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

Moddoo

Flashlight Enthusiast
Joined
Nov 19, 2008
Messages
1,243
Location
Minnesota
Here is a hot new part for you guys.

Do you run a:
- Direct Drive Triple XPG
- SST50 pocket rocket
- SST90 pocket rocket
- Incan hotwire
- Anything with high current needs
??????????

Todays high current lights are in need of a tail cap that can handle the load.
There are no tail assemblies with any spring, or switch that can deliver the full power to your drop-in at when dealing with a 5-10 amp load.

Until now.

This is a simple twisty mod to get the power out the front of your light.

We have tested many of the available options.
These can provide HUNDREDS OF EXTRA LUMENS OUT THE FRONT compared to anything else out there with a spring or switch when dealing with the 5-10 amp loads that we are now seeing daily around here.

Installation:

-Simply pull the spring from your aluminum cup.
-Pull the aluminum cup
-Drop in the brass ZERO RESISTANCE mod
-Tap pin into place tightly
- Enjoy your light brighter than ever before.:party:

A few words of caution:

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.

This mod should work perfectly on any single cell bored surefire, and many other lights.

This mod will truly deliver all of the current to your drop-in that is available.
Use care when lighting up your direct drive setups the first time.

THESE DELIVER OVER 200 EXTRA LUMENS OUT THE FRONT on my Direct Drive Triple XPG drop-ins compared to a McClicky.



FOR SALE NOW
http://www.oveready.com/surefire-upgrades/oveready-zero-resistance-z41-upgrade/prod_150.html :thumbsup:

FOR SALE NOW
These will ship after 6/17


Z41-zero008.jpg


Z41-zero044.jpg
 
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Cool, but in the case for your tripple XPG, if its feeding it that much higher voltage, couldn't that damage the drop-in? Sometimes resistance is a good thing because it acts like a resistor and keeps things from receiving too much power.

Can you post current draws of the McClicky vs your creation for your moddoo 3x XPG drop in.

Also since there is no spring, couldn't it potentially crush a protected Li-ion's PCB, especially for longer cells?
 
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Cool, but in the case for your tripple XPG, if its feeding it that much higher voltage, couldn't that damage the drop-in? Sometimes resistance is a good thing because it acts like a resistor and keeps things from receiving too much power.

Can you post current draws of the McClicky vs your creation for your moddoo 3x XPG drop in.

Also since there is no spring, couldn't it potentially crush a protected Li-ion's PCB, especially for longer cells?

This is completely safe and recommended when used with an AW 18650 2600mAh cell, as specified to the customers of this Drop-in

The OP states the necessary precautions.
I can vouch for my single cell bored surefires and 18650s of all flavors.
 
Does it work with the M2 bezel?... you know how the M2 has the soft foam and positions the drop in a little more forward in the light?
 
Does it work with the M2 bezel?... you know how the M2 has the soft foam and positions the drop in a little more forward in the light?

This would be very dependent on the:
host
cell length
drop-in spring(s)

give me details, and I'll try to replicate it.
 
Moddoo I just purchased 2 of these from your website.

So, no spring is required at all right?


Thanks,
bigC
 
Interested, but I assume there's no clicky/momentary on function?

Seems nice, but I need more lights that can:
1) Deliver a high enough current than what the McClicky can handle(5+ Amps).
2) Dissipate the heat well enough to be run for a while.

In other words, I need to get one or more of your heatsinked modules before I can justify buying this(please tell me this is coming soon).
 
I'm very curious about this, and the price is certainly right. I have a couple questions though about my particular setup. I have a direct drive SST-90 drop in from Nailbender; would this mod allow me to reap the benefits of using an IMR cell? (while being attentive to the temperature of course)

I sure wish you sold typeIII HA black Z41 tailcaps to match the beautiful light you sent me. I guess I'll have to get the normal one and the 17mm o-ring. Could you make this mod as one of the switch options with the Z41 tailcaps you sell?

Absolutely loving the light, by the way. :twothumbs
8cf5eb63.jpg
 
I'm very curious about this, and the price is certainly right. I have a couple questions though about my particular setup. I have a direct drive SST-90 drop in from Nailbender; would this mod allow me to reap the benefits of using an IMR cell? (while being attentive to the temperature of course)

I sure wish you sold typeIII HA black Z41 tailcaps to match the beautiful light you sent me. I guess I'll have to get the normal one and the 17mm o-ring. Could you make this mod as one of the switch options with the Z41 tailcaps you sell?

Absolutely loving the light, by the way. :twothumbs
8cf5eb63.jpg
Be very careful about that. I got a little around 7A with a wire spring mod to the module, but the emitter quickly turned blue. Even if it's fully potted, the potting isn't exactly great thermal mass and isn't a substitute for copper.

Also, I had the dome on the emitter loosen up because of the extreme heat from the module.

Still, it could be fine if you leave the spring on the module alone. The difference in resistance between the Brass + McClicky and this tailcap mod shouldn't be big enough to kick the current up that much.

Again, this little upgrade is nifty, but there simply aren't enough modules in the P60 size that can provide adequate heatsinking outside of custom made ones.
 
Mine's potted but I got that for the added shock resistance, I doubt it does much for heat transfer (haha, heat transfer to what?). All I can do is put a copper strip around the base of the module so that it actually contacts the body of my light.

But if I'm correctly reading what you're saying, the module spring is the next weakest link after the tailcap...so how much will this mod benefit if at all?

I don't want to fry this rather pricey drop in so if I'm just asking for trouble then I'm not going to waste my time and money. Obviously I would be watching for tint changes and monitoring the heat though.

The question is, how much heat will be created by my little handwarmer and how long will it be able to run at those temperatures? The high heat will result in a drop in output anyways so is it best to just stick with what I'm doing? I'm comfortable running it for 10+ minutes as is.
 
Mine's potted but I got that for the added shock resistance, I doubt it does much for heat transfer (haha, heat transfer to what?). All I can do is put a copper strip around the base of the module so that it actually contacts the body of my light.

But if I'm correctly reading what you're saying, the module spring is the next weakest link after the tailcap...so how much will this mod benefit if at all?

I don't want to fry this rather pricey drop in so if I'm just asking for trouble then I'm not going to waste my time and money. Obviously I would be watching for tint changes and monitoring the heat though.

The question is, how much heat will be created by my little handwarmer and how long will it be able to run at those temperatures? The high heat will result in a drop in output anyways so is it best to just stick with what I'm doing? I'm comfortable running it for 10+ minutes as is.
I had already used copper foil tape around the module, and made sandwiched layers with AS5. The root of the problem isn't thermal transfer of heat to the host, but rather a lack of thermal mass immediately below the emitter. That hollow pill simply isn't sufficient to heatsink an emitter running on more than 3 amps.

Dave would also want to remind me that attempting to monkey around with one of his modules to reach a higher current is an area that he doesn't want to be in. His modules were intended to be run as is for maximum efficiency while maintaining a long lifetime.

And I swear I'm not just saying that because he might show up at my house with his SST-90 modded Maglite pointed 3 inches away from my eye socket:ohgeez:.

Again, I'm thinking this little upgrade would be nice, but you would need a light engine that can handle the heat. Something like an SST-50/90 driven at 5A mounted on a copper slug with some regulation to make sure the current doesn't go higher. Then you could go nuts and run it on an AW 2600mAh cell without worrying about blowing up the battery while still having a ridiculously bright light with a respectable runtime.
 
I think I'll accept the limitations of my drop-in and it's hollow pill and run it as is. However, I think this mod would still be very useful for high output incan setups where heat is not the enemy. :devil: Then I'll really be putting those IMRs to use.
 
I think I'll accept the limitations of my drop-in and it's hollow pill and run it as is. However, I think this mod would still be very useful for high output incan setups where heat is not the enemy. :devil: Then I'll really be putting those IMRs to use.
Yes, but then the problem will be high voltage, which I believe is needed to run those lights.
 
Yes, but then the problem will be high voltage, which I believe is needed to run those lights.

Depends on the drop in but I've got some options I think (still learning):
2xIMR16340
2xIMR18500 with extender

Let me know if I'm barking up the wrong tree. I'm looking at various Lumens Factory lamp assemblies. There appears to be choices in both 3.7 and 9 volts.
 
This mod means the light essentially becomes a full twisty without a momentary option correct?
 
This mod means the light essentially becomes a full twisty without a momentary option correct?

Looking at the design, it appears that the momentary function would remain, as long as the new piston is able to move freely within the cylinder created by the tail cap.
 
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