DIY dual mode board/cob light completed

TerrapinBlazin

Well-Known Member
I’ve been posting about the build process over in grow room design, but that forum doesn’t seem all that busy and I’m hoping for some final thoughts now that it’s done over here in DIY, which I just discovered today.

This was kind of a lot for my first DIY light build, but I’m glad I jumped into the deep end. Altogether the light uses 4 3000k cxb1820 cobs (that I salvaged from some lights I bought from Lowe’s back when I didn’t know much about lighting) and two Atreum “quantum boards” (HLG has that name patented but it’s the same shit) with 288 Samsung lm310b 3000k diodes in each board.

I got B series drivers (HLG-240h-54b for the boards and HLG-120h-48b for the cobs) and set up a dimmer box that controls both lights, and I installed a switch box to control each driver with toggle switches, so each driver can be operated completely independently.

So I’m making this thread just to review. My goal with this build was to make something that would replace my 600 watt HPS in my closet. Taking into account the total wattage of the drivers and the insane lumen per watt rating on the boards, I think it will be sufficient. If we assume a 600 watt HPS produces about .9 GPW and that these modern LEDs produce 1.5, then they should give me a pretty identical yield.

Now I want to know how to get the most out of this light. I ordered another board and a HLG-120h-54a driver for it and I’m going to use that for the tent. I know that LEDs need to be closer to the canopy than HPS lights, but I can’t have it so close that I lose coverage. I also read that with LEDs you should shoot for at least 32 watts per square foot of canopy, and my canopy is about 7.5 square feet (6 plants in 7 gallon nursery bags trained through a trellis) which puts me comfortably above that number.

Here are some pics. I may still work on it some more, but any more work I do on it would be purely cosmetic, like a nice finish on the wood and definitely a bigger box for the potentiometers.

Thanks for reading. I’ve been interested in building an LED light for the entire year, and finally got it done with a little over two weeks left. This one was complicated, but I knew that if I completed this light that I’ll be able to build anything that I can afford the parts for. Now I should be good on lights until I decide to further ramp up my indoor growing, and that won’t happen until I have a bigger house.

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Gond00s

Well-Known Member
I’ve been posting about the build process over in grow room design, but that forum doesn’t seem all that busy and I’m hoping for some final thoughts now that it’s done over here in DIY, which I just discovered today.

This was kind of a lot for my first DIY light build, but I’m glad I jumped into the deep end. Altogether the light uses 4 cxb1820 cobs (that I salvaged from some lights I bought from Lowe’s back when I didn’t know much about lighting) and two Atreum “quantum boards” (HLG has that name patented but it’s the same shit) with 288 Samsung lm310b in each board.

I got B series drivers (HLG-240h-54b for the boards and HLG-120h-48b for the cobs) and set up a dimmer box that controls both lights, and I installed a switch box to control each driver with toggle switches, so each driver can be operated completely independently.

So I’m making this thread just to review. My goal with this build was to make something that would replace my 600 watt HPS in my closet. Taking into account the total wattage of the drivers and the insane lumen per watt rating on the boards, I think it will be sufficient. If we assume a 600 watt HPS produces about .9 GPW and that these modern LEDs produce 1.5, then they should give me a pretty identical yield.

Now I want to know how to get the most out of this light. I ordered another board and a HLG-120h-54a driver for it and I’m going to use that for the tent. I know that LEDs need to be closer to the canopy than HPS lights, but I can’t have it so close that I lose coverage. I also read that with LEDs you should shoot for at least 32 watts per square foot of canopy, and my canopy is about 7.5 square feet (6 plants in 7 gallon nursery bags trained through a trellis) which puts me comfortably above that number.

Here are some pics. I may still work on it some more, but any more work I do on it would be purely cosmetic, like a nice finish on the wood.

Thanks for reading. I’ve been interested in building an LED light for the entire year, and finally got it done with a little over two weeks left. This one was complicated, but I knew that if I completed this light that I’ll be able to build anything that I can afford the parts for. Now I should be good on lights until I decide to further ramp up my indoor growing, and that won’t happen until I have a bigger house.

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Looks super nice I just dont like the wood
 

TerrapinBlazin

Well-Known Member
Personal preference. I’m a professional carpenter/woodworker for my day job and I had a shitload of maple and mahogany. I took my inspiration from a high end guitar amp head with a maple cabinet, just without all the super time consuming dovetail/dowel/mortise and tenon joinery. I played with doing it out of angle aluminum and keeping it open, but all that drilling/screwing self tappers would have been brutal with my carpal tunnel. One day I’ll teach myself to weld.
 
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Gond00s

Well-Known Member
Personal preference. I’m a professional carpenter/woodworker for my day job and I had a shitload of maple and mahogany. I took my inspiration from a high end guitar amp head with a maple cabinet. I played with doing it out of angle aluminum and keeping it open, but all that drilling/screwing self tappers would have been brutal with my carpal tunnel. One day I’ll teach myself to weld.
It’s fine I just rather have it metal because it’s less flammable
 

TerrapinBlazin

Well-Known Member
No question there, and I agree, but I rationalized doing it this way with my musical instrument inspiration. None of these electronics get nearly as hot as an amp head smaller than that packed with 6L6 tubes. Even wooden amp cabinets don’t catch fire when a tube or something blows out so I figure as long as there aren’t any short circuits and there’s good heat dissipation I’ll be fine. I’ve never seen a fire on a music instrument that wasn’t started on purpose, lol
 

Gond00s

Well-Known Member
No question there, and I agree, but I rationalized doing it this way with my musical instrument inspiration. None of these electronics get nearly as hot as an amp head smaller than that packed with 6L6 tubes. Even wooden amp cabinets don’t catch fire when a tube or something blows out so I figure as long as there aren’t any short circuits and there’s good heat dissipation I’ll be fine. I’ve never seen a fire on a music instrument that wasn’t started on purpose, lol
its fine just gotta make sure you have no loose wires and make sure you done everything right and safely then u should have no problems i have a fan blowing on my drivers because they do get warm
 

TerrapinBlazin

Well-Known Member
I’ll need to do that in the summer. It’s not an issue now but in the summer when it’s in the closet I’ll have a desk fan blowing over the drivers. In the veg tent I have a cumputer fan in one of the duct ports to move air through it, but this light won’t be in the tent for long.

I bought one more of those boards today and a HLG-120h-54a to run it and I think I’m just going to stick the driver to the top of the heatsink with double sided glazing tape.
 

Airwalker16

Well-Known Member
Looks great. P.s. the way you get lED closer without losing coverage, is by SPREADIBG THE DIODES OUT. Which is why strip builds are so popular. Perfect example is green genes Garden on YouTube's last grow.
 

TerrapinBlazin

Well-Known Member
Yeah I could see doing a build with four of those boards spread out further, and maybe even making it another dual mode light by throwing in some cxm22s or something. I haven’t looked too much into strips, just because I’m growing in small square-ish areas.
 

TerrapinBlazin

Well-Known Member
Cutting it ain’t a problem. I have a 12 inch sliding miter saw and you can get modified triple chip grind blades for cutting metal on amazon for pretty cheap. Then you can of course either drill it and screw/bolt it together or weld it, which I would prefer to do. I’ve been meaning to get a decent wire feed/mig welder and learning how to use it, but a decent one from miller is still like 500 bucks. I don’t have 240 at my house so stick welding is out.
 

Airwalker16

Well-Known Member
Yeah I could see doing a build with four of those boards spread out further, and maybe even making it another dual mode light by throwing in some cxm22s or something. I haven’t looked too much into strips, just because I’m growing in small square-ish areas.
Strips come in 1, 2, & 4 foot lengths brother.
 

TerrapinBlazin

Well-Known Member
Strips come in 1, 2, & 4 foot lengths brother.
Got any in particular that you recommend? Like a certain model? I was only vaguely aware of strips and thought they were more for larger scale grows running 1000+ watts. I’ll definitely consider them for future builds. Seems like strips would be really easy to put together into arrays with simple metal brackets.
 

Airwalker16

Well-Known Member
Got any in particular that you recommend? Like a certain model? I was only vaguely aware of strips and thought they were more for larger scale grows running 1000+ watts. I’ll definitely consider them for future builds. Seems like strips would be really easy to put together into arrays with simple metal brackets.
You can make any wattage light you want man
There's ones from cutter from Mark @welight or tons on arrow and digikey. they're made by Samsung or bridgelux. Go to led gardener com page to get the basics.

 

TerrapinBlazin

Well-Known Member
Nice. I gave it a quick read and it looks like strips are ideal for people that may have trouble sourcing boards, but those atreum boards are on amazon prime so these days anyone can get a 288 lm310b board with included heatsink and wire from amazon for $70.

Looks like they don’t make strips with lm310bs in them, just lm51cs. Looks like I need to do a lot more research, because as well as I understand cobs and boards now, I do not have the same understanding of strips. It seems like strips would be easy to DIY, especially if you can get the aluminum PCBs done for cheap. I know a guy who builds supercomputers for los alamos national labs and he could probably make me the PCB I need.
 
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GKS

Member
I’ve been posting about the build process over in grow room design, but that forum doesn’t seem all that busy and I’m hoping for some final thoughts now that it’s done over here in DIY, which I just discovered today.

This was kind of a lot for my first DIY light build, but I’m glad I jumped into the deep end. Altogether the light uses 4 3000k cxb1820 cobs (that I salvaged from some lights I bought from Lowe’s back when I didn’t know much about lighting) and two Atreum “quantum boards” (HLG has that name patented but it’s the same shit) with 288 Samsung lm310b 3000k diodes in each board.

I got B series drivers (HLG-240h-54b for the boards and HLG-120h-48b for the cobs) and set up a dimmer box that controls both lights, and I installed a switch box to control each driver with toggle switches, so each driver can be operated completely independently.

So I’m making this thread just to review. My goal with this build was to make something that would replace my 600 watt HPS in my closet. Taking into account the total wattage of the drivers and the insane lumen per watt rating on the boards, I think it will be sufficient. If we assume a 600 watt HPS produces about .9 GPW and that these modern LEDs produce 1.5, then they should give me a pretty identical yield.

Now I want to know how to get the most out of this light. I ordered another board and a HLG-120h-54a driver for it and I’m going to use that for the tent. I know that LEDs need to be closer to the canopy than HPS lights, but I can’t have it so close that I lose coverage. I also read that with LEDs you should shoot for at least 32 watts per square foot of canopy, and my canopy is about 7.5 square feet (6 plants in 7 gallon nursery bags trained through a trellis) which puts me comfortably above that number.

Here are some pics. I may still work on it some more, but any more work I do on it would be purely cosmetic, like a nice finish on the wood and definitely a bigger box for the potentiometers.

Thanks for reading. I’ve been interested in building an LED light for the entire year, and finally got it done with a little over two weeks left. This one was complicated, but I knew that if I completed this light that I’ll be able to build anything that I can afford the parts for. Now I should be good on lights until I decide to further ramp up my indoor growing, and that won’t happen until I have a bigger house.

View attachment 4436523View attachment 4436524View attachment 4436525View attachment 4436526
Your build is awesome!!!! Really nice
 

Airwalker16

Well-Known Member
Nice. I gave it a quick read and it looks like strips are ideal for people that may have trouble sourcing boards, but those atreum boards are on amazon prime so these days anyone can get a 288 lm310b board with included heatsink and wire from amazon for $70.

Looks like they don’t make strips with lm310bs in them, just lm51cs. Looks like I need to do a lot more research, because as well as I understand cobs and boards now, I do not have the same understanding of strips. It seems like strips would be easy to DIY, especially if you can get the aluminum PCBs done for cheap. I know a guy who builds supercomputers for los alamos national labs and he could probably make me the PCB I need.
Cutter is where you need to go if you're wanting highest efficiency chips. They have Nichia, J series Cree, all kinds of different diodes. They're called Sol-strips and quite honestly, boards are great, big fan, but strips can give you a far far FAR GREATER spread and overall evenness in lighting for your canopy. Even if you do multiple 2'X2' fixtures for say like a 4'X4' area so you can raise and lower each of them to meet the growth. Rather than one single fixture build using 4'wide of 4' long strips.
 

TerrapinBlazin

Well-Known Member
Well I decided to jump right in and start saving money right away, so as soon as I built my single board light for my veg tent this afternoon I took down the HPS in the closet and put up the big light. I did the switch right after the HPS went off for the day. It is really bright. I doubt it’s gonna have much effect on the yield at day 43, but I’m really interested to see how it compares with the HPS when I chop these plants down and throw in the next batch of clones. I don’t think I’m going to spread out the canopy as much on the next batch, and try to encourage more longer colas.


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