10W LED Light Project - Walkthrough

[Watashi]

I recently started a project to build a 10W LED light for a saltwater fish tank. I ended up using 8 1.2W Avago LEDs, 2 6500K White, 2 470nm Blue and 4 455nm Royal Blue. Each LED has a vf of 3.2v@.350mA. Power supply is 7.5v@1.8A.

First step was to draw out my circuit, I used photoshop to do it, but mspaint would probably work fine. Here is a picture of the circuit.


Now I used a razor and cut out all the black parts of the now stencil. using the stencil I traced the circuit onto a 6x9" piece of copper clad board.


In the etching tub, cut to size.


This is right out of the etch, rinsed and mineral spirits to get rid of the ink. (eww weird oxidation)


Finished product, ready for component placement and soldering. (This was not the board I used in the final product, but it's the only one I have a picture of at this stage)


Now I need to make the heat sink. I used 3/4"x1/8" aluminum strip and cut it into 3.5" pieces, I cut the base from a 2"x1/8 strip. then I bent 2 pieces to form the switch box. Assemble the switch on the plate and I'm ready to assemble.


It was all put together with Arctic Silver thermal Adhesive, assembly is pretty straight forward, add glue hold in place, let dry.


Now on to attaching my lights. First I tinned all the solder pads. I used the same thermal adhesive as I did for the heatsink and glued the metal slug down to the PCB. After letting the adhesive dry for about 30 mins. I applied heat and a touch more solder to connect the leads to the PCB.


Lets see how bright this sucker is!


Ok, looks like everything is working so it's time to assemble. I glued the PCB to the heatsink, again giving it time to dry. I drilled a hole through the board and heatsink to the switch and added wires to the +- terminals.

[Watashi]

Switch wired in and silicone applied to all connections, then taped


Lens installed with silicone, sealing in the circuit to protect it from moisture. I had the lens made at eplastics.com


Finally fully assembled and on, first picture is with a florescent light overhead and the second is in the dark.




I'll have a couple more pics coming when I install the light on the tank.

[junkie]

That's rad. I wish I was a DIYer.

[ShellMaster]

what was the build cost? i need to make a 10 inch fixture and you made it all look semi doable haha

also what are the exact parts list you used? like drivers and powersupplys ect, this is very interesting!

lol 2nd to last and 3rd to last pics ahahaha!

[Watashi]

Build cost was about 80 dollars. I had to buy a lot more material than I needed to do this one board. My total investment was closer to $120, I needed to buy silly stuff like wire, soldering iron, enough ferric chloride to etch about 100 boards...haha. EDIT: I just threw together a spreadsheet with a list of the major stuff and what they cost with links to everything. Download it here (excel .xlsx)

These are the lights I used except for the current Royal Blue, I got some of the last ones of the 452nm spectrum, I think they are 455 now, not a huge difference.

White
Blue
Royal Blue
I chose these LEDs due to their ease of soldering without a reflow oven, the leads are large and easily accessable for a standard fine point soldering iron.

The resistors were also ordered from mouser at the time I bought the LEDs, they were only 18 cents a piece so I ordered plenty extra just to be safe.

I used a 6x9" piece of copper clad board, I bought mine locally at fry's but this is similar to what I bought.

The aluminum for the heatsink was bought at Home Depot, both pieces cost about 18 dollars, but the 2" piece was 28" longer than I needed. You may be able to find shorter less expensive pieces elsewhere if you look around. I used a dremel with a cutoff wheel to cut the pieces to meet my design needs.

The Arctic Silver Silver Thermal Adhesive was also pricey for what it's job was, I only needed to glue metal together, but due to the application I had to make sure it would conduct the heat accordingly, so I opted for the expensive stuff.

The power supply was also bought at Fry's, it's just a Universal 3v-12v 1800mA Power Converter, I can't find a link for one on their site, but here are some similar ones. I set mine to 7.5v to handle 2 LED in series. Power supply was $15

I did not use any drivers, since my excess voltage was only 1.1v and I could get away with using a very small resistor, 3.16ohm.

[Watashi]

Couple more pics of the install, I didn't get a before picture, but it was just a white 9w cfl.



And one a bit closer up. Sorry for the grainyness of the camera.

[willp2]

Very nice. I'd imagine its staying nice and cool. I dig the lens cover, very creative.

[jessegarcia28]

I would be interested in buying a replica. It would be perfect for a 15 gallon i have. LMK if you would be interested in making another one.

[Watashi]

Yes, I would be happy to make a replica. I probably won't be able to get to it until after the holidays, But I'll keep you updated as to when I can get started.

[jessegarcia28]

ok.cool. I appreciate ur kindness. hope to hear from u soon & happy holidays

[Shemp]

what size and typr of nano tank is it on?

[Shemp]

awsome project btw.

[Watashi]

This light is on a 6gal. Eclipse style tank.

[splitkooks]

how is everything doing now? better growth?

[Watashi]

Been on for 2 days now and everything in the tank is responding better. All Zoas are open and nothing is stretching out trying to get better light.