10x Vero 13 build - Request input

Hello,
After posting previously about some ideas I had for a light and hearing back from people on this thread:
https://www.rollitup.org/t/2x-vero-29-cob-1000x-individual-diode-combination-request-advice-input.827033/#post-10477544

I've reconsidered my original plan and gone with something much simpler and more efficient.
I'd love to hear back and see once again, what I'm missing, or what I could optimize better.

My new plan is for a 10x Vero 13 (4k 80CRI), on a 12" x 12" aluminum plate.
Parts:
1x HLG-185H-C500A $75
10x Vero 13 $8x10
12" x 12" x 1/8th" Aluminum Plate $17
6x 3" x 3" x 2" Copper CPU heatpipe coolers $40 (6 used heatpipe coolers I bought off ebay)





Fan arrangement: unsure

I'd like to run the Vero 13's at 500ma.
According to the datasheet, this will put the VF at 32.5V, the Wattage at 16.3W, and the output at 2060 lumens, assuming a Tj of 25C.

I plan to arrange the Vero 13's in 2 rows of 5 (1.5" dia, 1.5"x7.5" per row) on one side of the plate,
and the heatsinks in 2 rows of 3 on the other side (3"x9") above the cobs.

I'll probably mount both the heatsinks and COB's with a thin bead of epoxy around the edges for strength and a thin layer of heatsink paste over the inner portion for heat transfer.

These heatsinks are for 125W Xeons CPU's, so I think it should be safe to say each would keep a 100W load under 60C, given the proper fan on top (standard 90mm CPU fan).

I'm probably going to build a shroud/tunnel around them and use a couple 120mm fans from the side.

If this is successful, I should have a 20,000 lumen led light at 163W+PSU losses.

Please let me know if you all think this is doable, especially with regards to keeping a Tj of 25-30C.

Cool design, looks like you have done your homework! Is this for autoflower or photo flowering lamp?

As far as Tj 25-30C that could be tricky. Thermal resistance of the package is .9C/W at 500mA. It will be dissipating about 16W so that adds 14.5 to the temp of the hottest part of the package (Tc). So if ambient is 75f (24C) and hottest part of the heatsink plate is 28C, that brings us up to Tj of 42C before we consider the thermal resistance between the COB and heatsink surface. If you lap the heatsink surface and use a very thin layer of top notch thermal paste that should be very minimal, but I would just call it Tj of 50C which is a very good running temp for a grow lamp.

Looks like a solid plan. With the HLG driver you have room for two extra Vero's to make a 3x4 arrangement. If it becomes too much light or power it can always be dimmed. In my experience the Vf is lower than stated in the specs (which is a good thing).

Be safe with the 400V of that driver.

The Vero 4000K is already excellent for flowering, no additions needed.

I can't remember where, but I read that the 4k vero is similar in red light output to the 3k cree lamps. Is this correct, or is there more to it?

I'll have the aluminum plate in a few days. I'm thinking about trying to braze the heatsinks to it with a MAP torch. Any thoughts?

Sorry to keep adding questions here, but I also haven't considered coverage yet either. This will be over a 2'x2' area. Could someone give me formulas for calculating coverage angles and light heigth requirements Pretty please?

Also a note on safety. I'm going to hot glue over each solder joint before powering on. Will it be safe for me/the psu, to discharge the capacitors by bringing the terminals with an insulated screwdriver? I assume there will still be a deadly amount of current left after the unit is turned off. Will I blow the output discharging this way?