My DIY dive torch, a 3000 lumen LED monster, sucks a bit of juice. I'm feeding it with eight 3000mAh Li Ion 18650 format batteries. Say that five times in a hurry.
At the moment the carrier for these cells is cobbled together with tape, a bit of copper sheet and an old PET soft drink bottle. And it has its issues with intermittent connections, the vulnerability to shorting out against a metal case etc.
Time to fix with a printed custom pro looking jobby.
Printed in a rush so quality is fairly rough (0.4mm layers on a 0.5mm nozzle!) but still took well over two hours to crank out this version. As it threw on the "lid" it dawned on me - the captive design will not let any batteries out once installed but, D'OH, nor will it let them be installed.
Version 2 over the weekend

I was always taught measure twice, cut once. But this is something between the measuring and the cutting - I'm ever so glad it's not a thousand bucks worth of NC milled billet I just got back!
[img]http://www.simonlockwood.net/linky/3dp/batteryfail.jpg[/img]