Led headlamp 3 Watts

thingiverse

I'm using a simple LED headlamp that's powered by a 18650 battery. It works well with my 18650 battery holder, which you can find on Thingiverse here: https://www.thingiverse.com/thing:2317031 To make this headlamp, I used the following parts: - A Star-3W LED that puts out 290 lumens - A clear Turlens emitter with a 23mm outer diameter - An aluminum strip that's about 2.2x120 mm (check out the photo) - A KAN-15 push button switch - A resistor with a resistance of around 0.8-1 Ohm - Thermal grease to help transfer heat from the LED - Four screws that are each about 2x10...15 mm long - All of the parts I used can be printed in 3D on two axes The efficiency of this resistor as a current limiter is around 84-91%. However, the aluminum radiator inside the box is too small for a 3-Watt LED, so it's best to use this headlamp at an outer temperature below 15 degrees C.