Ok, great! Thanks for the help - think this is the best way to go, just need to check the space in the pill for sure. Heat mgt is always an issue I suppose. I have the EDC (small straight tube type, 18650, similar to the UF2100 but nicer quality) light from Intl Outdoor, and they pulled a 7135 350mA chip from a 8*7135 board to reduce it down to 2.45A because of heat. I put back in a 380mA 7135, so it's about 2.83A now (verified it). But man, this light gets hot quick. Thinking of "pot"ing with thermal grease, somewhere, not sure where - the reflector is kind of odd - has rings around it - thinking of filling them in with thermal grease. What do you think? Would potting in the pill maybe help too?
I guess anything that helps pull the heat away to the body will help, although I wouldn't expect much help from a thick layer of it if you're trying to fill a thick void.
HA! I totally understand! My damn phone does that to me all the time. One time I typed in "Vertical Fest" and it auto-corrected to "Testicle Fest" - needless to say it completely changed the meaning of my text!!!
Lol, that’s one of the better ones I’ve seen, my phone has issues with dialect and slang, it’s taken me AGES to teach it to curse and swear in a broad northern accent.
Tom, I have the host of the light your talking about. It’s always going to struggle with high current, I’m just waiting on an ld25 driver to come in to get it going. If the driver is not soldered to the pill, you could pop it out and fill the cavity in the pill with thermal compound but I’m not seeing filling around the reflector as doing anything other than making a mess tbh. I’ll let you know how mine gets on, but I suspect that even at 2.6a, high is only going to be for short bursts only.
For high output, I think really, we need more mass, c8, c12 etc.
My Tmart one gives 522 lumens at switch-on dropping to 459 after two minutes and since it had dropped to that by a minute or so, it ought to continue around there. Medium is a rock-steady 83 lumens and low about 9 lumens.
The details that I have are in the spreadsheet linked to in my sig.
Thanks for that don. Did you happen to get any tail cap readings and what are your impressions? I’m still finding this light to be my goto light around my house and useful to have in my van. I’m considering sticking in one of the drivers I have on order.
I’ve got a 20mm - 17mm adaptor and I figure if I use the ramping mode I have plenty of control over output vs heat.
Not yet. I will be doing them soon though.
It’s a good relatively small dog-spotting light which works fine at the possible ranges in my local park and doesn’t require the space that a bigger-headed light would - it fits quite nicely in the pockets of my dog-walking coat.
I like it quite a lot. The clip is not something I’ll ever use, but a reversible clip is a nice thing for those that use them.
Output 522 lumens on high with a freshly charged cell - dropping to 459 lumens at two minutes. The throw is respectable at 20600 lux at 1 metre.
Current draw is
| High | 1970mA |
| Medium | 970mA |
| Low | 240mA |
Sounds like it may be running the same driver my Q5 version (Dongrui All-920) is since mine tops around 2.0likes end all they did was droop an XM-L into the same light. Anybody got a pic of driver in this? I believe keltex78 has photos in his thread of the All-920 driver.
-Garry
Mine wins at being least well driven then at 1.5a, its going to get a right good kick in the rear soon though. I also believe mine has a q5 driver rather than one you would spec for an xm-l.
My UF-V3 from Tmart is quite sensitive to battery voltage: straight off the charger 4.2 volts, tail cap draw is 2.25A. At 3.8 battery volts its down to about 1.75A.
High, med, low looks about 100, 50, 12% or so. PWM on med & low is not so bad, but more noticeable than the 1.4Khz nanjg drivers. I like this light, beam profile is clean and good throw, and overall size/performance. I had planned on needing to replacing the driver, but now will likely leave it as is for a while… I have no need to push the output much higher anyway.
I just ordered this light from Tmart for just a hair over $16 after applying some tmart points. Very much looking forward to it arriving next week! 
I just sold my UF C8 to a friend and am getting this to replace it. I never used the C8.
I think your going to like this one johnnymac, its very much my go to light despite my examples failings. My miss’s was also happy to have it on Monday, she commented she like how bright it was and how she didn’t notice it in her pocket.
Partially related funny story:-
Monday night, we were at a bonfire night do at my step sons scout group. Toni’s step mums house looks out over the scout hut, anyway, we’d met up with some friends with their baby and their friends, they needed to check on said baby, so toni handed over the uf-v3 and I passed the zy-t08 to the husband to play with….Andy flashed the zy-t08 about, to comments of “wow” and “look at that”. Debbie flashed about the uf-v3 looking for toni’s step mums house….
Toni was talking to her step mum about Monday night and the fireworks today…… She said it was good, but someone was flashing a torch on the house, the light was so intense, it was like a police helicopter……toni didn’t know where to look, Debbie chimed in “that was me with grahams torch” :8)
The little bugger sure works well. 8)
Graham.
I finally got it!
that was my longest waiting game up till now: 41 days!
It left china a month ago and then it was lost at sea (since it took that long i wonder if it actually was on a ship!)
Now i just have to wait a few more hours to get it dark outside.
Unfortunately i got a 1.6A driver too, did someone follow through with the discussed mod?
I haven’t seen any pictures of the driver?
would be nice to mod it directly and skip the adapter board hassle.
I’ll try to get it apart, but not today. I have to test it at least once outside in the dark! 
Johnnymac did a post on slipping a p60 pill into the uf-v3 pill so a 17mm driver could be fitted.
I’ve got some adaptor boards, just waiting on drivers now, or I may shove in the driver out of my keygos m10 when I get around to swapping that out.
Gords said - "Just thinking about this, when my uf-v3 had an xm-l it drew 2.5a, put in the xp-g2, it only pulled 2a. I asked johnnymac about it and his comment was it’ll only pull what it wants, maybe try hooking it up and testing with a meter before screwing the tailcap on, it’ll take what? Ten minutes at most, you don’t even need to remove the pill, just screw the head off, whole light into some soft jaws, solder away. 
"
Not sure what you are saying exactly here. But maybe this: direct drive the XP-G2 and measure the amps to see what it can take?
Here's pics of my UF-V3 mod:
Brass pill, press fit in, dedomed U2 (experimental):
Shown with original and new driver - new driver is a KD V2 w/1 extra 380 7135, so at 3.4A:
I did basically the same mod to 2 more UF-V3's, but added copper in the brass pill and used a U3 1C, not dedomed though.
Not too happy with this dedomed U2 LED - planning replacing it with maybe an XM-L2 U2.
So you filled the inside (behind driver) of the brass pill with copper? How did you do it and what copper did you use? I'm thinking to do the same thing on a P60 build of an XP-G2. In the past (not P60 pill though) I've cut pieces of solid bare 4ga copper wire (think of the bare copper wire used from your homes circuit panel to a grounding rod) placed in the pill and filled around with solder (I had more area to fill).
-Garry
Garry - I do have pics, don't have time to post right now. At the time, didn't get the copper discs yet, so was able to get bare copper ground wire (Home Depot guy gave 2 foot to me!) - multi-strand, but each strand is about 10 gauge or so. So, cut/sanded carefully and fit in 5 pieces (most I could fit before blocking the wire holes), jammed in tight, then dropped some solder blobs on them, heated them up w/flux and the solder just flowed down/around the tightly packed pieces - worked pretty good. Since then, I'm using the Etsy/ebay sourced copper discs, 5/8" 18 gauge, and usually stacking them, soldered together, then epoxy them in the pill up against the top. Got to notch them on each side using a dremel grinding attachment for the LED wires to pass through. Then I used the stock KD V2 wires (nice 22 gauge, 150C rated), but now I'm using 22 gauge silver tinned teflon coated wires.
Both copper discs and teflon wire sources provided by Old-Lumens!! He's posted his sources in that weekend marathon of building the MagLites Niche lights.
So, not being too dumb, but
did you just “piggyback” it??
Yes - piggyback'd one on the under side - underside is usually better than top side because of battery clearance issues. With the UF-V3, had the space underside. On my Jacob, used the 20mm driver from I-O, piggyback'd all 3 7135's then double piggyback'd one to bring it up to 2.45A because driver was only 3 7135's. Double piggyback'ing is more tricky, also not certain about the thermal path because if you read the specs on the 7135, there is heat generated and the soldering to the board acts as a thermal path. some guys cut the middle of the 3 legs because it's ground, same as the backside of the chip, but I always leave it in, soldering both the small leg and the back tab because it's better thermally. Piggyback'ing has to put more stress on the thermal paths. I'm thinkin all the more reason maybe to pot the driver/pill for stacked drivers, dunno, but I'm sure there are lots of opinions on that...
Hey tom, sorry, I missed this.
What I meant was, take the head off the light. You expose the star. Unsolder the star, solder the xp-g2 in there then test with the meter before buttoning up, I’m thinking it’ll hopefully just pull what it wants rather than 3.4a. If so, call it done. If you are thinking of replacing a star anyway, throw an xp-g2 in there, I think you’ll really like the result. I know I wouldn’t put an xm-l back in there now, not for anything. :bigsmile: