Just put this together today, an XM-L2 3C on KD DTP 20mm copper MCPCB with brass pill, MTN 10mm FET driver, electronic side switch and recharging/ powerbank functions in 22mm carbon fibre tubing.
I’ve skipped the usual heavy copper & brass on this one and opted for just a brass pill, carbon fibre shell and built the light around an NCR18650B to keep the power sensible too.
A lightweight dual purpose light for camping etc.
Fully potted
ARC Glass
OP reflector
GITD electronic switch
Moppydrv firmware
Red/ Green Charging indicator
Stainless steel bezel insert
Max – 1060 lm
Length – 130mm
Width – 22mm
Weight – 94 grams
Charging Current - 0.5A
Discharging Current - 1.0A
The CF wall is 1mm thick and passes the heat out directly from around the reflector/ brass pill area which is cemented in place with jbweld quite well but the heat does not conduct along the length of the light much, it gets almost too hot to hold in the head area after a while on 100% so I have the stepdown to 50% set to 20s, this design and materials used seems to be a fair balance.
I expected this and that is why I used the tamer cell and smaller driver plus using the light on full blast is detrimental to the powerbank function but still nice to have if needed.
The carbon fibre keeping cool is good for the cell
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Experimenting with the carbon fibre look? I bought the 500mm x 22mm tube for about a tenner, there will be a couple more builds with this :+1:
I’ve used the wrap on a couple of things, usually use it to line battery tubes for better fit
You bought it alone or in a 1*18650 powerbank ?
This design seems to have big parasitic drain and poor efficiency, well below 80% IIRC…
I think HKJ did some test on a similar one, but it seems difficult to find a good circuit in that size format
So I did some rough tests of these small single cell 18650 powerbanks to see what sort of output I was getting in real term use connected to a small USB tester and an Xtar MC-1 Plus charging an 18650 at 1A
