10W LED lamp uses the Cree XM-L LED. Parts : aluminium reflector 40mm, (plexi-)glass circle 40mm, Cree XML 10W chip on star heatsink, 2 more star heatsinks, 4x4mm 6mm high tactile switch, "Strong light torch driver board" on Aliexpress, ribbed heatsink approx. 40x25mm (from old VGA card).

The new driver board has C-type USB socket for charging the battery, and also the driver circuit for 10W LED.

Print the 3D parts. Get a heatsink from an old VGA card and cut it to size. Drill two 1.5mm holes 19mm apart 7mm from the edge of the heatsink. Mount the Cree LED with 2mm screws on the heatsink and the two extra star heatsinks (2.5-3mm padding) used as spacers, this ensures that the LED is in focus with the reflector.

Replace the tactile 4x4mm size switch on the PCB with the 6mm high "copper pillar" switch.

Wire the parts together, test the working, then remove the battery before the final assembly.

Mix some epoxy glue, start with the PCB, then glue the coolplate in position. Insert the reflector, check focus and close the assembly with the plexiglass circle and the ring. I prefer plexiglass over glass, not so perfect optically but does not break...

Wait couple of hours until the glue hardens.

Finally connect and glue the battery, cut a piece of 2mm thick real leather to size and glue it around the battery.

I used batteries from an old laptop battery, they come 2 parallel welded.

The brightness beats car headlights.