2C Mag Tail Cap mod for AW's "C" cells

[Northern Lights]

After obtaining the cells I noticed a method by which you can use the original tail cap.

AW offers a spacer, a cut and modified original cap is offered my Mirage Man and FiveMega has a flat large cap. I mention the members because each has a unique and very good alternative to the problem of he 54 mm battery in a light made for 50 mm lengths. You should look at each and see what you like. I like all of them.

If you would like to use the original cap without a spacer:

Well, one method is to remove the battery protection circuit.... NO..Oh, NO. I am kidding just to get you to wince a little.

Actually do you remember this mod I posted with pictures?

http://www.candlepowerforums.com/vb/showthread.php?t=143345

I found that if you take a piece of 3/8 inch automotive gasoline hose and cut it off just a tad, a smidgen, barely longer then the tail cap cup and run two loops, an "S" shape of braided copper through the hose to cover the ends and insert it in lieu of the spring you can snug that against the new cell. Just like the pictures I posted but a longer piece of hose. You must de-anodize the inside bottom of the cap and that is easily down with oven cleaner or a sand paper. Now the cap will be about 2 threads short of closing. Replace the OEM O-ring with a fat one to fill the 2 thread gap and you have the original cap looking pretty much normal and at least as many threads engages as the cut down cap. Works on mine.

 

[lexina]

That's really innovative, Northern Lights!

After looking at your photos, my first thought was to look for some hose or tubing. Not finding any and not wanting to start soldering in the middle of the night, I decided to try something else. Currently, I use a small folded-up piece of aluminium foil in my deanodised tail-cap for running 2 X 18650s. I threw in 2 brass nuts into the tail-cap, screwed it on (there's a 1/8 inch gap with the C LiIon), and surprise, it lit up!

I will post some photos later.

Thanks for the inspiration, Northern Lights!

lexina

 

[Northern Lights]

Interesting, you can use anything to take up the space, but use a copper jumper. Copper is so many times more conductive than brass, gold, aluminum. The jumper I just made for this project is not even soldered, just held by the pressure of the compressed rubber hose.
You introduce resistance into your circuit if you do not use copper and that means less lumens! I make a copper contact ceramic pr to bi-pin socket and it measures less resistance than gold plated brass ones on my meter so I believe it is a true concept. I noticed where some have posted they can get single clicks on 5761 lamps with protected batteries. I cannot even get it to go with many clicks with my light unless I add resistance to my circuit using a resistor or NTC. Here it is nicely represented:
http://candlepowerforums.com/vb/showpost.php?p=1825493&postcount=1

 

[lexina]

I agree copper nuts would be better - just didn't have any on hand. Managed to take some pics with my handphone camera.

The 2 brass nuts sitting inside the tail-cap on top of the aluminium foil.




Here you can see the little gap - could be covered with an o-ring.

 

[LuxLuthor]

Good tips.