As promised, today i build another LED light. I named it Freeze Ray, because of the blue LED and because the heatsink got even colder then room temperature.

So i startet with a big ass Heatsink, i got from the scrapyard.

I started by drilling 3.2mm holes and drilling an M4 thread into it. Later i used M4 stainless steel srews to mount the LEDs. Also mounts for the Power supply and cooling were added.

These metal bands have perfectly sized holes for my screws and they can be bend into any shape you like. After these two, i added a third one, going across the top screws, to later mount a second power supply (12V, for cooling Fans).

The power suplly comes from an old laptop (stripped the case and had it lying around, way overpowered for the one Fan) and the Fan is used too. Thats why i decided to mount them both with zip ties, in case i want to exchange them in the Future.

This is the Front of the final light.

In the middle, you see a 60 Watt blue Led 465-470nm, 8€

outside you see 4 red emitters 10 Watt each 620-625nm, 5€ each

the 4 red ones are in series, and that string is parallel to the big blue one.

the first test showed 25.6°C at a roomtemperature of 26.7°C after an hour of running.

So for everyone, who wants to build something similar: here is the Budged:

blue led: 8€

red Leds: 20€

Led power supply: 27€

Cooling Fan: about 10€ (free for me)

Cooling power supply : about 5€ (free for me, but any cheap 12V supply will do)

Heatsink: no idea (free from scrapyard)

Total: 70€ (45€ for me)

Pro tip: never forget thermal paste and there are smal thermal fuses, made for motor overheating. They open the contact at about 60-70°C and would make a great addition to your Led lamp. Just wire them in series at the AC side of your LED power supply and the LEDs go out, when they overheat (maybe Fans will fail). My next Versions will surely have this safety feature.

see you next mission

-aka