# Roar of the Pelican - Lithium Edition (done)



## KevinL (Oct 15, 2005)

For those unfamiliar with the ROP Project, you can get up to speed here.

The original ROP is this big fat thing built out of a 4D Mag re-sleeved to hold six SubC NIMH cells. As you all know, 4D Mags are not exactly the height of portability especially when you want to walk far on foot, so I wondered if there was a way to get a similar amount of power in a smaller light. 

Enter the 2C Maglite. 







Shown next to a Surefire M3, and U2. Some of us realize the 2C Mag and the Surefire M4 are similar sizes. Can I possibly modify the 2C Mag to deliver the same, or better output than the M4? 


The project calls for the use of the #3854 Pelican Big D SLA rechargeable bulb (PR base), metal reflectors and Borofloat glass. Power pack is 2 x 18650 unprotected lithium ion - you deanodize the tailcap to get enough room for the whole lot to go in.

Let's see some beamshots - ROP/LE on left, Surefire MN61 on right. The ROP/LE has a brighter corona (not so visible in beamshot), bigger and brighter spot, but the MN61 focuses the light into the beam better so it has less sidespill but a hotter spot. In person, the difference is quite visible. 






The "low output" (if it can even be called that) lamp for the ROP/LE, the 11W Pelican bulb that comes as part of the pack, will probably match the MN61's output with 350 output lumens. 75 minutes.

The high output bulb (shown above) 24W, delivers approx. 550-600 output lumens from the front end. 25 minutes.

Not bad for a 2C sized light that's easily portable and carry-able. 

You must be familiar with the use and handling of unprotected lithium ion cells if you want to use the high output bulb. Protected 18650s will run, but only with the low output bulb, however, as I said low is hardly even low!

At this time I *believe this may be the brightest 2C mod available.* Please correct me if I'm wrong. 

Feel free to ask any questions in this thread (don't PM, I might not have time to answer individual questions), so that others can chip in with their opinions as well.


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## SJACKAL (Oct 15, 2005)

Kevin, where can I get the parts? I got a Mag2C lying around idle. I will be getting the stippled reflectors once they are out and will get borofloats too. Where do I get the bulb and cells and charger? Are these R123 cells?

BTW my Mag2C is fully stripped of its anodising down to its bare aluminium. Any problems for that?


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## js (Oct 15, 2005)

Kevin,

BRAVO!

Nice!

As far as I know, this is indeed the brightest Mag2C mod available. Before this it was an 1160 2C, with 5 1/2SC NiCd's inside via a bored-out tailcap. But now, we have the ROP LE.

Congratulations.


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## Dukester (Oct 15, 2005)

Nice Photo's Kevin...


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## larryk (Oct 15, 2005)

I put together a 2C Maglite some time ago using the WA 1185 bulb and 3 unprotected 123's. This was only out of curiosity to see how it would work. I do not recommend using this set up because I am really pushing these cells hard, and li-ion can be dangerous. I built the light not as an every day light but as a novelty light to show to friends and co-workers how bright my lowly 2C Maglite is. I still occasionally use it, but again I stress that I do not recommend this set up for obvious reasons. Heres I link to the original post.
http://candlepowerforums.com/vb/showthread.php?t=79704


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## bwaites (Oct 15, 2005)

Larry, 

You are so far past the safe point with the those 123's that you LITERALLY have a bomb in your hands!

That is pushing the 123's at 5-6C! 

2C is considered the upper limits of safe, 3C is getting scary, 4C is "danger, Will Robinson, danger!!" territory. 5C is undeniably crazy!!

Bill


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## js (Oct 15, 2005)

bwaites said:


> Larry,
> 
> You are so far past the safe point with the those 123's that you LITERALLY have a bomb in your hands!
> 
> ...



Not only that, Bill, but I very much doubt--in fact I know for sure--that the R123's will be sagging under load to such an extent that the voltage applied to the 1185 will not be anywhere near 10.8 volts, and thus the lumens output will not be anywhere near 800 lumens. I would guess that the ROP LE with HOLA would be brighter.

But in any case, I don't mean to trash on anyones light or idea! However, 5C really is NOT a good idea with R123's.


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## larryk (Oct 15, 2005)

Jim and Bill, I understand your concerns, and I am not promoting this as a smart thing to do, and I will again recommend others not to try this. But as far as brightness goes it was the same as my Mag85 using 9 1650 high current nicad cells with fivemega's 9 cell holder and it was just as bright if not a little brighter, so I do not believe the voltage sag was all that great. I ran the light for 10 minutes straight and there was no fire or explosion. So I feel comfortable using it for 30 seconds or less. But that's just me, and I tend to live life a little on the edge. Larry.


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## KevinL (Oct 15, 2005)

Thanks guys, it's good to see this project come to fruition.

The ROP/LE proto just went out on its second field test today and I enjoyed it. While it is not exactly a throw monster, the fact that it reaches out just as far as both the Surefire SRTH and KT1 turboheads is impressive, that, and it provides this gigantic wash of light both in the beam and the sidespill. 

Longevity of the bulb does not seem to be an issue. This bulb has been used in my original ROP, clocked maybe ten hours, been flashed repeatedly (one of the field testers was strobing it), and it seems to be a really tough bulb. 

Bulb availability has always been a problem to us international users because again, all of us are crooks just waiting to rip off every honest US merchant at every available opportunity. Good luck to anybody wanting one. 

A completely deanodized Mag should not pose any problems, as long as the inside of the tailcap is deanodized as well because you need that extra space for the 18650s.

Safety issues - the low output lamp pulls 1.8 amps. With 2400mAH cells, this is 0.75C. The high output lamp pulls 4 amps, or 1.6C from 2400mAH cells. There is a reason why I insist on 18650s, and the highest capacity/highest quality A2 grade LG Chemical cells that I can lay my hands on - they are the only cells whom I believe have the capability to withstand the punishment the bulb will dish out. 

Voltage sag is an extreme problem with lithium ions, I estimate that even with the best cells I can buy, the ROP/LE pulls voltage down from 8.4V fully charged all the way down to 6.4V. It's worse with small cells.


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## scudinc (Oct 15, 2005)

I had just been thinking about making one of these; nice to see that it works so well. Could you explain a bit further on how you did the negative contact?


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## js (Oct 15, 2005)

larryk said:


> Jim and Bill, I understand your concerns, and I am not promoting this as a smart thing to do, and I will again recommend others not to try this. But as far as brightness goes it was the same as my Mag85 using 9 1650 high current nicad cells with fivemega's 9 cell holder and it was just as bright if not a little brighter, so I do not believe the voltage sag was all that great. I ran the light for 10 minutes straight and there was no fire or explosion. So I feel comfortable using it for 30 seconds or less. But that's just me, and I tend to live life a little on the edge. Larry.



Larry,

Something odd must be going on here, then, because not even LG Chem 18650's can hold 3.6 volts against a 3C discharge. In fact, the 2400 mAh LG 18650's will only hold 3.1 volts per cell at 3C. So it is beyond belief that your R123's would do significantly better, and at 4 or 5 C no less!

So at 3.1 per cell, we get 9.3 volts, which is even less than the 9.6 rated voltage (or about 720 bulb-lumens).

Whereas--on the other hand--the CBP 1650's will hold better than 1.2 volts per cell even at 5 amps, yielding a full 10.8 volts or slightly higher delivered to the 1185 for about 1234 bulb lumens.

SO, either your battery holder has got resistance in it, or your switch/pedestal assy does, or you've got a bad cell. But something is wrong, because unless you have special black ops military R123's, there is no way that your 3xR123 1185 light should equal a properly functioning Mag85 on 9 CBP1650's.

I'm sorry if I sound like a jerk here. It just doesn't add up, that's all. Perhaps I am missing something?


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## juancho (Oct 15, 2005)

KevinL,
You said that protected 18650 (from AW ??)will run the LOLA bulb, but I can not make them do it!!??

The best I could run so far is regular and xenon Maglite bulbs for 5 cells and the Carley 612, also the PR 112 (but it didn't last)
Right now that the batteries are reading 3.9 volts I am using a 4 cells Maglite bulb (cheap and I have spares) but I burned two of them when I intented to do that when the batteries were at 4.2 volts.

So my question is, are your protected 18650 from AW or they are from another source and they have more amperage than AW's cells???

Juancho


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## Grox (Oct 15, 2005)

Correct me if I'm wrong, but wouldn't the saphion hi-current 18650s work in this application, albeit at the cost of runtime?


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## pcmike (Oct 16, 2005)

I keep seeing the C designation thrown around (e.g. 2C, 3C, 4C, 5C)... what is C representitive of? Thanks!


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## CLHC (Oct 16, 2005)

pcmike said:


> I keep seeing the C designation thrown around (e.g. 2C, 3C, 4C, 5C)... what is C representitive of? Thanks!


 
I believe they're referring to battery size such as: AAA, AA, C, and D size battery cells. . .Of course, I stand to be corrected!


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## KevinL (Oct 16, 2005)

juancho said:


> KevinL,
> You said that protected 18650 (from AW ??)will run the LOLA bulb, but I can not make them do it!!??
> 
> The best I could run so far is regular and xenon Maglite bulbs for 5 cells and the Carley 612, also the PR 112 (but it didn't last)
> ...



Ooops, hmm.. I stand corrected 

I have never used protected 18650s of any kind, ever, (except the kind in my laptop), I was basing my assumptions on AW's specifications that they would be able to be discharged up to a maximum of 1.5C. The Pelican LOLA only pulls 1.8-2 amps, which should be below this 1.5C maximum rate.

Oh well, I guess it's just another argument to use unprotected lithium ions..


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## pcmike (Oct 16, 2005)

CHC said:


> I believe they're referring to battery size such as: AAA, AA, C, and D size battery cells. . .Of course, I stand to be corrected!



I actually figured it out. C = maximum average recommended discharge [C]urrent and you can multiple the C rating x capacity to get maximum recommend discharge rate.

--
C Rating
LiPo cells are also commonly given a C or current rating. This is the maximum average recommended discharge current for the cell. For example, the Thunder Power 1900mAh packs have a 6C rating. To determine the maximum recommended discharge rate multiply the capacity times the C rating. 1900mAh x 6C = 11,400. So the maximum recommended discharge rate would be 11,400mA or 11.4 amps. If your application has a higher amp draw, remember that LiPo cells can be wired in parallel, and with 2 cells in parallel each cell sees half the total current. With 3 cells in parallel, each cell see one third the current.

By wiring packs in a combination of series to get the voltage and parallel to achieve the capacity and individual cell current to an acceptable level, LiPo cells can be used to power nearly every type and size of model. 
--
From: http://www.horizonhobby.com/Explore/Article.aspx?ArticleID=1274


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## CLHC (Oct 16, 2005)

pcmike said:


> I actually figured it out. C = maximum average recommended discharge [C]urrent. . .



See what I mean? I stood to be corrected. Thanks for the detailed information regarding Lithium Polymers and the (C) rating. I consider myself ignorant of electronics no matter how I broach the subject. Tried to learn that years ago in high school even though given the schematics of the wiring set up for a custom 55 Chevy Nomad. I was proud of myself when the project was finished until the dash fried! ! !

Doesn't mean I _*can't*_ learn—it just takes me longer than usual. . .


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## Grox (Oct 16, 2005)

The way I understand it...

C actually stands for the capacity of the cell.

So for a 1800mAh cell C=1.8A, for a 800mAh cell C=0.8A. Discharging a 1000mAh cell at 1C would be 1A; at 2C would be 2A and so on. The point of this is that some cells just don't stand up well to high discharge rates. So it would be safe to discharge a normal primary cr123 at say 1C but 4, 5, or 6C, as noted above, would be pushing the limits of safety. Too much draw on the cell is bad for it.

Depending on the cell chemistry, different discharge rates will be safe/unsafe for it. Eg. high current NiMh (used in the USL) are happy at 5 or 6C whereas some batteries eg. primary CR123 would be dangeously stressed.

Hope that helps.


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## SJACKAL (Oct 16, 2005)

Kevin I am much interested. I plan on doing one too once I get some free time.


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## Icebreak (Oct 17, 2005)

What pcmike and Grox said sounds right. Much of what we here about electricity and electronics is hearsay and even heresy.

C is a unit of relative current for batteries. For a particular battery, a current of 1C is a current in amperes numerically equal to the rated capacity of the battery in ampere hours. In other words, a 1C current will completely charge or discharge the battery in one hour. A 6C discharge empties the battery in 10 minutes if it is rated to handle it. 

I don’t believe any of this because I’ve never seen an ampere. I think they are bits of human chi that can be used to produce human light waves or an aura. They are no doubt drained from the factory workers and put into batteries for later use.

A coulomb is a made-up term to convince us that amperes are real and have a measurable charge.

C also is a value placed on any given flashlight aficionado. It dates back to Roman times and it is equal to 100 flashlights. I have 50 flashlights so I’m a ½C flashaholic. Craig, I believe, is an 8C flashaholic. 

Further, C supposedly refers to the set velocity of the speed of light. Also false. As we all know light changes speed. If it didn’t all of our optics woudn’t work. 

Photons are some more magic. Some say they are particles, some say they are waves. They are neither. They are star sparkles. Filaments and LED grids are made primarily from meteorites. When you introduce electricity to them the star sparkles come out. They are pretty and bright but not as fast as scientists say because kitty cats can catch them. Try it if you don’t believe me.

Then we have all that guff about candela. A standard was adopted that defined the candela as the intensity of 1/600 000 square meter of a "black body" (a perfect radiator of energy) at the temperature of freezing platinum (2042 K) and a pressure of 1 atmosphere. Have you ever heard of anything so ridiculous? That definition has also been discarded, and the candela is now defined to be the luminous intensity of a light source producing single-frequency light at a frequency of 540 terahertz (THz) with a power of 1/683 watt per steradian, or 18.3988 milliwatts over a complete sphere centered at the light source. Blah, blah, blah. A candela is the brightness of one standard sized Italian candle. How hard is that?

So what about all these experts? EEs or Electrical Engineers are _Sorcerers_. People that claim to understand electricity are _Magicians._ Don’t believe everything they say.

Magnetic flux density only exists in the movies so a tesla isn’t what the Sorcerers or Magicians tell you it is. A tesla is simply a large, very bright flashlight. Following the fact that magnetic flux density doesn’t exist, we can conclude that a weber is just a good grill and a Maxwell is that guy at the party that insists that he can cook the steaks the best. Maxwells should be appreciated because they give us time to kick back and relax.

A nanohenry is a small, tasty candy bar.

Ohm is the sound I make when I'm having a nice steak, eat a good candy bar or when I have a rare moment of understanding something about electricity.

My apologies for the off topic. I thought it important to clarify some of the terms we hear on CandlePowerForums.

--------------

- Jeff


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## KevinL (Oct 17, 2005)

SJACKAL said:


> Kevin I am much interested. I plan on doing one too once I get some free time.




You were right too, all those months ago when I was telling you that LED Mag mods were the newest, hottest thing on the block. 

LEDs be damned, at least until they can start pushing 800 bulb lumens  you won't catch me putting a LED in a Mag these days because the size to output ratio is simply not there. LEDs work better in small, pocketable lights. If I'm going to carry a big light, I want ALL the power I can get it!


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## KevinL (Oct 17, 2005)

Icebreak said:


> Photons are some more magic. Some say they are particles, some say they are waves. They are neither. They are star sparkles. Filaments and LED grids are made primarily from meteorites. When you introduce electricity to them the star sparkles come out. They are pretty and bright but not as fast as scientists say because kitty cats can catch them. Try it if you don’t believe me.




Clarke's Third Law:
Any sufficiently advanced technology is indistinguishable from
magic.

G's Third Law:
In spite of all evidence to the contrary, the entire universe
is composed of only two basic substances: magic and bullshit.

H's Dictum:
There is no magic ...


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## Lurveleven (Oct 17, 2005)

js said:


> I'm sorry if I sound like a jerk here. It just doesn't add up, that's all. Perhaps I am missing something?



I agree that it doesn't add up. I tested some R123, results posted here, and already at 2C the MPV was down to 3.4V which is less than what CBP 1650 delivers. I think the big problem is that people compare the brightness at the start of the run, and even at high drain you get high voltage at the beginning of the run, which can be deceiving since it will fast drop like a stone.

Sigbjoern


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## K5Guy (Oct 20, 2005)

Will AW's unprotected 18650 cells run the ROP mod safely and at peak performance?

Thanks


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## KevinL (Oct 26, 2005)

A few more words about the ROP/LE before I go on vacation -

The "low output" lamp may be a better match for the 2C. I just loaded mine, and it burns incredibly white. I have two ROPs now, one is a 4D, one is a LE. The low output lamp and the LE outperform the 4D (NiMH pack) with high output lamp, and the low-output/LE combo has a MUCH whiter CCT than even the Surefire MN16. Beam quality is remarkably Surefire-ish, even when side by side with a real Surefire. I estimate output lumens at around 400, which is very impressive. 400 output Lu for 75 minutes is definitely nothing to sneeze at. 

I suspect the better performance is in part due to the bulb's lower current demands, and as such, the lithium ions do not sag as much in voltage - so they perform better. 

I personally feel that the lithium edition runs best with the low output lamp for these reasons, while the 4D NiMH runs best with high output lamp. That's not to say you can't use the high output lamp in the LE (I used to run mine that way), just that you don't get the most bang for your buck.


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## WhiteHot (Oct 26, 2005)

So do you think that the LO Pelican bulb would run on AW's protected 18650's? That would be awesome. I am trying to build something I would feel comfortable giving to a non-flashaholic. I am using the CA1499 inow but would like something a bit brighter and more available.


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## gchand (Oct 26, 2005)

Kevin, 

Wow, how did you fit two 18650 cells into a 2-C MagLite?? I have 
modified a 2-D light to take the 18650's, but there wasn't much room for 
any kind of a spring in the tailcap (I eventually wound up using a 3/4" piece 
of .45 recoil spring). Are you running the tailcap directly against the back 
of the batteries?

WRT the bulb, in the above mentioned 2-D light I used a potted WA 1274, 
which worked out quite well, and was actually brighter than my "classic" 
Mag74 using FM's 6-cell NiMH battery holder w/CBP1650 cells. The WA site 
ratings on the 1274 are 550 lumens @ 7.2V and 950 lumens @ 8.4V, so it 
would seem similar in output to your 24W Pelican bulb, although the Pelican 
bulb would probably be easier to obtain thru "normal" flashlight suppliers. 
Upon further thought, you say your 24W Pelican bulb rating is lumens 
out the front end, whereas the WA ratings are bulb lumens, so the Pelican 
bulb would indeed seem to be significantly brighter!

Thank you for your informtive post, and I see a 18650 powered 2-C 
light in my future!

George


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## tch_popeye (Oct 27, 2005)

Neat thread.	

I've been struggling to decide whether to use 6xNiMH C cells or 4x18650 cells in my 6C mag. I've already ordered the Pelican bulbs from a local electronics shop.

Before anybody points out the error in my math, let me explain: I intend to run the protected 18650s as a 2S2P configuration, i.e. 2 cells in series, in parallel with another 2 cells in series. This would halve the current requirements from each 2-series (2S) stack. Based on KevinL's numbers, the 24W bulb pulls 4A (although 24W / 7.2V only equals 3.33 A?). When half of this overall drain is applied to each 2S stack, they should each see only 2A, which is well below the 1.5C maximum discharge rate on a 2200 mAh cell (1.5 * 2200mA = 3.3 A).

My only concern is Juancho's statement that his protected cells would not yield 0.75C for the lower 11W bulb. Has anybody figured out why this is the case? (maybe the cells are low capacity, e.g. less than 1200 mAh, which times 1.5C only barely equals the required 1.8 A)

-Trev


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## WhiteHot (Oct 27, 2005)

tch_popeye said:


> My only concern is Juancho's statement that his protected cells would not yield 0.75C for the lower 11W bulb. Has anybody figured out why this is the case? (maybe the cells are low capacity, e.g. less than 1200 mAh, which times 1.5C only barely equals the required 1.8 A)
> 
> -Trev



That is exactly why I (re) asked my question above. It seems like the protected 18650's should be able to do it. Has anyone besides Jauncho tried it? I have some cells coming from AW in the next few days. I just ordered some Pelican bulbs to try it so I should know in a few days.


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## bwaites (Oct 27, 2005)

Pila protected cells will light the lamp about every 10th time I push the button.

It's the startup current that is the problem, and the protective circuit won't let it happen consistently.

Thus the need for unprotected cells.

The 2S2P idea should work, but it is a hassle. That is a lot of length for the runtime.

Bill


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## tch_popeye (Oct 27, 2005)

bwaites said:


> The 2S2P idea should work, but it is a hassle. That is a lot of length for the runtime.
> 
> Bill



I hear you about the hassle, but I'd give my left, er... for a magmonster that didn't self-discharge so badly. I'm up for the challenge, I think.

By "lot of length", I assume you mean the form factor of the 6C light? You're right, of course - I can only get 4.5 18650 batteries into the same length stack as the 6 C. Perhaps with sneaky digging, I could get a 5th, but that isn't so easy to accommodate in a 7.2V nominal setup.

Better yet, I'd prefer to be able to cut the length down after getting the 18650s fit. Can anybody recommend a good way to rethread the tube, so that I can reattach the tail cap after such a hack job??

I'm really looking forward to a ROP/LE that'll spray 24W for over an hour!  Thanks for the leg work, KevinL.

-Trev


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## Lurveleven (Oct 28, 2005)

tch_popeye said:


> Based on KevinL's numbers, the 24W bulb pulls 4A (although 24W / 7.2V only equals 3.33 A?).



24W/6V=4A

At 7.2V the current will be 4.4A, that will be 2.2A on each of your 18650 stacks, which is too much for those protected cells. So your setup will not work (but if you use Pila168A instead it should work).
Btw, if you want a really bright Li-Ion driven light, then Fivemega has the following two alternatives available (that IMO is much better than your 6C idea):
Fivemega's 1300 Lumens M*g85 Powered by 9x150S Pila
2-1/2D M*g powered by 6x168S Pila

The last alternative should be able to run the Pelican bulbs as well, I will try tonight if it is able to fire up the 24W bulb.

Sigbjoern


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## KevinL (Oct 28, 2005)

Trev, you're welcome  

Glad to see others carrying the torch as well (literally and figuratively), and coming up with their own battery configurations. 4D, 2D, LE, etc. are the ones I have thought of, it's good to see new and fresh ideas. Someone else mentioned to me they built a variant on a different power pack; great! All it takes is a way to deliver at least 6V at 4A to the high output bulb.

My 4D with six SubC NiMh comes close to the 1 hour mark, maybe around 50 minutes, but is considerably heavier because of the batteries.

Earlier question about fitting 2x18650 in Mag2C - remove the spring and the contents of the tailcap, you will notice they fit with a little bit of wiggle room. You then need to strip the anodizing from the inside of the tailcap using sandpaper, lye, flux capacitor etc.  and put in something conductive, maybe a small spring, to take up the slack.


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## tch_popeye (Oct 28, 2005)

Lurveleven said:


> 24W/6V=4A
> 
> At 7.2V the current will be 4.4A, that will be 2.2A on each of your 18650 stacks, which is too much for those protected cells.
> 
> Sigbjoern



Ahhh, Sigbjoern. I read your post and immediately saw my error. I made the mistake of finding a *lower* current through a fixed resistance, due to a *higher* voltage. Silly, indeed.

In fact, the numbers seem to work out a little different from yours, also. Nominally, the 24W bulb is supposed to run on 6 V (lead acid version, right?). This makes the intended current draw 4 A. 6 V / 4 A = 1.5 ohm... this is the bulb resistance. Now, if we apply 7.2 V to a 1.5 ohm resistance, we should get 7.2 V / 1.5 ohm = 4.8 A. Please correct me if I've done something wrong.

The fancy news, is that this nominal 24W bulb will be putting out 7.2V * 4.8 A = 34.56 W!! We're approaching a respectable proportion of a single car headlamp, here. (mine are 55 W)

The thing I wonder is, why do you say that the 2200 mAh cells won't be able to source 2.2 A?? This is only 1 C, on a battery rated for up to 1.5 C continuous.

You're making me nervous... it's not too late for me to chicken out and get 6 x C NiMH - but then I'll have been littering a good thread with non-lithium detritus... 

-Trev


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## Mags (Oct 28, 2005)

No offense or anything, but too much tech talk for me... :dizzy: So on 2 Pila 150a or 2 168a the 24w bulb should work right?


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## Lurveleven (Oct 28, 2005)

tch_popeye said:


> Nominally, the 24W bulb is supposed to run on 6 V (lead acid version, right?).



That is correct.



tch_popeye said:


> This makes the intended current draw 4 A. 6 V / 4 A = 1.5 ohm... this is the bulb resistance. Now, if we apply 7.2 V to a 1.5 ohm resistance, we should get 7.2 V / 1.5 ohm = 4.8 A. Please correct me if I've done something wrong.



The problem with your calculations this time is that the resistance is not a constant, it increases with temperature. To calculate the re-rated current use the formula you find in this post.



tch_popeye said:


> The thing I wonder is, why do you say that the 2200 mAh cells won't be able to source 2.2 A?? This is only 1 C, on a battery rated for up to 1.5 C continuous.



It has nothing to do with what the Li-Ion cells manages, instead it has to do with how the protection circuit on the cell is built. That is why the Pila168A will work, but not the protected 18650 from AW.

Sigbjoern


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## bwaites (Oct 28, 2005)

Sig,

My 168A's won't work, at least they only work about every tenth or 15th push!!

Bill


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## WhiteHot (Oct 28, 2005)

KevinL said:


> Earlier question about fitting 2x18650 in Mag2C - remove the spring and the contents of the tailcap, you will notice they fit with a little bit of wiggle room. You then need to strip the anodizing from the inside of the tailcap using sandpaper, lye, flux capacitor etc.  and put in something conductive, maybe a small spring, to take up the slack.



I had to move my switch forward a bit to get protected 18650's to fit. The unprotected cells are shorter, right?


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## Lurveleven (Oct 28, 2005)

bwaites said:


> Sig,
> 
> My 168A's won't work, at least they only work about every tenth or 15th push!!
> 
> Bill



I refered to Trev's use in his parallel setup, were they should work. A single stack will not work, it is hardly able to handle the current from a WA1185 (often needs multiple clicks). Sorry for the confusion.

Sigbjoern


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## Lurveleven (Oct 28, 2005)

WhiteHot said:


> I had to move my switch forward a bit to get protected 18650's to fit. The unprotected cells are shorter, right?



The protected cells are ca. 2mm longer.

I measured the Mag 2C body to 131.5mm, which leaves 1.5mm slack for 2 unprotected cells, but with 2 protected cells you are 2.5mm short (3.5mm with Pila).

Sigbjoern


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## tch_popeye (Oct 31, 2005)

Lurveleven said:


> The problem with your calculations this time is that the resistance is not a constant, it increases with temperature.
> Sigbjoern



I hope that when I reach several hundred CPF posts, I'll be as smart as you, Sigbjoern. You've almost certainly save me some cash, here - thanks very much.

I'm off to learn a bit more about those Pila batteries...

-Trev


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## PlayboyJoeShmoe (Jan 7, 2006)

While it would be so freaking great to run a ROP on two Li-Ions, even at only 30-40 bucks for two batts and a charger may as well be hundreds of dollars. I haven't even been able to grab some ROP bulbs yet.

But when I do I'll just have to see what Energizer(Sanyo) 2100s and Rayovac 1800s think about it all.

It rather hoovers to be  so often....


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## leukos (Jan 7, 2006)

I sold my Mag85 a long time ago, got tired of charging 9 batteries every time. But the ROP LE looks a little more user friendly, I could see myself throwing one of these together pretty soon. My non-flashaholic friends get more of a kick out of Magmods than out of my SF's.


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## mattyg (Jan 7, 2006)

OK, I'll admit to my noobish status right here and get that out of the way. Not new to flashlights but new to modding them.

I have a 3D Mag & 2C Mag that have been sitting around since the late 80's. They are in great shape and I've really hardly used them. This morning I went out and got 4 C cells for the 3D and some PVC pipe for a sleeve shim. Drop in, works great.

I want to do the ROP/LE conversion on my 2c Mag. After perusing this post here's what I've surmised I need to do. Someone correct me if I'm wrong or have omitted a step. Also have a few Q's.

Buy: 
3854 Pelican bulb
metal reflectors and Borofloat glass (where do I purchase these and what size specifically?)
2 x 18650 unprotected lithium ion cells (How do you charge these?)

De-anodize the inside of the tailcap, remove old components and reassemble.


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## cmacclel (Jan 8, 2006)

I'm suprised no one has chimed in here

Your 2c *unprotected* lithium ROP is cool. I myself have a *unprotected* 2 cell LG2400 18650 Lithion Ion powered WA1111 1d size Mag that can be seen here.

http://candlepowerforums.com/vb/showthread.php?t=102584

Unless you *Know* *Exactly* what your doing I would not recommend touching an unprotected recharageble lithium battery. They are very dangerous. If you direct short one of these cells they can vent with flames! Also since you have no protection circuit when you run these cells down past 2.5v your damaging the cells. I have some protected 18650's also and the most they will comfortably puch with protection is around 2amp which is no where nere enough for the ROP high power lamp. I should have a ROP lamp set in my hands Monday and am eager to try them out. Does the stock Mag pedastal Melt with the High power lamp?

Also the only reason why my light is currently unprotected is because the protection circuit I purchased was underated. I have a new circuit coming shortly to test


Mac


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## Alin10123 (Jan 8, 2006)

cmacclel said:


> I'm suprised no one has chimed in here
> 
> Your 2c *unprotected* lithium ROP is cool. I myself have a *unprotected* 2 cell LG2400 18650 Lithion Ion powered WA1111 1d size Mag that can be seen here.
> 
> ...



No, the stock pedastal wont melt with the high powered lamp. 

I will be coming out with an ROP TK kit shortly within month end. When i first ordered parts for my ROP i spent at least $40 in shipping. WIth my TK you will not only have the convenience of ordering from one place, but i'm going to try to save everyone at least $15. But i'm not 100% positive on the pricing yet as i have still to hear back from one last place.


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## eebowler (Jan 8, 2006)

Icebreak: LMAO 

KevinL (anyone): Did you have to mod the C switch to handle the high current or are they better made than the D switches? Thanks.


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## lexina (Jan 8, 2006)

I am currently running a WA1111 on 2 unprotected 18650s in my Mag2C. Would I be right to say that this would lie midway between the ROP LE LOLA & HOLA in brightness?


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## Alin10123 (Jan 8, 2006)

eebowler said:


> Icebreak: LMAO
> 
> KevinL (anyone): Did you have to mod the C switch to handle the high current or are they better made than the D switches? Thanks.



According to my recollection, Kevin said that there's no point in modifying anything for less resistance because for this mod it doesn't make any sort of noticeable difference.


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## Icebreak (Jan 8, 2006)

eebowler -

I hope you're not a EE!


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## cmacclel (Jan 8, 2006)

lexina said:


> I am currently running a WA1111 on 2 unprotected 18650s in my Mag2C. Would I be right to say that this would lie midway between the ROP LE LOLA & HOLA in brightness?




I've read the Hi-Power ROP lamp is a little brighter than the WA1111. The WA1111 is around 800 lumes at 7.2v.


Mac


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## Yooper (Jan 8, 2006)

I dropped a potted 1111 into my 2D-body ROP recently and it wasn't nearly as bright as the ROP 24W bulb.


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## cratz2 (Jan 25, 2006)

So... what kind of brightness and runtime could we expect out of the low bulbs on two unprotected 18650s?

With the TL-3 bulb, I measure 1.2A being pulled from 8.2V worth of 2 18650s so that is about 9.8W correct? The ROP low bulb is 11W so it might be 10% brighter than the TL-3? And since my 17500s are 1100mAh and my 18650s are 2200mAh, I'd get about 90% better runtime (consider the difference in wattage)?

Edit - Oops... just realized that the TL-3 on 2 LiONs is slightly under-driving the bulb while the ROP low on 2 LiONs is overdriving it by about... 20-40% so I'm guessing the ROP will be close to twice as bright as the TL-3?


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## Delvance (Jan 25, 2006)

One of KevinL's earlier posts in this thread states that he started using the low output bulb out of preference as the beam was much whiter etc. A direct copy and paste from his post - 


"400 output Lu for 75 minutes is definitely nothing to sneeze at." That was with the low output bulb.


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## cratz2 (Jan 25, 2006)

Delvance said:


> One of KevinL's earlier posts in this thread states that he started using the low output bulb out of preference as the beam was much whiter etc. A direct copy and paste from his post -
> 
> "400 output Lu for 75 minutes is definitely nothing to sneeze at." That was with the low output bulb.









Right you are... I hate it when folks ask questions that were already answered...


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## PlayboyJoeShmoe (Jan 31, 2006)

Let me apply a  and....

THANK! AW for two 18650 unprotected, and NickZ for a ROP HI...

And I now have a ROP LE. And I VERY HIGHLY recommend it! A couple of guys I've showed it to have said things like "WOW"! (and all in a little 2C!)


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## lexina (Feb 1, 2006)

PlayboyJoeShmoe said:


> Let me apply a  and....
> 
> THANK! AW for two 18650 unprotected, and NickZ for a ROP HI...
> 
> And I now have a ROP LE. And I VERY HIGHLY recommend it! A couple of guys I've showed it to have said things like "WOW"! (and all in a little 2C!)


 
yes, and wouldn't it be the ultimate mod if the new C-sized protected LiIons (3600-3800 mAh) can run the ROP as well!


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## PlayboyJoeShmoe (Feb 1, 2006)

(might at that!)


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## redbird (Feb 2, 2006)

Lexina
I think that is what we are all hoping for. Awesome light output with limited risk.


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## KevinL (Feb 2, 2006)

Me three. 

I'd like to caution people that at this time, it is still a HOPE. I have no idea of the ROP's strike current, and my DMM doesn't have a fast enough sampling rate to capture the startup spike even though I tried. 

That having been said I'm in the C-cell buy as well. I too hope it works. There's only one way to find out.


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## WhiteHot (Feb 2, 2006)

Apparently, the lithium C cells should be able to put out enough current to run the bulb. Maybe one of the soft start ciruits that are coming out can be used to limit inrush current.


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## theamazingrando (Feb 2, 2006)

Wow, runnign off the new C-cells would rock! Do we know when the new cells will be available?


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## AW (Feb 2, 2006)

I believe the protected C cells should be able to provide the continuous 4A draw of the ROP HO bulb without any problem. However, I still have no idea whether they can power up the bulb during the cold spike. My best guess is it will require ' double clicking ' to power up. Soft start circuits will definitely help. I 'll report my findings when I receive some sample cells. Hopefully they will be available around end of March if I have a go.


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## Icebreak (Feb 2, 2006)

Nevermind. I see them now. Li-Ion C


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## nightstalker101 (Jan 1, 2007)

Would it be safe to use 2200mh instead of 2400mh?


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## Lightfantastic (Jan 3, 2007)

I've been using 2200s for some time now. Rather than a PVC tube, run down to the auto parts store and get a lenght of split-loom wire harness wrap that will just fit in the body of the C-mag. The batteries just slide down inside the split-loom and are held in place. No muss, no fuss and no machining a tube to fit inside.

The ROP I made is a 3-c cell with 2 18650s and a spacer. This thing is almost as bright as a million candlepower spot running a 55 watt 6 volt halogen. A 2-c is going to be in the works shortly. These things are just absolutely incredible. I can hardly wait for AW's C size lithiums. Yeeeee-ha!


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## nightstalker101 (Jan 8, 2007)

I just got the parts for this mod. It is extremly bright for the size. I am still useing the plastic reflector, so the beam isn't the greatest, however I am considering getting a metal one. Thanks for the info on the mod.

Nightstalker101


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## plasmaman (Apr 24, 2007)

Sure I'm not the first, but I just found that 4 x Ultrafire 14500 (unprotected) lithium rechargeables will fit into a standard D host - because they are around .15mm slimmer than yer average AA.

Now that means I can run 8 x 14500 in a 2D host using parallel holders from Rob Spook (thanks Rob) which gives me 7.4v and 3.6mah. I stuck a Pelican High in the front end of a low resistance switch, ally reflector and glass lens - and this is visually as strong and white as my SF M6 which runs WA1185 on 6 RC123's. Haven't done a run time yet, but on paper it should get around 50 minutes?

I'm really impressed with this mod - and avoiding the need to tri/quad bore to get lithium power into a 2D.


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## jimjones3630 (May 6, 2007)

Great thread.

Anyone know which DMM would have fast enough sampling rate to capture startup spike? Make and model #?

Thanks, Jim



KevinL said:


> Me three.
> 
> I'd like to caution people that at this time, it is still a HOPE. I have no idea of the ROP's strike current, and my DMM doesn't have a fast enough sampling rate to capture the startup spike even though I tried.
> 
> That having been said I'm in the C-cell buy as well. I too hope it works. There's only one way to find out.


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## maxhawk (May 7, 2007)

jimjones3630 said:


> Anyone know which DMM would have fast enough sampling rate to capture startup spike? Make and model #?



The spike is going to be in the tens of milliseconds and a DMM won't be able to capture this. When I did this measurement for Andrew's hot driver I used an oscilloscope and current probe.


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## sween1911 (May 11, 2007)

Hrm... I'm thinking that this "ROP LE - LOW" recipe might be pretty sweet . . 

-2D Mag
-2 Protected Li-Ions sleeved for the wider D-cell body (PVC Pipe + Tape)
-ROP Low Bulb
-reflector and lens of course.

That whole "Surefire M6-ish output in a sleeper Mag2D body" concept is really getting me thinking. I think with the slightly longer barrel, the 2D-body might also avoid the need to mess with the tailcap. (I think I like leaving my 2C as a "3 x CR123 + Mag5/6 cell bulb" light.)


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## beefy6969 (Sep 17, 2007)

plasmaman said:


> Sure I'm not the first, but I just found that 4 x Ultrafire 14500 (unprotected) lithium rechargeables will fit into a standard D host - because they are around .15mm slimmer than yer average AA.
> 
> Now that means I can run 8 x 14500 in a 2D host using parallel holders from Rob Spook (thanks Rob) which gives me 7.4v and 3.6mah. I stuck a Pelican High in the front end of a low resistance switch, ally reflector and glass lens - and this is visually as strong and white as my SF M6 which runs WA1185 on 6 RC123's. Haven't done a run time yet, but on paper it should get around 50 minutes?
> 
> I'm really impressed with this mod - and avoiding the need to tri/quad bore to get lithium power into a 2D.


 
Hi there, are you using these adapters from Aventrade? http://www.aventrade.com/baad.html

So with 8x14500, the ROP Hi bulb will not ?
What other hotwire bulb options can i do with 8x14500?
If I had a quad bored 2D, thse adapters will fit pretty much any AA battery?


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