Adapting 20mm driver pill to 17mm

I just got a UniqueFire UF-V3 and while it is an awesome little performer, it is way under driven (1.74A on high). Obviously I want to replace the driver but the pill in this light only takes 20mm drivers. This poses a problem as there are no 20mm drivers I know of that meet my needs. I first thought I could just place a 17mm driver inside behind the 20mm driver but the space inside the pill is only 4.5mm deep. Besides, being an all aluminum pill, soldering a good, dependable ground to the driver would be difficult. I brought out my bin of parts and figured a P60 pill might just fit inside of the original pill. I can work with that! Here is what I did…

Here you can see that a brass p60 pill will almost fit inside of the 20mm pill of the light. What we need to do is grind down the circumference of the brass pill a bit plus enlarge the inside diameter of the aluminum pill. Leave enough material so that they can be pressed/hammered together for a tight ground for the driver.

Here is a pic of the modded p60 pill compared to a stock version. I ground down the emitter side lip so that the brass pill will sit tight against the inside rear of the aluminum pill. I’ve also ground down the sides of the brass pill so that it can be pressed into the aluminum pill.

Using my rotary tool and cutting bit, I have cleaned up the inside of the pill and removed some of the inside wall to allow the brass p60 pill to be tightly press fitted.

A dab of fujik fills any air gaps between the top of the p60 pill and the back inside of the original pill.

Now that your brass insert is ground down and your pill opening is opened enough to allow a high pressure fit you can place the two in a vice and press seat the brass insert into the original pill. Optionally you can carefully tap them together using a block and hammer.

Onced pressed in by vice or hammered in with a block you will end up with an aluminum 20mm pill with a 17mm brass insert for your new driver that can easily be soldered to.

I’m quite sure this could be used in any light with a pill meant for a 20-21mm driver. Hope it helps some of you. :wink:


Great ideal Johnny, thanks for posting.

So, where can i buy some p60 pills then?

Nice one johnny, I’m planning on fitting my m10 driver in my uf-v3, but I might do this and throw a 3a driver in instead.

I have a bag full of empty P60 pills. PM me if you want some.

Great, thanks!

I get mine from CNQG for 50¢/piece in a 5-pack.

Easing the edge of the brass pill might allow it to press in without scraping burrs of Alu. Tighter fit with less pressure needed.

the burs were only around the wire holes in the back of the emitter plate in the pill. They need to be removed for the face of the brass pill to sit flush against the emitter base of the aluminum pill. Both brass pill and inside walls of aluminum pill need to have material removed for them to fit together. It is extremely tight and had to be hammered in. ;)

ha, I like that, a bit of hardcore rough hobbying!

Mine :wink:

Great simple mod, thanks Johnny!

Nice job JM. Thanks for posting the information.

I put in a nearly full P60 pill in the MXDL SA-16 today at work. This light has a pretty long spring so i though that is I moved the driver out a little then used a short spring it would be the same.

I used the belt sander at work and removed alot of the threads till it was close and used the press to push it in the pill section of the MXDL. Then heated both of them and flowed some solder in the gap so that I would know there would be a decent contact between aluminum and the brass.

Heres a few pics.

sorry pics were taken with Iphone

Nice job! :beer:

Thanks, thanks for the idea!

Good simple fix JM. Thanks for posting it!

Thank You, Thanks You JM. This is the solution I was looking for. I have a UF-V3 and 2 friends bought them as well. Also, I know there are at least a couple of more BLF'ers that are interested in having someone do this type of mod - Rusty Joe, ZW99GT. Gotta order those drop-in's and a few more drivers. I'm leaning towards the KD V2 at 3.04A, may be a little too much for this light because of the poor heat mgt, but the brass P60 insert will definitely help.


Is this the same P60 -> ?

It says 26.5mm, and 5 for $3.50. I don't see anything smaller on CNQG. The specs are sparse to say the least, I assume the 26.5mm is the width, but it looks like the one you used is a smaller width?

That is the exact one. The 26mm refers to the reflector size that will attach to the threaded portion when making a full p60 drop in. You only need the part you linked to. :slight_smile: