COB LED DIY Build Journal

[PDX Joe]

Okay, I finally started building my grow light. I am building a 3' wide x 3' deep x 5'-8" tall grow closet. My plan is to use a SCROG.

The light will be built with:
(4) Cree CXB 3590, 3500k, CD bin
(4) Arctic Alpine 64 Plus
(1) Meanwell HLG 240-1750b
(1) Meanwell APV 12-12
Ledil Angelina reflectors

I like the clean look and well organized design of the full metal enclosures you often see the professional COB grow light builders use. So, I decided to figure out how to build a light with a full metal enclosure. I found a 24" x 24" x 4" galvanized steel electrical box on Zoro.com. You can order metal boxes from them without knockouts/ holes, so you can decide yourself where you wants holes, etc. They are a bit pricey, but this box allows me to add more COBs in the future. The 24" x 24" size also allows me to perfectly space the COBs out to evenly cover the 3 x 3 closet, and all the components are neatly tucked away. The steel box is a nice heavy gauge metal, so it will not flex or bend... rock solid.

Today I cut the fan holes and COB holes with a hole saw. I also started drilling out two sides of the box for ventilation. This is a bit tedious, but I'll admit I'm a bit OCD, and I think the effort will be worth it. So, here's some photos of the progress.

 

[VegasWinner]

nice looking fixture you have there. I see you will mount everything inside the enclosure. peace

 

[PDX Joe]

I drilled the rest of the ventilation holes. I tried to match the total open area of the ventilation holes to the open area of the heatsink fans. Also, I cut a spot for the power switch and fuse with a Dremel.

 

[coolj]

how much for the case?

 

[PDX Joe]

$100. Free shipping. Yes, it wasn't cheap. But, it's built well. It's 14 gauge steel.

 

[Airwalker16]

Very cool. Wish mine was in an enclosure honestly.

 

[PDX Joe]

Here's the new grow closet build out. I needed to take a break from the LED build to get the basement buttoned up. The small door will be for the reservoir.

 

[PDX Joe]

I'm still on the COB build pause trying to finish the grow closet. I cut some reclaimed doors down and installed them. The plywood wall sheathing has been installed and painted. All the walls and ceiling are insulated. BAM! I'm calling this room the grow bar.

 

[PDX Joe]

Okay, back to the COB grow light build. I've started laying out and rearranging the components within the housing. I wanted to finalize the organization before I start drilling holes to mount the different parts. I also don't want to crowd anything to ensure everything gets a bit of air circulation.

 

[BM9AGS]

Closet looks awesome. From my experience you'll always want it bigger. Did you use drywall or cement board? Will it be self contained air tight?

 

[PDX Joe]

Closet looks awesome. From my experience you'll always want it bigger. Did you use drywall or cement board? Will it be self contained air tight?

Thanks. I have a ways to go on all the final details, but it's starting to get there. I definitely wanted to go bigger. But, it was a compromise with my wife. I got to build a grow closet if I remodeled the basement in the process. Win, win.

For the walls and ceiling I used an exterior grade plywood with a nice solid veneer on one side, so it doesn't have knots. I primed it with the Kilz made for wood and plywood and I'll put a final coat of a bright flat white paint on too.

The closet will have a passive air intake grill down low with a HEPA filter on it, and I will have a carbon filter and 4" inline fan up top, so not air tight. Actually the inline fan will be hidden under the stairs and I'll probably insulate around it to keep it nice and quiet.

 

[PDX Joe]

I did a quick test fit with the reflector, COB holder and heatsink to get the alignment with the holes figured out. I need to sand off the metal burrs around the holes and paint the enclosure. It looks a bit crude right now.

 

[PDX Joe]

I attached the drivers and other hardware to the enclosure. All the electronics and heatsink are mounted to the ceiling of the enclosure. The bottom of the enclosure simply covers the enclosure and surrounds the COB reflectors. The Arctic Alpine heatsinks will hang from the enclosure ceiling.

 

[PDX Joe]

I also spray painted the enclosure and started attaching hanger eyelets and fan grills.

 

[PDX Joe]

And I wet sanded the heatsinks to 1000 grit fineness.

 

[LED Light User]

Nice Case Build Up
I take a seat

 

[BM9AGS]

Some DIY guys said watch out for a thermal interface material that will be caustic with the aluminum.

What is the cob spacing in that case?

Looks great

 

[PDX Joe]

Some DIY guys said watch out for a thermal interface material that will be caustic with the aluminum.

What is the cob spacing in that case?

Looks great

Hmm, strange about the thermal interface. Is it corroding/ pitting the aluminum? Do you know the type/ brand? I have Arctic Silver 5 grease and the stick-on pads from Cutter. I was going to use the Cutter pads because they seem easier and cleaner.

The COB spacing is 17" from center to center. It seemed like this would give the most even spread in a 3' x 3' closet based on the light angle from the Angelina reflectors.

 

[BM9AGS]

Great spacing IMO.

I'd reach out to some of the more
Geeky members for that info. I can't recall who was looking in to that.


I'd be 100% sure you wouldn't have issues with arctic silver ceramique

 

[PDX Joe]

I wonder if the problem might be with the dissimilar metals of the heatsink and COB holder instead of the thermal compound. In the presence of moisture such as high humidity the aluminum and steel could create a galvanic couple and result in corrosion. Although, if this was the case then I would think we'd here a lot more complaints? Hmm...