OK, spent more time and money than I thought of course. The copper was scrap so purchased by weight. I picked up an additional 25 heatsinks plus 2 150mm fans and some other parts for $20 cash.
This is a 17" x 11" x 1/16" (about 1.6mm thick) piece of scrap copper. It was very shiny until I tried cleaning it with 1500 grit emery cloth which scratched the surface up pretty bad. Aluminum hollow tubes are riveted to the copper and have the wires routed through them. All pictures so far are from the top of the fixture.
Above is pre-wired for 4x Vero 29's 4,000K on corners of copper, they will be driven by an HLG-185H-C1050b. There will be some unused capacity available, but at 1050mA there isn't much I can do with it other than buy another Vero 29 but don't think I need it at this point. and haven't decided on what to do for a fuse. In the center an unnamed blurple cob on a separate driver, it's a 30W model that's running around 22W, meh, so what, I wasted a little money. There is wiring for blue 20mm star LED's which I don't have yet, and which I don't have a driver for. Maybe 12W Luxeon M, or a pair and some near violet. I started with normal 18 gauge wire but realized fishing it would become difficult so moved to the teflon coated wire which pulls easier, it's just more difficult to strip the ends off.
The heatsinks on the corners have flat bottoms while most have
The blue LED's can go under the 4 heatsinks which are not on the corners.
The corner heatsinks will get thermal grease applied to them at the same time I attach the COB's to the bottom. I have a small amount of arctic silver but maybe not enough for everything. The heatsinks at top center and bottom may be attached with thermal epoxy as well as any other heatsinks I need to attach.
Don't use "hardware store" chinese taps. Go to a machine shop and ask where they buy theirs. For aluminum cutting fluid I use Tap Magic specifically for Aluminum. Drilling and tapping that many holes gets boring. Now that I have over 100 holes on the tap I used it may be time to retire it.
No, I haven't attached the COB's. I want to get a flux pen first, I have a nice 60W soldering iron and good tips, it just takes too long based on the one COB I did attach.
I have a 150mm fan that I will either try to run at 5V or put it on a PWM so there is less noise. No idea if it is necessary. Each of the heatsinks weights about 1 pound (550g?). There is easily room for 6 more heatsinks but that might just be a waste.
This is for a cabinet with 2'x3' interior, height between bottom of fixture and the top of the growing media is 38".
If I add red's or far red they will be on their own light bars, not worried about that right now.
Any tips for finishing this build appreciated.
-90 degree lenses and / or diffusers,
-fuse location and size
-Thanks!
congrats RIU graduate.
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. Lol
