I usually file or sand off the end of the battery tube to re-gain clean bare aluminum so that when assembled the ground is secure. 
I also rarely use thread lube. Never on the tube to head contact and only sparingly on the o-ring. Try to keep the o-ring lube off the tailcap threads. I don’t like the dirty lube getting between my ground connection.
I do that too, but this DQG doesn’t make contact there to complete the circuit. I’ve cleaned the threads and battery contacts though.
I’ve used the light for a few hours over the past couple days without issue.
Today I noticed some flickering in turbo during the “sizzling” or “hissing” sound after running for just a few seconds on a fresh cell.
The noise doesn’t bother me, but the flickering is worrisome. Any ideas?
Flickering is almost always a ground issue.
Hi, Kusie,
usually, I will source LED, cool white at 1A/B/C/D, and nature white 4/A/B/C/D, but usually nature white is not so easy to resource, so, 3 seires or 5 series also will install if cannot find 4 series at that time. for 26650 V3.0, first installed 5B tint (around 4000-4250k), later and current is 3C (4750-5000k).
about nichia 219b/c, first I cannot resource this LED, then I think more important thing is, the optics seems not so fit to richia leds, the hot spot is not clear and the lux is much lower than XPGs at same current set. so, that’s why there have no nichia choice.
thank you for the advise, a new 18650 make by titanium is on plan, seems can smaller than tiny 18650, with 3*LEDs. what do you think?
yes, there does have a little drivers will make noise due to inductor, if you can do, dis-assemble it, find the inductor, resoldering it for a try (but it is not so easy to do), although the inductor is solid one, but maybe a little displacement will lead it verbration due to high franquancy.
maybe the problem is on the inductor not soldering well, the current cannot flow steady or other electric components let the regulator IC cannot work normal. if can, try to make a checking. 
Thank you, George! :+1:
My light seems to function normally, so I will leave it alone for now.
A new even smaller titanium 18650 triple sounds very nice! I’m looking forward to that!
But here’s a request:
Because it can not be driven too hot anyway, because of the titanium (and size), my preference for the leds would be high CRI 219C Nichia’s (in my experience they work fine behind TIR optics). You would do part of this BLF community a great favour if a version of the light would be sold (without warranty of course) in which the ledboad could be removed for DIY replacing the leds, so nothing is glued.
Thanks for the detailed answer! Wow I didn´t know that it can be so hard to source LEDs of your choice - I was under the impression that there is a wide range of LEDs available on the market for manufacturers or wholesale dealers to buy from - seems I´m wrong?
Anyway, since 4000 K is much to warm for me, how can I make sure to get a sample that has the 3C (4750-5000k) LED inside? Can you name a shop that has this version in stock?
Thanks,
Kusie
yishenger,
Thank you for starting this thread and making yourself available to your customers. And a big thanks for making these awesome lights! I have the DQG Tiny 4th Cree XM L2, and this Tiny 26650 and they are two of my most used lights.
I want to tell you what happened to my Tiny 26650. I’ve had this thing in my pocket since the day I bought it. At some point the bezel/lens retaining ring came loose. The o-ring then decompressed and pushed the lens up, pulling the aligning pins away from the PCB and that allowed the lens to rotate and damage all the outer LEDs, rendering the flashlight inoperable. I am devastated. I have a claim in to Banggood and hopefully I’ll be able to get a replacement.
I wonder if you’ve heard, or anyone else has experienced, this problem? I can tell you one thing; if I am able to get a replacement, I will make sure I check the bezel daily!
That sounds awesome!!
However, unlike Djozz, I prefer XPL HI or high-CRI 219B in my triples.
yes, there have limited resource if choice LED bin.
at current, I think there only have 3C now. I don’t know several month later will be.
hi, friend, usually the bezel is tightened as could as I can, I think it will not loosen at using. if it loosen, be care it cannot be tighten simply. you should first put the oring on, then put the optics on the right position, press and hold it, last slowly screw the bezel tighten. yes, you can ask BG to buy a replacement.
There is already the PK26.
I was using my DQG tiny 26650 v3 last night for quite some time without issues .
Today , i grabbed the light , and made a long press to enter turbo , i got light for 1-2 seconds , and then nothing …
I removed the battery , and there was an awful smell .
And then opened the flashlight to see what was wrong (first time removing it’s driver) … I found the positive wire de-soldered from the driver , and the driver in this condition :
It seems it burned 2 leds also …
I’ve been wanting this light for some time……but I admit I’m hesitant based on feedback I’ve seen (since I’m in US and addressing defects or problems would not be conveniently done overseas).
Smaller triple? Oh yeah!
But will it have fiberglass PCB? That’s a serious limitation…
Titanium? For me, that’s a drawback.
How about 18350?
And XP-L2?
I find it difficult to comprehend how using a superior material is a drawback.
Virtually any reason one could name is a hunt in the wrong direction. Small is small, and it comes with it’s own limitations. Same for lightweight. The thermal issues that come from making a light small are there regardless what you make the light out of. Power and output is sacrificed out of necessity, starting at the power supply rather than the material the host is constructed of. Once that is understood, the light can be smaller and lighter in weight. That’s probably easier for me to come to grasp with because I like Titanium.