Sorry but here is what im getting, 3 cool white 100 watt cobs and 3 warm white cobs, 3 drivers that were linked in the original light you made on this thread. An amp heatsink that's around 12 ×13 but that's it as of now. My problem is im just blueprinting so im all over the place on what I wanna do, but I appreciate the help. Still haven't decided whether to make two separate lights or not. Im thinking 6 cobs might be too much on one but I know nothing of this.
I will be scavenging a lot today so I will post pics to give a better understanding, once I get home i will take a pic of the heatsink and the area im trying to light up as well. But thanks again I appreciate any help you can give me brother, im just trying to learn all I can.
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Sounds like your off to a good start with the heat sink. If your using the same chips as me, then you will want to have a six LED rig, it will generate more heat than 3 LEDs but will give you about 70% more light, just drive the LEDs in parallel pairs off the drivers.
The easiest and cheapest build would be to put everything in one case and use one heat sink with the 6 chips arranged about an inch from the edges of the sink. Acquire a metal box to put everything in, or make an enclosure using heavy aluminum flashing (used for widows and roofing) that you can get from building suppliers. Flashing is easy to work with and you can cut it with tin snips, if you distort the metal cutting it, just put it between two piece of wood and hammer it flat again after your finished cutting. You can order strips of aluminum flashing custom bent for a reasonable price and about a buck a bend and they do it right there. Say you ordered a strip of flashing 5" wide with a 90 degree bend on one edge and a 3/4 to 1" edge, so you would have a piece of 5"x 1" "L" shaped angle of aluminum flashing say 6' to 8' long. Next you would wrap it around the heat sink to make a box with the heat sink making up the bottom, cut 90 degree triangles out of the top corners with tin snips and screw the flashing to the heat sink along the bottom edges. Now you will have a 5" high metal box with a 3/4 to 1" lip around the top edge that you can bolt another flat 12" x13" piece of aluminum flashing (or other heavier metal) for a top, drill or cut holes in the middle of the lid for two 3" or 4" computer fans blowing down onto the heat sink from the top, you can mount the fans inside or outside the box and stick them on with silicone caulking. Screw the lid onto the side edges with self tapping sheet metal screws and cut ventilation slots in the bottom of the sides where the air exits the heat sink fins.
You could put this light in the center of the garden with out lenses or reflectors for a foundational top lamp, you can add other lamps from other angles later. If you think about it a bit you could order your flashing a bit wider with an additional 30 degree bend along the bottom edge to act as a reflector, just line the inside with aluminum tape. If you want to keep it simple though, add a reflector later. You should get almost 100W from each pair of chips, say 300W total, if 25% of the energy is converted to light that leaves about 230W for the heat sink to dissipate and your sink is 12" x 13" = 156 sq/in. So the heat sink dissipates 230W/156sqin = 1.47W per square inch and of course were not counting the radiator fins on the back. If noise is an issue, 12vdc fans run quiet and can be under volted to run even quieter (fans inside the case are quieter than those outside), you can use a 7 or 9 VDC wall wart adapter to run the fans if you want. You should actively cool this rig, but I don't think you will have to drive the fan(s) hard, bigger fans can run slower and quieter.
