ZERO RESISTANCE tail cap mod for Surefire Z41 - Deliver more current, reliably

[flashfiend]

+1 I tried the zero resistance cap but the lack of easy momentary on made it too difficult for me to use.

+1

Momentary on for this using an FM Sunlight Module with my SF 6P is very difficult to use.

AND

The momentary takes a bit of work to get at, but depending on how far you twist the tailcap, it could be done easily with a bit of practice(and exercising on your death grip).

Wouldn't really want it for a "tactical" setup or for a light that uses multiple clicks for mode switching though.

+1

Although I am deciding whether I like the harder to press momentary, it does require a bit of a death grip for me. However, since I am using it for an incan setup I don't have to worry about modes. Also I know vision is an unreliable and a biased comparison instrument but this switch is not noticeably brighter than the brass kit for the McClicky.

*****

A few notes:

These will not work well with LED's and IMR18490's in a 9P/C3. These cells are shorter than normal (49 vs 50mm) and there's not enough spring length from most LED drop ins to compensate. Black/protected 18500's work just fine.

Twisty operation is nearly equal across different battery/dropin setups. Momentary can vary greatly depending on the strength of the drop in's spring. Triples, for example, have unusually strong springs and require a firm thumb press to activate on momentary. Malkoff's and factory P60's feel about the same as momentaries on unmodified Z41's.

Want to add these actually work beautifully in a Z41 tailcap with an FM Host (2x18500) and G4 Sunlight Module using AW 18490 IMRs. No death grip needed.

 

[Bullzeyebill]

Received my 0RTCM recently, and like its performance. I do notice some differences in body/cell length in various lights. Bodies too long, or cells too short can be remedied with rare earth magnets used for spacers, or some other type of low resistance spacer. I do not see too many problems with short bodies/overly long cells in some lights, as the module, or LA spring will usually compress enough to handle the issue

0RTCM certainly improves output with my direct driven lights, LED or Ican, and is certainly worthwhile for me. I know that it will improve runtime for my constant current driven LED lights, and will give that edge to LED lights that require a given voltage to run in regulation.

Bill

 

[Phyltre]

Any chance that this might work in a 2x26500 Megalennium or the 26500 tank hosts, with an M2 head? I could see both of these benefiting from this thing. If not, I humbly request one be created! The pocket rocket must reach escape velocity.

 

[Kestrel]

Trying out my new setup, I'm very pleased with it. (Thanks EG!)

The momentary action of the Z41 tailcap is now noticably stiffer - I can see why it's not perfect for some folks, but for me this is a very worthwhile mod. This particular configuration is one of the reasons I changed one of my lights from a bored 6P to a bored C2 - the grip rings on the SF C2/C3's are ideal for the somewhat stiffer action of this mod. An excellent combination. :twothumbs

 

[Kestrel]

Regarding the degree of stiffness of the operation of the 'momentary' in the SF Z41 tailcap with this mod:

Now that I have two comparable setups (Moddoo triple, ZR tailcap mod) in my SF C2 & SF C3, I noticed that the 'momentary' action in the SF C3 is much stiffer than that of the SF C2. This is due to the total length of the cell(s):

SF C2 (1x AW P 18650) vs SF C3 (2x AW P 18500)

My measurements indicate that the end of the 1x18650 setup rides ~0.290" below the tail of the C2, while the 2x18500 setup rides only ~0.200" below the tail of the C3. This results in considerably more spring compression in the drop-in when assembled & operated in a SF C3 / 2xAWP18500, and the spring on the Moddoo triples are very stout. Therefore, the 'momentary' takes quite a bit of force to operate for this configuration.

My solution was to make a 0.050" drop-in shelf spacer using large spring stock, making the 'triple' ride that much higher in the SF C3 host and providing more available internal travel for the drop-in spring. Now that the end of the cell stack will be 0.050" deeper in the host, a much better (i.e. lighter) feel for operation of the 'momentary' is created.

If anyone finds the high degree of force necessary for momentary operation objectionable in their SF C3 / 2xP18500 setup, I would definitely recommend trying this out. It does make the head/bezel ride slightly further away from the body (0.070" vs 0.030"), but I think that the improvement in feel for the momentary is substantial, and comparable to the feel of the internally-shorter SF C2 setup.

Just thought that someone might find this helpful or at least interesting... :shrug:

 

[flashfiend]

I just backed the tailcap out a little more. It seems to have the same effect.

 

[outersquare]

so does this work on a stock 6P body?

I have an otherwise stock 6PDL with an SST90 drop in and using 2xCR123s

 

[Moddoo]

Bump for the forum restore.

 

[pnwoutdoors]

Test battery fitment carefully the first time that you use this tail mod. Screw cap on slowly to be sure that you do not crush your cells.

Since this item has no spring, it seems that the amount of available space is critical for it to work correctly and avoid crushing the cells.

Q: What is the proper space allowance left in the tail of the tube, for this product to make sense? There are many flashlight/tail combinations out there. Do we just purchase the item and pray it'll function properly? In advance of purchase, how do we know?

 

[Bullzeyebill]

Since this item has no spring, it seems that the amount of available space is critical for it to work correctly and avoid crushing the cells.

Q: What is the proper space allowance left in the tail of the tube, for this product to make sense? There are many flashlight/tail combinations out there. Do we just purchase the item and pray it'll function properly? In advance of purchase, how do we know?

Go back to the first post and start reading. Your questions will be answered.

Bill

 

[Eric242]

Is anyone using the Zero Resistance SHORTY? I´d be interested seeing a picture installed for the lack of my imagination with this I think it´s great to run a 18500 in a 123A body (one that´d fit 18mm diameter cells).

Eric

 

[MIC-1]

TL50 with Zero Rez Shorty + 18650 cell.

 

[Eric242]

Thanks a lot!

Eric

 

[Henk_Lu]

The zero-res doesn't work on my bored Z2 host, I tried a Z41 and a C Triad Tail. That's weird, as I ordered a black Z41 especially for that host...

The difference of the Z2 to the C2 or 6P is that the threads are anodized, but the Moodoolar tubes have anodized threads as well and the zero-res works like a charm. Anyone an idea?

 

[Moddoo]

Which cell are you using?
Which drop in are you using?

droid message

 

[Henk_Lu]

Hey Moodoo,

I just have found the problem, it was related to the dropin. The bezel is screwed down completely, but as it seems the dropin is a little smaller and the cell just pushes it upwards when I tighten the zero-res.

I installed the dropin that will be used in that host with the zero-res and it works like s charm now!

Sorry for having bothered you and thanks for your reply!


Sent with love from my iPad using Tapatalk HD

 

[Silgt]

When will the Zero-Res be back in stock?

 

[ElectronGuru]

We are pushing our largest ever run of parts, later this month. Availability starts in january, with brass parts releasing first. The ZR will be along them.

 

[twl]

Is anyone using the Zero Resistance SHORTY? I´d be interested seeing a picture installed for the lack of my imagination with this I think it´s great to run a 18500 in a 123A body (one that´d fit 18mm diameter cells).

Eric

I have both the TorchLab Stubby TL20 with the ZRS for 18350, and also the same light with the TL50 and ZRS for 18650.

 

[tobrien]

We are pushing our largest ever run of parts, later this month. Availability starts in january, with brass parts releasing first. The ZR will be along them.

NICE!