Tuesday, April 24, 2007

SUN Headlight - BE-4X Modification

A friend of mine asked me to do something with a bike headlight he bought recently...

This is what I had to work with:

So I decided to put an Edison into this light. To cut a long story short... this is what I did:
1) Removed old bulb.
2) Fashioned a heatsink out of 3mm thick Aluminium - a lot of hacksawing and filing.
3) Added a smaller circle of aluminium (3mm) to raise the led into the reflector assembly.
4) JB welded the two pieces together.
5) drilled hole for wires to led.
6) JB welded led to smaller circle of heatsink.
7) Fed wires through
8) Jb welded heatsink to reflector module - so that heat is transferred to the whole plastic reflector.
9) Added thermal heat transfer compound around the reflector and in between housing so that heat can be transferred to the outer case of the light.
10) Soldered wires in direct drive configuration.
11) Added 3 mode toggle switch to rear of light.
12) Added 1.5ohm resistor to 2nd mode of switch.

And here are the pics... sorry I didn't really have close up pics of the homemade heatsink itself.. got carried away and JB welded it in place before taking pics.

And here are some beamshots (LOW, HIGH):

The reflector doesn't do the led justice but the overall output is a lot better than the previous bulb. This light was built for spill and a narrow horizontal hotspot as can be seen in the wall shot above. Another option I have is to add an optic inside the reflector to get better throw...
But I guess we'll have to wait and see how it performs...

And yes the 3 smaller leds do work (via original top button) and also flash.