet.htm

TURBO- no limiting 7 watts 140 Lumens

TURBO mode is typically limited to 4-5W for long-term use due to thermal limiting. 

Okay, so we take 3.5W to each LED, say T bins were used, so we have T 67.2 to 87.4 lumens with a typical number being about 77.3 lumens.

We take the 7 Watts and divide by two and arrive at 3.5 Watts per LED.

The major issue at this point is 77.3 lumens which is what the T bin does at 25C die temperature (junction).

Now since Stenlight says they put 3.5 Watts into each, we need to add another 1/2 W or so of lumens, since the T bin 77.3 lumens is based off of 3W. This brings us to 90.183 lumens.

Now, we have to derate the Lumens due to temperature of the LED die (junction temp). 3.5W * 13 C/W works out to 45.5C junction to slug temperature rise. Then there is the rise from junction to case. In this application, there is a pretty good chance the body of the light reaches 40C or more (probably more- but I'm going to use a highly conservative 40C):

The unit will become hot if used in TURBO mode for more than a few minutes. The temperature is regulated to prevent damage to LEDs and to prevent burns, but the lamp may be uncomfortable to hold, especially after an hour or more of TURBO operation.

So far, we have a 40C case temp, and the junction to die rise of and addtional 45.5C.

Then there is the rise in temperature due to the thermal resistance of the case itself, 10C is a good typical number for a very robust thermal path (including slug to case thermal resistance with silver thermal epoxy).

So, we add up the numbers, and we get 40C + 45.5C + 10C, to arrive at 95.5C die temperature (due to my conservative case temp number, it is probably quite a bit higher than this, but I'll use the conservative stance).

Now, I take a look at the lumen derating chart for die temperature:




The chart is found here, http://www.lumileds.com/pdfs/DS45.PDF , on page 10.

As I see it on the chart, it looks like 76% of the lumen due to die temp losses (junction temp), or a 24% loss.

So we take the original number of 90.183 lumens and arrive at 68.539 lumens due to die temperature (junction temperature) losses.

Next there are the losses due to the optic. These typically range from 35% to 20%. Okay, lets use the 20% number.

68.539 lumens * 80% = 54.831 lumens

So we have two emitters..
54.831 * 2 = 109.662 lumens, on a double conservative losses estimation.

Did Stenlight ever have the unit tested in an integrating sphere? If so, were they for a steady state condition, or just measured within the first 100 millionths of a second? Or are the numbers on that page just a very rough guage?

Due to thermal limiting, I see the lumens drops to 70 lumens. Is this actual measured, or was it not de-rated like the other numbers?


----------



## NewBie

*Re: Cavers - The StenLight, Ultimate 2x3W LED Head*



jtice said:


> PeLu,
> 
> Hmmm good idea, that would make it more impact/crush proof.
> though I dont see why you really need that.
> But it would protect from deep gouges though.



The reason why you want things impact resistant, especially with Lithium Ion rechargable cells is that it it extremely dangerous to put small dents in them. Yes I too have seen Li-Ion cells with dents that didn't cause any issues, but I have also seen them vent violently with flame from a dent.

Not a good thing to have on one's person, especially around the head, while it vents with flame...

The PVC deal sounds like a really good idea.


Did Stenlight ever come up with a sealed connector to prevent water from getting into it?


.


----------



## PeLu

NewBie said:


> there is a pretty good chance the body of the light reaches 40C or more (probably more- but I'm going to use a highly conservative 40C):


Your caclulations are, as usual, quite well based, I just add my observation that the case did not become to hot too touch under normal caving circumstances. It seems that the humid air and the constant head movements cool down quite well. Even in hot caves (14°C).


NewBie said:


> The reason why you want things impact resistant, especially with Lithium Ion rechargable cells is that it it extremely dangerous to put small dents in them.


I'm well aware of this issue, as I wrote I'm looking for a PVC tube of appropriate diameter which I can deform.
Another solution is adding just a plate of strong plastic on the outside. In almost all cases the battery is on the outside of the helmet.
On the other hand, ther eis always some risk involved .-)


> Did Stenlight ever come up with a sealed connector to prevent water from getting into it?


I changed the connectors to much smaller ones (there is not more than 2A (when charging!) over them) and add a small diameter rubber tube (like a miniature bicycle inner tube). Further I keep my connectors inside the helmet. 
There are quite inexpensive AMP superseal connectors available (usual in car rally sport), we use them on other lights with good results. 
(I only have German links here, but could post the anyway).

Thanks for the valuable comments.


----------



## NewBie

I've used those AMP O-Ring sealed connectors before, they are pretty decent.


AMP SuperSeal connector drawing:
http://ecommas.tycoelectronics.com/...wing2821055pdfEnglishENG_CD_282105_5.pdf

You can buy them here:
http://www.mouser.com/index.cfm?han...e=AMP+Super+Seal+Connectors&pcodenumber=57279


----------



## PeLu

NewBie, I've just changed my Li-Ion batteries and protect them a little bit more. I take aluminium sheet metal and make a u-shaped protector around the battery. 
The 'front' side which touches the helmet is still 'unprotected', but I think it is fine.


----------



## noelex

AAA and Stenlight
I'm anxiously awaiting my Stenlight. It sounds like an awesome headlight and I'm really looking forward to getting it. Unfortunately I live in Australia so delivery will be a few days yet. In the meantime I am planning some battery packs for it.
In addition to a normal battery pack pack I would like to have a small battery pack for short trips. Basically I would be using the excellent efficiency off the Stenlight to achieve a short run time with a very small battery pack.
I would like a battery pack that he's as small as possible. The headlight would be used mostly on the low or medium setting. However I would still like to use of the brightest Turbo setting occasionally for a few minutes. This means the battery pack must be able to deliver an adequate current to the headlight.
I'm not entirely convinced about the safety off lithium ion batteries particularly as the headlight would be used with a headband and battery would be against my precious skull, so I was hoping to use 6 NiMh 900 mHr. Will have enough capacity and current delivery to work adequately ?
Any comments would be appreciated.
Thanks John


----------



## k1_

Noelex, if you ordered the Stenlight accessory kit, it comes with a connector for a standard 9v battery. That should give you all the features you desire, including the smallest-possible-battery setup.

k1


----------



## noelex

Thanks for the reply
A 9 V alkaline battery would certainly make the ultimate in a small head torch. The runtimes with this battery are very impressive and it shows the efficiency that has been achieved with the design. The web site quotes:
greater than 24 hours on low
six hours on medium
and one hour on high.
Given the high light output even on low and medium this is an excellent result, but it implies that the 9 V alkaline battery does not provide enough current to run the headlight on Turbo.
I would really like to be able to use tubo even for short periods of time, but my conclusions about the 9 V alkaline battery may be incorrect. Can anyone verify if the 9 V alkaline battery will run the Stenlight on turbo ?. I would also prefer the to run on rechargeable cells, but thanks for your reply your suggestion could be an excellent solution.
cheers John


----------



## PeLu

noelex said:


> Can anyone verify if the 9 V alkaline battery will run the Stenlight on turbo ?


No, it will not and I doubt the number for the high setting. But alkaline qualite is quite varying.
But actually, the standard pack is not so much larger than the 9V one. If you overcome your Li-Ion worries, this is the best solution. 
Another non rechargeable solution would be a holder for 3-4 CR123 cells.


----------



## cave dave

If you use a lithium 9v you can get a few seconds here and there with a brightness higer than High.
A 3x123 pack would be able to run turbo no problem.


----------



## cy

an expensive but light option is to use 6x AA lithium cells in std pack.


----------



## noelex

Thanks for the replies
I am still keen on rechargable AAA NiMh. Any opinions if 6 cells would put out enough Amps to run the turbo setting. If not would 7 or 8 cells work.
Cheers John


----------



## SilverFox

Hello John,

Welcome to CPF.

AAA NiMh cells are capable of staying above 1.0 volts per cell under a 1.0 amp load. If you limit your use in turbo mode, 6 AAA should work fine.

Tom


----------



## JonSidneyB

The balance of the group buy stenlights will be here wednesday or thursday at the latest. I will then start selling them as a regular item.


----------



## noelex

Thanks Tom
That is just the information I have been looking for. In the mean time I have found some 7.2 V 1850MHr Li IOn bat at only $3 each at a local electronic shop. I have purchased all they have (3) It looks like one is dead but the other 2 look OK. I am charging them as I type to see what capacity they have left.
Cheers John


----------



## Archangel

Are there two or three colors of LED in the Stenlight charger? Mine looks green now, but it looked yellow earlier.


----------



## benh

Got my Stenlight today. I charged it up along with my Planet Bike Alias SC 15 watt incan bike light and went for a little night ride in the suburbs, A/Bing between both lights on their brightest settings.

First thing I noticed is that my Alias has much more spill than the Sten, and somewhat more throw. The throw anyway is to be expected, as the Alias is a 15 watt light.

Second thing I noticed is that the Alias beam is YELLOW. The Sten is a nice bright white.

Wondering if switching optics might do me some good. Thinking of switching one to a bit more diffuse pattern for spill and one to a tighter pattern for throw. Also think I'll ride with it for a while before making any changes.

Thoughts?

At any rate, I think I really like the Sten. It's smaller, lighter and has better overall runtime than the Alias.

Only thing I'm not sure about is the stability of the blade pivot. I can't tell if the light is gradually pointing downward due to road vibration or not. I kepy messing with the aim as I rode so it's hard to tell.


----------



## noelex

You are making me very jealous. Stll wating for mine. Shipment to Australia is taking ages. :scowl:
Cheers John


----------



## PeLu

Archangel said:


> Are there two or three colors of LED in the Stenlight charger? Mine looks green now, but it looked yellow earlier.



Actually two, but when it changes it might look yellowish.

The blade mount could be made 'stiffer'. Just fasten the bolt.

And yes, it has less spill. This is my main critic on it.


----------



## JonSidneyB

I will be adding stenlights to the store on wednesday night.


----------



## Archangel

According to flashlightreviews.com, yellow is "mostly charged" (~.5hr away). (smirk) Boy do i love answering my own questions.


Archangel said:


> Are there two or three colors of LED in the Stenlight charger? Mine looks green now, but it looked yellow earlier.


----------



## wasBlinded

I posted a little mini-review, concentrating on the current draw characteristics of the Stenlight:

http://candlepowerforums.com/vb/showthread.php?p=1370491#post1370491

Very happy with it. Should be able to blood it in its first cave this Saturday!


----------



## cy

really looking forward to seeing feedback..


----------



## noelex

I received my stenlight. Yeah !!

It arrived on the 18th but I have been away for a couple of weeks so I've only just received it.

My initial impressions I that it's beautifully made, very bright and tiny.

I spent most of today making a headband out of elastic and 3 mm thick aluminium. I have removed the standard hard hat clip and attached the light by the hinge. This has the advantage of securing the Stenlight in a very positive fashion , it also slightly reduces the size and weight. I have not permanently changed anything and it is possible to reattach the clip if needed.

 I was very impressed with the hinge mechanism. With many head torches you get a simple self tapping screw . The stenlight it is more like a drag on an expensive fishing reel with three or four washers of various materials together with an aluminium spacer and a stainless steel bolt.

I made a battery pack with 6 small AAA cells I glued them into this to follow the contour of my head and the result is very comfortable. Even with this very small battery pack I should still get reasonable runtimes due to to the great efficiency off the Stenlight. The battery pack is rated at 900 mAHr, but the first discharge gave a capacity off 780 mAHr . The batteries are only cheap Chinese cells so I was reasonably happy with this result. The capacity often improves with the first few charges anyway. In theory 780mAhrs gives me run times of:



Turbo 0.78 hours

High 3 hours

Medium 9 hours

Low 55hours !!!!!!!



In practice the runtime on Turbo will be lower than these figures would suggest, as the small AAA struggle to provide sufficient current, but the light is very bright and I think I will use it most of the time on medium and low. The battery pack is held in place with some elastic and it is surprisingly secure. Different size battery packs all seem to fit reasonably well. The stenlight will run on a large range of voltages so it's easy to make up different battery packs.

I felt I would have to make a couple of headbands to get the results right, but I'm reasonably happy with my first prototype. It's very stable and comfortable.



Many thanks to my gorgeous wife who did all the sewing. (It's harder than it looks.) She even made a small pocket so I can carry a spare 9 V battery for emergency use.

I have some photos but I cannot add attachments.

Cheers John



PHP:


----------



## dbedit

I joined the ranks! and ordered one, cant wait to give it a shake down. I expect this thing will get serious workouts between caving, mtn bike, and camping. I was looking for a good headlamp, but see what happens when a Flashaholic goes looking......wallet gets more empty.


----------



## JonSidneyB

dbedit told me about a great idea for the stenlight.

build a battery tube with a spade mount on the end, so when it is not being used on a helmet, bike, or headstrap, it can be a flashlight. Hmmm

I will see if I can get this done.


----------



## jtice

BAH !!!!! I demand you guys stop reading my mind !!!!! 

That is going to be my next Sten mod, if I can ever get around to it.
My Tripod Sten has been working well 







~John


----------



## JonSidneyB

Sorry Jtice, That parts kit I sent you had a mind reading device in it.


----------



## cy

here's the config I used carrying stenlight at shotshow. 

twofish block in action again!!!


----------



## vtunderground

So wait... how are you _supposed_ to attach the battery to your helmet? Velcro?


----------



## JonSidneyB

It uses a spade mount.

Denise and I just simply attached a spade holder on the helmets. It is probably the most secure way to mount on a helmet.


----------



## cy

yes, you can use some industrial strength velcro that's available or if helmet has slots, use a two fishblock to hold batt pack.



vtunderground said:


> So wait... how are you _supposed_ to attach the battery to your helmet? Velcro?


----------



## jtice

I have an elastic strap holding my battery pack on my helmet.


----------



## NewBie

Has anyone came up with other techniques to protect the StenLight battery pack, beyond the PVC pipe trick one guy used?

How about any alternate sealed connectors?


----------



## bwaites

I took my Stenlight on a camping trip last night, wearing the barely arrived headstrap available from JSBurleys.

I wore the light for the better part of 6 hours and could NOT be Happier!!!

It worked GREAT. I still haven't killed the pack, using it mostly on medium until I went to bed, and then on low to read for a couple hours.

This light will take the place of virtually every one of my small LED's!!

It did everything I could ask of it. 

I am super-satisfied!!! It would be the perfect light if it threw an incandescent color instead of LED white.

Bill


----------



## wasBlinded

I just got back from a caving trip with my Stenlight, which was mounted to a Petzl Ecrin Roc helmet with a blade mount adapter. The day started off inauspiciously. When I opened my pack at the cave to pull out the helmet, the Stenlight was on the medium setting. It couldn't have been on more than a few hours, so I wasn't too worried about having run down the Li-ion pack significantly, but it does point out the need to disconnect the cell from the light to prevent inadvertent activation when traveling.

The light/battery pack balances well on the helmet and is relatively light - particularly compared to other helmets festooned with multiple lights in an attempt to get high output and redundancy.

Trying to get more of a flood out of the light, I put a layer of Write-Rite over the optics. It doesn't really spread the beam much, but it almost totally eliminates all of the artifacts inherent to optics. I don't want to imply that the Stenlight is a spot beam, because it isn't - especially with the Write-Rite. On medium (the most often used level) it is quite comparable to the beam thrown by the Petzl Duo LED (cluster of 14 5mm LEDs) which many cavers in this area use, but with the big advantage of whiter light with no blue center and much higher available output. I only occasionally switched to High or Turbo to light up bigger rooms. The tilt feature is great. I was able to angle the head up to properly light the way ahead on stomach crawls, and angle it down for task lighting. As a bonus, it will point almost straight up, which was handy when we spent about 30 minutes sitting in the cave talking. That gave a nice indirect light reflecting off the walls and ceilings above that didn't blind any of the other cavers. No other headlights in this group were able to aim high like that.

In summary, this light worked flawlessly and did everything I asked of it. We were only in cave for a total of about 5 hours, so the Li-ion pack wasn't close to being used up. Even if it had been, I had the 9v adapter & battery, and a homemade CR123x3 pack ready for backup. This gave great peace of mind. The light generated a lot of interest from the other cavers, and several times I was asked to go to Turbo mode to light up a larger room for everyone.

FWIW, my other backup lights were a Pelican 2630 Lux1 headlight in the pack, and a Fenix L2P/CR2 tube on a neck lanyard, but only the latter came into brief use to peer into a very small hole in a wall.


----------



## JonSidneyB

I thought this would be an interesting picture to run exposed AAs submerged in water. The first picture is before the connectors are pushed together but everything is under water.




I pluged and unpluged the connectors while they were submerged.




A light can run from an exposed battery pack while submerged.


----------



## Archangel

Party bonus!


----------



## bwaites

I had heard this was possible, but still haven't figured out why it doesn't cause a short!

In thinking about it, the wire springs are much more conductive than water is, electricity seeks the easiest path, so ?

Any EE's chime in!!

Bill


----------



## jtice

Yes bwaits,

Its all about the Path of Least resistance.
Thats why a car keeps the radio, headlights, and power windows running for alittle while if it is driven into a lake.

It should be noted,
This demonstration was to show that the Stenlight will operate totally submerged, in case of emergancy etc.

It is NOT recommended to do this.
It can lead to corrosion of the contacts, and create resistance in the system.

~John


----------



## JonSidneyB

sometime in the name of science, I will do some tests. I will do a runtime test in clear water, then creek water. I am thinking about seeing what will happen is salt water. If I do the salt water test, how much salt do I use per gallon of water to be a fair test.


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## bwaites

Ocean water is approx 3.5% salt or 35 grams of salt to every liter of water.

Thats approx. 1.234 ounces or since salt weighs .66 ounces per tablespoon, almost 2 tablespoons in a liter of water.

Since a gallon is equal to 3.79 liters, then use 4.676 ounces or 7.08 tablespoons in a gallon. (For me, 7 tablespoons is close enough!)

Bill


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## JonSidneyB

I just got off the Phone with SilverFox, He gave me the confidence to go ahead and try this.

I will go 8 tablespoons since seawater is slightly less than that.

I am thinking of using 8 gallons of water. Maybe I can have a more accurate measurement. how many tablespoons are in a cup or something. It would be nice to be able to measure out the salt in one nice batch.


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## vtunderground

Two more questions (couldn't find the answers on Stenlight's website):

Is the Lithium-Ion battery pack waterproof?

and,

Does the headlamp body have type II or type III anodizing?

I'm intrigued by the Stenlight, but pretty apprehensive. I can't exactly afford to replace a $300+ headlamp if it gets destroyed or damaged (or just quits working), so I'd want to know that this thing is going to last forever.


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## JonSidneyB

It is type 3 anno,

The batteries that come with the stenlight have something called a 3M dual lock fastner for helmets that is very secure.

I am going to go drop a stenlight li battery pack into the fish tank with a light right now. the stenlight battery packs are rubberized and I do not think they will leak at all but I will find out right now.


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## JonSidneyB

No bubbles from the battery pack at all...and it is running underwater right now. 

On durability. One has been dropped from 35 feet onto concrete then was swung by the power cord taking chunks out of concrete, the selector switch was bent but works fine after straightening out.

When I have the time, we are going to make a movie of a Sten getting abused and still function.

These lights can take it.


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## NewBie

JonSidneyB said:


> No bubbles from the battery pack at all...and it is running underwater right now.
> 
> On durability. One has been dropped from 35 feet onto concrete then was swung by the power cord taking chunks out of concrete, the selector switch was bent but works fine after straightening out.
> 
> When I have the time, we are going to make a movie of a Sten getting abused and still function.
> 
> These lights can take it.




Hi Jon.

Are you saying you took chunks out of the concrete with the battery pack or the aluminum head portion?


Some of the mine/cave water around here is actually acidic and in other areas alkaline, you might try running in a vat of that...


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## JonSidneyB

The head portion


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## NewBie

This is what I was referring to, as far as non-pure water and unsealed connectors the other day.

I have some mine water I collected while rockhounding, that I have actually been letting sit for many months now, watching crystals grow out of it as it evaporates. I'd collected it with my water bottle, as I'd noticed the crystals growning on the edges, and wondered if it was salt, calcium, or what...

I stirred up the mine water a bit, then I poured some of the water into a fresh jar, and added about the amount of tap water needed to bring it roughly back to the concentration it was. I also took a chunk of the stuff that grew on the side of the old jar, and tossed it in the bottom.

I then took 2 Li-Ion cells and hooked them to the Molex connector.

Unfortunately the water is very murky, and things are hard to see.





.


A close-up of what is going on:





.


After fifteen minutes, I pulled it out and took a picture of the contacts:





You can see the plating is gone from one contact exposing the copper beryllium or phosphor bronze base metal, the other contact has a black coating, and the other two contacts without power applied are normal looking.

Hopefully this clears things up.

IMHO, if the unsealed connector gets water in it, it would be a really great idea to take it apart and blow it out on both ends. 

Another thing folks could try is wrapping the connector tightly from the cable, over the connectors, and back over the cable, tightly with one of the electrical tapes that has stretch to it, keeping it tight at all times, and back wrapping it at one end.

Something else a person can use (to help-not fix), is the silicone grease they use with Marine battery terminals, to prevent corrosion (btw, it works great on car battery posts too...)


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## JonSidneyB

I don't recomend for normal use the things I am going to do to this light. I actually think a caving light should have the battery up and out of the way. In the even that this light does get dunked, I think the tests will show that it can take it. If the light ever does get dunked with lots of uglies in the water, clean it up when you get the chance. The litium pack is rubber armored but I am going to see if I can get an armored case to go around it made unless you guys know of a case that already exists for that purpose.


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## SilverFox

Hello Newbie,

What kind of run time did you get until the bubbling stopped?  

Tom


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## cy

a super cool option would be to make a CNC aluminum case that holds 2x R123 li-ion cells. simply use protected R123 to avoid protection issues. 

weight reduction for headband use would be pretty coool, with bash protection too. 

come to think of it, the $1 match case may work with a little modding.


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## jtice

I have been thinking about making a wired cap, to use with one of my 2x123 bodies,
and using that for a super light pack for headlamp use.
Bare in mind, you will need a minimum voltage to fire up the Sten,
2xR123 would just do it I think.

~John


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## wasBlinded

Using a 2xR123 pack you would need to cut the expected runtimes by 75% compared to the 18650 pack, but for casual use I think that would be fine. It should easily give 2 hours on High and 8 hours on Medium.


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## NewBie

Any idea how it would hang in there on Turbo with 2 r123?


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## PeLu

cy said:


> a super cool option would be to make a CNC aluminum case that holds 2x R123 li-ion cells. simply use protected R123 to avoid protection issues.


As NewBie mentioned, the two R123 cells will not be enough for the Turbo mode and further you pay double penalty for the protection.
The Stenlight battery pack has a quite good protection electronic (altough no balancing) and it is always better to let the work done by one circuit instead of two independant ones.
I'm quite shure, the drop will be more than 75%, anyway. 
The use 18650 cells are about perfect. Very good specific engery, load capability very well suited to the needs and easily available (=economic).

I've made now several batteries, most with 2 cells, but also some with 4 cells. I use a slightly better protection electronic than the original, but differences are not that dramatic (no balancing either, but an external contact for it to be done by an external circuit). 
As I also use very good cells, unbalancing has not been an issue now.

As I wrote, I changed to quite small BEC connectors (which have an incredibly low resistance too) and we had a few cases where cavers had to go through a duck (that sometimes means that you have to put yourself compeltely under water, so the light is compeltely submerged, only for a moment, but it will stay wet).

We did, as NewBie mentioned, I greased the contacts with petroleum jelly (the only grease we had at hand) und I wrapped it with insulation tape. This worked very well, but karst cave water is usually not very conductive (which slows things down but does not prevent them). 

With greased contacts you have to be very careful when changing batteries in a cave. The grease attracts mud magically .-)

And, BTW, I've seen so many corroded contacs in my caving career I cannot tell.
Always beware that the corrosion is independet if the light is switched on or off. As long as there is voltage across the contacts it will corrode. 
The higher the voltage, the worse.

For protecting the cells in my battery packs I changed to 'half shells' only on the outer part, the inside (towards the helmet) is only protected like the original StenLight battery pack. This saves weight and the need for a perfectly fitting tube size. 
My battery packs (o.k. the latter ones) are fully waterproof and I may change to waterproof connectors (not decided yet).

The 'attach a helmet mount to the end of a battery tube' has been already made long time ago (I think I've seen it in the 70ies or 80ies) . A caver used to use D-cells in a quite long tube (4 or 5 of them) and a miner's light headpiece. So it was the logical step to make such an helmet mount (or just the slot) on one end of the tube for non-caving use.


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## noelex

Can anyone give me details (such as model number and where they can be ordered) of the connectors used in the Stenlight ?
Thanks John


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## wasBlinded

PeLu said:


> As NewBie mentioned, the two R123 cells will not be enough for the Turbo mode and further you pay double penalty for the protection.
> The Stenlight battery pack has a quite good protection electronic (altough no balancing) and it is always better to let the work done by one circuit instead of two independant ones.
> I'm quite shure, the drop will be more than 75%, anyway.


 
A typical R123 has a capacity of about 600 mAh, compared to an 18650 of 2400 mAh - i.e. it has 75% less capacity than an 18650 and should give about 25% of the runtime. I feel pretty confident about that, so will stand by my previous statement. The 2xR123 battery pack will run the Stenlight in full turbo mode for 20 minutes or so (my WAG), but the 900 mA draw of Turbo (when the light is not temperature limiting) is a pretty good strain on the R123 and not really recommended. The 270 mA draw on High is no strain at all for the R123 and should easily give 2 hours of runtime.


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## PeLu

wasBlinded said:


> A typical R123 has a capacity of about 600 mAh, compared to an 18650 of 2400 mAh - i.e. it has 75% less capacity than an 18650 and should give about 25% of the runtime.


Capacity drops at higher loads and the protection circuits have higher losses (as they are two and desigend for lower loads). Because the resulting voltage is lower, the switching circuit will draw even more current (probably the first part of the dischrage) or the light will dim down. Anyway, the gained space and weight is not too much compared with the standard pack, so it is IMHO not worth trying it at all. Together with more hazzle charging it.

Connectors: The inavailability (here!) was one of the reasons we changed the connectors. 
People wanted either a waterproof connector or one small enough to fit it inside the helmet (of course, both features together would have been perfect, but not realistic). We decided for the latter.
Further, tehre is at least one reported problem with the stock connector.


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## cy

need to clarify.... when I posted comment about using 2x R123's. it was intended for headstrap use to reduce weight. 

naturally runtime would go down. agree that using stock 2x 18650 pack is the best for overall performance. surely one of us will figure out an EZ clam shell to protect 18650 pack. 

what sealed connectors should we be looking at?


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## benh

I'm thinking about a 4x18650 pack for increased runtime. Batteryspace had a few likely prebuilt packs out there.

I think the stock pack will fit in an Otterbox 1000.


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## wasBlinded

PeLu said:


> Capacity drops at higher loads and the protection circuits have higher losses (as they are two and desigend for lower loads). Because the resulting voltage is lower, the switching circuit will draw even more current (probably the first part of the dischrage) or the light will dim down. Anyway, the gained space and weight is not too much compared with the standard pack, so it is IMHO not worth trying it at all. Together with more hazzle charging it.


 
This might be significant in Turbo at the 900 mA draw, but on High, at 270 mA, these effects will be negligible. Whether it is worth doing for the weight savings was not the question.


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## JonSidneyB

I need to get around to trying the 9volt on a Sten... I have yet to do that.


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## niemidc

NewBie said:


> This is what I was referring to, as far as non-pure water and unsealed connectors the other day.
> ...
> Another thing folks could try is wrapping the connector tightly from the cable, over the connectors, and back over the cable, tightly with one of the electrical tapes that has stretch to it, keeping it tight at all times, and back wrapping it at one end.
> 
> Something else a person can use (to help-not fix), is the silicone grease they use with Marine battery terminals, to prevent corrosion (btw, it works great on car battery posts too...)



A couple of comments on this test -- we've done tests too. The connector fares a lot better when both sides are plugged in as this decreases the current through the water significantly, and better yet if you use dielectric grease on the contacts of one or both sides. The dielectric grease has a larger effect than, say, moving to gold-plated contacts. The connector in the picture looks like the larger (.093" contact) 4-pin molex with just 2 pins in it. Also, we use the gender shown on the LAMP side, as if you use that polarity on the battery side it can be easily shorted by a small metal object (and also worsens corrosion if it is exposed to water).

There are some types of water found in caves that are exceptionally corrosive and penetrating. On one trip to Warm River cave (Virginia) we had a fantastic number of equipment failures, including of a watch that I'd worn underwater for years. This was in the pre-StenLight days...


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## niemidc

benh said:


> Only thing I'm not sure about is the stability of the blade pivot. I can't tell if the light is gradually pointing downward due to road vibration or not. I kepy messing with the aim as I rode so it's hard to tell.



The swivel can be tightened with a crescent wrench (or a 5.5mm hex socket if you have one). Don't tighten it more than a tiny bit without checking to see the effects, it doesn't take much to make it much tighter.


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## JohnnyM

Hi All,

been following the Sten thread, very interesting, especially all the mods, battery packs and helmet mounts etc. Couple of things occurred to me. 

First, doesn't anyone make a neat, slim, waterproof connector for cables? Maybe something designed for a marine environment, which is extremely harsh on metal contacts, live or not. The nearest I've seen came with a Silva L1 headlamp, a brilliant little lightweight 3W Luxeon model, with the alternative of headband-mounted battery packs (2 packs, each with 2AA, to spread the load for night-running/orienteering) or a remote pack with a longer cable (4 x C cell for long life). The system was not intended to be waterproof, but the connector was excellent (circular in section, diameter of about 7 - 8mm), and to switch between the different battery options took about 30 seconds - just unplug the short cable and plug in the long one. I don't expect you'll have seen one, as Silva are imported (I believe) in the US by Brunton Industries, who don't seem to want to sell anything or make money ;-). I much prefer a (bigger) battery pack on a waist belt. On your head/helmet, it is vulnerable and uncomfortably heavy.

Second, Sten seem to be a bit slow with the headband option, so could I suggest (afraid I don't have the facilities at the moment to show/demonstrate) making an aluminium plate on the same pattern as that supplied with the Prolite strap system? Get a plate, cut two parallel slots, push centre section out slightly, add end and top slots for straps, round off all sharp edges, glue foam rubber backing, take the straps from a Prolite or Petzl and attach. Or cannibalise an old Petzl Zoom mount and go from there (simple, light, tough plastic, three straps, all still replaceable)?

Oh, one other thing. Re. bicycle lighting: if you ride offroad at night, it's dead useful to have a good headlamp as well as a bar-mounted system. On singletrack, the lights on the bars don't point exactly where you need them to go!

Take care out there,

JohnnyM.


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## cy

welcome to cpf Johnnym...

highly recommend jumping in and getting a stenlight. personally don't have any problems with clipping in stenlight to prolite strap. straps could be a little wider. 

you'll find stock 2x 18650 pack weight not very objectionable at all. or use longer cable and mount on your waist. another option is to use 9V cell in headlamp mode. this would reduce mass and runtime. 

I've never done a 9V runtime test. would someone post the runtime for 9V?


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## paulr

Here's some sealed connectors, but they are expensive and look kind of big:

http://ecatalog.westmarine.com/0541.asp?LinkBackProdId=165104


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## ianb

Has anybody tried the reflectored version with the new Seoul P4 LED's?, 
they should increase the output considerably and with a different regulator(lower mA levels) should give much longer runs on the standard battery.
I have wanted an S7 for some time, I have been waiting for the reflectored version to be official and think this would make an excellent upgrade.

Ian


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## Lurveleven

The Stenlight is already too bright for most use and has awsome runtime, but for turbo mode brighter is always better so I would have loved to have it with P4 LEDs, even if it was just to impress my friends 
However, so far I have mostly used it on medium and low and would actually have liked the low to be lower.

Sigbjoern


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## Mark620

PeLu said:


> And, BTW, I've seen so many corroded contacs in my caving career I cannot tell.
> Always beware that the corrosion is independet if the light is switched on or off. As long as there is voltage across the contacts it will corrode.
> The higher the voltage, the worse.




I have repaired caving lights(replaced wires) because the wires were corroded end to end...(from battery pack to bulb)


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## slvoid

A little expensive, but waterproof to 3-6'.
http://store.jbn-duraline.com/categ...ted-polarized-plugs-connectors-and-receptacle


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## wasBlinded

ianb said:


> Has anybody tried the reflectored version with the new Seoul P4 LED's?,
> they should increase the output considerably and with a different regulator(lower mA levels) should give much longer runs on the standard battery.
> I have wanted an S7 for some time, I have been waiting for the reflectored version to be official and think this would make an excellent upgrade.
> 
> Ian



I replaced the optics in my Stenlight with textured reflectors. The reflectors give a wider spill light than the optics. This helps with peripheral vision, but also is a little more annoying to fellow cavers. I wouldn't say that the overall output appears brighter, but the beam is smoother with fewer artifacts.

I've also replaced the Luxeon LEDs with SSC P4 Leds. Because the focus changes with the SSC, the extra light output goes into a larger but not more intense hotspot.


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## hadsnat

hi been lurking in the shadows for a while,decided to get myself a new light,where have most of you purchased your stenlights from? was it from pratt hobies or from somewhere else,has anybody had problems ordering from overseas through the pratt hobies store,i'm living in new zealand so makes things kind of hard.


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## cy

welcome to cpf hadsnat... you cannot go wrong with Stenlight. 

there's trusted folks on cpf that will forward lights to cpf're intn ... highly recommend insured shipping. cheap within US, but expensive overseas ($25). 

JSBurley was shipping intnl (out of stock), http://www.jsburlysflashlights.com/...=65.38.17.252&act=&aff=&pg=cat&ref=Head+Lamps

don't know if Stenlight will ship overseas direct, but it's worth a try..


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## PeLu

hadsnat said:


> where have most of you purchased your stenlights from?


Most US caving vendors will carry them. And there are some used ones available here in Europe form cavers who are upgrading their lights.


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## MajorJim

Well, I finally bit the bullet, so to speak. After looking for a long while, and making due with the older Petzl Duo 4 until the lens got so scratched up it was not very useful, I finally went with the Stenlight 7.

I got the headband option and the longer duration battery pack, as well as the alkaline adapters. 

I took a long hard look at the new Petzl Ultra comning out, and even if I could have gotten by the price tag, I just heard yesterday that they are pushing deliveries back again:



> *Hello! Our current expectations for Ultra availability is the Non-belt version will be available in December, and the belt version will be available in February 2009.*
> 
> *Sincerely,*
> *Petzl America*


 
For the price of a new Ultra, you can get the Stenlight 7 almost all of the extras. Plus, the Stenlight has proven itself very durable and reliable, something that is very important to me. 

Should have it in my hands and on my head next week. 

The new Surefire Saint was also tempting, but the delivery times at this point are somewhat uncertain. I can get the "dual battery option" with the Sten (and did), plus 2 3Watt lamps to the Surefire's one lamp. The 100 lumens rating on the Surefire is attractive, but what it's actual output will be remains to be seen.

Happy with my decision, although my wallet is lighter.


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