Hello,
send me the code please.
THX Ben
red72vw, is that a protected cell you’re using? I ask because this light can pull sufficient current to trip a protection circuit which may reset after a period of non use. This could be what’s happening, not sure though. Outside of this that would be strange behavior.
Hey DB, thanks for the reply. I’m using a LiitoKala INR26650-50A. Which I believe is not protected. It’s odd because I’ve had the tail cap off a number of times and it has only failed when turned a 1/4 turn back and retightened
Sounds like the foam pad is keeping it from making contact. You can try removing the foam/metal disk pad. Just make sure you line the driver switch back up in the button slot if the driver comes loose when you take the head off the tube. See above posts and pictures. Clean threads make sure cell is fully charged. Thats the only sugestions I have
Thanks for the suggestions Robert. Reading back in the posts I saw DBCustom’s comment on making a threaded retaining ring. I would also be interested in purchasing one if you were to make extras, Dale.
Duly noted… have to receive my own light first then I’ll see what can be done.
Yes. The LK cells I've been using have to be cranked down pretty tight to make good contact. In fact I can't measure tail amps on a LK cell because I believe I can't press it down hard enough to compress the foam enough. With a BASEN cell, I have no problem like that - tail amps is easy to get.
I've been using only BASEN cells in it since then. I think the brass ring is needed to make contact, but the foam is unnecessary. I removed that foam from the PK26 for the same reasons. I dunno why it's being used - just to make cell fitting a PITA?
I've done some further run testing. Also modded mine with replacing the CW XP-G2's with XP-G3 S5 5000K's. I got a slight bump in output, possible slight drop in amps drawn (not sure of this). Actually the CW stock LED's had a pretty decent tint - nice white, no blue at all. The XP-G3's look really good in this light - no yellow, or any rings, etc. Tint is as good as the good XP-G2 CW stock LED's. I'm happy with the upgrade, though no big impact.
- With the XP-G3 S5 5000k on a BASEN at 4.23V, got 6.1A tail (clamp meter):
turbo: 2,820 @start, 2,680 @30 secs, lo: 5.8 lumens, mid: 327 lumens, hi: 962 lumens
- CW Stock, on a BASEN at 4.20V, got 6.4A tail (clamp meter):
turbo: 2,650 @start, 2,520 @30 secs
- Parasitic drain is 0.012 mA, which is very low, right up there with the lowest I've measured.
- According to the specs, turbo kicks down to hi at 90 secs -- I measured 98 seconds.
- Did a turbo/hi 6 minute run. BASEN cell dropped from 4.23V to 4.07V, and turbo amps is now at 6.15A tail, up from 6.10A (clamp meter). The light tail stood for the test at room temp, bout 68F. Id' say the light was very warm, not too uncomfortable to hold. It clearly dropped temp after the knock down from turbo.
- Ran it for 1 hour more on hi. Cell dropped to 3.66V, 7.04A on turbo, 1.97A on hi. Checked output on hi after cooling off, and got 970 lumens, so pretty much right there with what was measured on a full cell.
- 20 minutes more. Cell dropped to 3.60V, 7.06A on turbo, 1.98A on hi
Pretty much as expected, though clearly the turbo amps is lower with the XP-G3's. Id' say it should do the 2.5 hrs spec'd on hi, though might do a little better, least with the BASEN cell and the XP-G3's.
Though only a slight bump with the XP-G3's, still it's a better LED, should run slightly cooler, etc.
The MCPCB uses a gray thermal epoxy, not super hard, but I could not get the MCPCB out. I tried some hammer taps on a metal rod that closely matched the opening of the LED wire hole - it could get under a good amount of the MCPCB so really expected to break the epoxy bond, but I started damaging the MCPCB, so had to stop that effort. Instead, I used the hot air station to remove the stock LED's, and set the XP-G3's with the MCPCB in place in the head. I had to crank up the heat to like 450 temp. Not sure why, but normally I use a 280-350 temp to reflow, so had to crank it up. It seemed to work well, checked for shorts before applying power, and tested first with a bench power supply.
ohhh - used a new pencil this time to align the driver as pictured above when re-assembling - worked out well 
I’m not saying leave that disk off permanently, only to trouble shoot. that disk is the spacer that holds the driver in place when the tube is screwed down, but you can remove it temporarily to see if that rubber pad is your problem. If that is your problem, then maybe sand down some of the rubber material so it doesn’t sit so high. Like Tom says, it might be needed to make contact, although the threads are not anodized.
A 3.4mm Dale-made threaded spacer would be perfect
Are the threads square? I don’t have mine yet so I haven’t seen one. I don’t have factory made tools to cut square threads but have had some success making a tool from hss stock, so even if the threads are square I should be able to get it done. Will have to get a brass rod of the correct diameter, shouldn’t be a problem. I’ve got some random 6061 Al that it could be made from as well, don’t see why it has to be brass as the head is aluminum and nothing has to solder to it, it’s just a contact between the battery tube and driver, right?
Oh, BTW, nice work Tom… extended run times with the G3’s and maintaining tint while gaining some brightness is a win every time! 
Sorry my cell phone can’t zoom in as nice as your Canon, but they look trapezoidal. Triangular flattened out on top
Should be able to do that, looking forward to this little light hurrying up and getting here! 
Anyone that owns the black version ? Is anodizing shiny or matte ? Gray version is out of stock .
Interested. Is the group buy still active?
Can I get the code? Thank you!
Thanks everyone for the input. All info and opinions are welcome.
Will check out the “foam pad removed” operation of this torch. May have to de-foam that ring.
Wouldn’t it be easier to simply drop a little solder on top of a flat top cell to circumvent that foam ring a little? Wouldn’t take much of a dome to make it get solid contact…
i have a couple of 26650’s sitting around….put me down for one please
That sounds like a fix worth trying. Thanks
Hello FREEME, is the code still available, surely would appreciate getting in on your deal…
I have almost every DQG light except the 26650 triple and first thing I’ve always done was to take out that foam piece and have never had any bad consequences from doing so.
Matter of fact I always wonder why put them there in the first place, even the little Spy and Hobi had them with the 10180 cells,
Could someone please tell me is this foam thing meant to be some sort of protection from something,
I’ve always wondered about that, and I can’t imagine if it’s for protection from say shorting on the driver perhaps if that’s possible, what a 10180 cell would look like while venting. 
One more quick question, are these lights designed by RicCn?
Always was under the assumption he was the designer DQG lights, probably wrong, but do love the DQG lights, a lot, especially the Spy, amazing bright little light.
If you unscrew the tail cap slightly you will have lockout, provided the foam is in place. It puts a spring action against the cell, pushing it away from the positive contact for just that purpose. It also helps to prevent rattle.