After much research I decided to tackle making a DIY LED light for my new tank. I owe a lot to Hoppy and others for the knowledge and gumption on LEDs. Of course, I found ways to make it hard anyway.
Heatsink/ structure - 8' of 1.5x0.5 inch aluminum(EBay) $20
15x 3w LEDs (Ebay) $41
Driver (DealExtreme) $14
Various other supplies ~$8 so far
I also purchased some tools, such as a $20 tapping set. I had other things I used, such as a drawer center support which works great (again, thanks to Hoppy for that idea.)
I started by cutting the aluminum to size, and then set up a router jig. I read online about using a router on aluminum, and the advice was to use a slow speed and WD-40 for cutting oil. I figured I would probably ruin a router blade in the process.
It took a fair amount of time, but was actually pretty easy. It actually worked just as well without the cutting oil, and without it the shavings blew away and I had better visualization. And the router bit is still in great shape.
Eventually I ended up with a big aluminum asterisk.
Next I worked on the mounting bracket. The drawer support came with a bracket to mount the slide to the back of the cabinet, so I used it, after trimming the corners of the aluminum to fit it, and trimming the bracket to look nicer.
Mounting the other end to the aquarium stand took a little problem solving, since I wanted it on the corner and the stand was a little wonky. The tapping set ended up being invaluable, as I just put in a couple screw holes that I could screw some clamps to.
I did end up using a counterweight system. It is internal in the clamp, and I just used a screw with a nylon bushing for a pulley on the stationary part of the slide, with one end of the cord connected to the bottom of the sliding portion. I needed about 8 lbs, and Iím still trying to find a neat weight package. A dumbbell worked, but my wife needed it back.
I routed insets for the LEDs. I didn't go too deep, but it should still help so the LEDs are not as visible.
Here i placed one LED in the inset. I need to figure out which LEDs are which before I plaster them in.
I debated a bit one the best way to finish it. I sanded out the extrusion marks with 60 grit paper. It left a rough but very bright finish. I resanded with 220, and it was flatter looking but felt smooth. It would have been fun to go to 600 and higher to make it mirror, but it seemed too much work. So I sealed it with clear lacquer to stop corrosion, and there it is.
Still to come: plastering the LEDs down, soldering them together, wiring in the driver, final assembly.