My bad, you’re right; Henrik K. Jensen.
Any luck with other lights/mods using these cells?
Not yet the machinist I use is slow this time of year. He’s got the tubes from an L6 to cut an extended tube for the Convoy M-3 and the Astrolux MF01.
TS, those sound like worthy mods to accommodate this cell and worth your effort. So far, KawiBoy’s FT03 mod seem the most simple to accomplish and certainly worth while for its other variants. Aloft Hobbies is out of stock on the QB26800 at the moment but is expected to receive more cells in 2-4 weeks.
I cut the bottom off the left side of an Xtar X2 charger so a 26800 now barely fits. Recharged two batteries both drained from a HaikeLite HK4S which has a 2.72 volt cut off. First battery is a Shockli 5500 mah and the second was the QB26800. Shockli charged 5703 mah, QB26800 charged 7124 mah. Both batteries are on their 3rd or 4th recharge.
Thats a great idea for your X2 charger. Those are some nice comparative charging results. Aloft Hobbies is still out of stock on the QB26800. I emailed them again a few days ago to see if and when they plan on re-stalking.
Can you post pictures of what you did to the head and where did you find the spring you used for the tail. I want to try it!
Thanks Tom E. These came back in stock twice before and I missed out. Did you receive their in-stock email notification?
Awesome, great info ! I may try this with mine in the future.
Yep! Surprised I did. Seems like usually, these don't work, or the item never comes back in to stock (on other retailers).
Just ordered a pair. Already have 1 piece from Ali. That FT03 mod looks interesting - gotta check that out. Impressive amps pulled as well.
I guess you got lucky. I never received the notification and its not in my spam folder. Oh well… thanks again for posting. I plan to mod my FT03 fleet but not sure I want to hack into my new copper 90.2 version. Also have a 2 x 26650 light with an addition extension tube that could use some additional mAh. Fun stuff!
I just checked my email and already received a shipping notice. :+1:
Cool! My ship notice came bout an hour ago 
Holy Cow! 14000 posts!! I gotta get-a-life 
is the positive terminal high enough to use them in series? they look exactly what i need for my hotwire lights
Very close but Yes they can stack.
KB - I'm also interested in more details on the FT03 mod. Looks like you saved a lot of space on the driver side.
I'm thinking, but haven't check measurements, you did this:
- reamed out the center of the driver retaining ring to make it thinner so the battery can fit through it (probably can dremel it down)
- tossed the original plastic piece around the driver spring
- removed the driver spring and replaced with a small flat copper slug (or something like this?)
- replaced the tail spring with one that will compress completely flat (dunno where to find one like that, but I could rig of something equivalent I think
Not sure if the first 3 would get the batt as low as you show there in the tube, but it would help. If you used a lathe or something like that to mod the tube or head, I'm screwed.
Update: Ohh, ok. You added bored out copper rings, so you used those for extra spacers, and I see you filled in the gap on the outside with a black o-ring. Think that's the trick...
Why is it that so many 18650 lights have stoopit-long springs but all the 26650 lights I have are contortionist-tight?
I got an old River Rock 2×C light that I tried stuffing in a regular 26650 but it was too tight a fit. Might try “boring” it out a bit with a sander or something, as it’d be worth it to stuff one of these in there and take up the slack later.
If you need to increase the inside diameter of the battery tube use one of these with a drill.
Kewl, tnx!
Thought I’d be grinding away forever with one of those cylindrical sanders.
For the FT03, making those copper rings (or ring) as a spacer, probably fitted under the brass driver retaining ring, is probably not an option with the tools/supplies/skills I have. I could though perhaps use copper wire formed in a loop. As long as the spacer is conductive and relatively even thickness, and doesn't interfere with inserting the battery, should work.