Let's talk DIY lights


Was able to finally get a small strip build done. 5, 560mm bridgelux eb strips in 5000k for a small 32"x 16" mother and clone cab. Forward voltage is about 22.1 on 700ma driver. With dimming cable unhooked she’s running right about 80 watts.

Should be about perfect for the application. I think I have about $85 into the build, but also used a few things I had leftover from other builds. The good thing about these strips is that you could easily add more or safely increase the driver current to 1050ma to increase the power. The 700ma was where the manufacturer test data was listed, and I feel it was pretty good for the target application.

These strips are available in 1120, 560, and 280mm lenghts and are all 24mm wide. So they are ideal for actually fitting inside of 4’ or 2’ tents. And it was way less labor intensive than a cob build.


I love it dude @dbrn32!




I’m gonna have to send this one down the road soon, but I plan on running it a few hours and grabbing some temp data before. Bridgelux suggests they can be run without heatsink and efficacy is around 160 lumen/watt for this particular strip. Those are cob equivalent #'s at a fraction of the cost. I mounted them on 1.5"x1/8" aluminum bar stock with some 2 sided thermal transfer tape on I picked from amazon for around $7 for 30 yards. It was way easier than drilling/tapping holes and jacking around with transfer compound.

I ran it for about 2 hours and the bars were warm to touch, so the tape was definitely pulling heat. No indication that anything was out of place with temps, but I only had ir gun with me. I can take tc and heatsink temps with my multimeter that will be a lot more accurate. So we’ll see what comes out of that. For now I’m thinking these strips are a legit hassle free way into diy.


Yea I was thinking about it, could these strips work better for me than COB’s? Lol there’s just so much to consider!!!



I think better would be very subjective. In my opinion, I feel the strips are way easier to build and probably the cheapest way to get the most even canopy coverage. Even if you were close on cost, the flexibility of the strips in that you could add or subtract a strip or 2 could easily sway the cost per watt.

The only real disadvantage I see will be the difference in light intensity at any given spot. You take a 50 or 75 watt cob, and there is gonna be some light directly underneath it. So the guys running one cob per square foot would probably argue that all day long. In this case, there would be a huge difference in build cost though. And the intensity could be at least partially mitigated by running fixture lower because you wouldn’t have the hot spots as cobs do.

Which is better, jury is probably out. The strip builds like the quantam boards are know to be a little weak in the corners. There’s just less diodes there so naturally less light intensity. To be honest, you may have seen a little bit of the same issue with the build we were looking at for you. 4 cobs in a row over 5 feet is just about 1 cob short of even us all. We could’ve spaced a bit further than the 10"-12" that’s recommended to offset, but them you don’t maximize light mixing as well. It’s the same but different if you know what I mean.

Lemme take a look at some driver configurations and get a round about for some numbers. We’ll see how they stack up dollar for dollar…


You’re always SO HELPFUL @dbrn32, thank you so much for everything you do dude! I really appreciate it, all of it!



I don’t know why but these seem like they would be good for lower side lighting, or are they too hot?


No problem!

Quick glance tells me an hlg-240 will run 5 1120mm (44 inch) eb strips at 1050ma. I figure on 2" aluminum bar stock you would space them about 2" apart giving you fixture about the size of 2x4 fluorescent running About 230 watts. You could probably expect to run this fixture in veg about 8-10 inches or so above your plants maybe? Which should create good even coverage about the size of the fixture.

The real benefit here, is that if you wanted to increase the watt per foot, add more strips or tighten up the spacing.

Price estimate as follows:

5 bridgelux eb strips in 5000k $73.50
1 hlg-240-1050. $58.00
1 roll adhesive heat tape. $15.00
20’ of 2"x1/8" alum bar. $20.00
8’ of aluminum angle. $12.00

Figure a few bucks for wire, wago’s, and some hardware too. And I didn’t include shipping. Metal prices quoted from online metals. Otherwise that should about cover it. More or less strips could always change up driver configurations and fluctuate price a little too.


I don’t think they’re very hot at all when configured properly. I’ll try to get some temp measurements soon.

I think the intensity is a little underestimated from the pictures. Unless you’re growing with a butt kicking cob set up or something, I’d probably run these as main light and not have to worry about side lighting. You try to implement the side lighting to cover gaps in canopy coverage. These guys make it much more effective to eliminate those gaps.

But ya, if you wanted to tinker around with 1 or 2 to add as side lighting they will function well


@ktreez420 I wasn’t thinking like this initially, but you could also do something with the 560mm strips. They are half as long, half the voltage, and half the cost. The driver configurations are similar, so the hlg-240 would run 10 of the 560’s instead of 5 of the 1120’s.

I don’t really see an advantage or disadvantage of using one or the other except for fixture shape. The 22" strips could provide the same coverage orientated in the opposite direction using twice as many.

The main advantage of the smaller strips would be to create a smaller fixture. Whether it be for a smaller space or just a different shape in general.


@dbrn32 i’m just about ready to make a move. getting excited and anxious!


Nice! @BIGE You were looking at doing something with cxb’s right?


Holy crap just spent 2 hours reading this in the car. Don’t know how much I retained. @dbrn32 has me convinced on building my own LEDs. I was going to use a 600w MH/HPS but doing the math those electric bills don’t sound amazing. Gotta get a few things straight before I know how big my space is. Could be like 3x6 or maybe I Wana use a tent, not sure how tall my space is tbh. I might throw a question out later tonight.


No problem! I’ll help in anyway I can.

One thing to consider when going to into rectangular shapes is there are very few single fixture options. Diy would provide some viable options, but you would probably want to look at building 2 separate fixtures to keep them manageable.

Even going hid, there’s not really any one fixture that would fill a 3x6 really well. You’d probably be looking for two 400-600 watt fixtures.

Just something to keep in mind moving forward.


Thats what im using. 2 600w hps and a 200w led angled for sides. There doing amazing. Sooo frosty. The mix with the led really makes a difference. Id highly recommend using a mix of hid and led for sure. Its just amazing, hands down. I posted pics a couple days ago. @Carnako or anyone else is welcome to check out my post. Happy hrowing and goodluck :v::seedling::grinning:


So I did some measurements and mulled over the whole smell issue and I think a tent will be my “solution” or the closest thing I can get to one. I can fit a 48x24x60 tent. I could go slightly bigger but the tents available in 48x32x60 don’t seam as quality and I’m growing autos so it should be enough room.

So I watched some led intro vids from growmau5. I’d like to fill that space with a pretty good amount of ppfd like 600+ is pretty decent right? My electricity is cheep as far as national average ( I think) it’s 9.5cents/kwh. Not sure if that makes running cobs at a certain wattage more efficient in terms of watts/$.

Im still not sure what assembly of these fixtures entails but I think I’d be up for it if it saves on start up costs. I know how to solder and I just got done wiring a 20 amp breaker for a sub panel to my grow room with 3 outlets and room for more if any of that experience carries over.

Another thing is I want ventilation of this setup to be possible ( obviously) so if the needed amount of wattage is going to get that space too hot to vent then I need to lower my standards I suppose. I guess let me know if that setup is realistic.


It shouldn’t take anywhere near 20 amps to light a 2’x4" and add a fan. If you plan on adding a/c and dehumidifier, maybe that would push it. I don’t have a par meter, so we would have to do some research and take some other people’s word for it. But I’m game.

When designing an led circuit, some things have to take priority over others. If you want the most light per watt, you run them soft and just add more leds to hit your target coverage. This runs build costs up though. So the alternative is to buy less leds and push them a little harder. You’ll get more light this way, but it will consume more power. There isn’t exactly a right or wrong way, it’s just deciding whether your build is going to target the best bang for your buck up front, or in the long run.

I’m thinking the textbook 1 cxb 3590 or citizen clu 048 per square foot would put you there, but I’d have to check on the outputs at different currents before I said for sure. You could probably run 6 vero 29’s a little harder, which is kind of their thing. I’m sure a strip build could be configured, but I’d have to look more into them as I’ve only done smaller ones. Probably the easiest would be something with quantum boards, but they are hard to catch in stock.

Soldering isn’t really required much anymore. But the fact that you can and have at least a little experience with electrical components will help. Let me do some digging around and I’ll post back.


@Carnako 3 quantum boards at around 100 watts each will do it well. I would say 3500k if you want to veg and flower under the same light.

These are available in kits or as individual components from horticulture lighting group. Give them a look when you have time. There is a 3rd party par test on YouTube, should tell you everything you wanna know about the par levels.

I’ll keep looking for other options as well.


Looks like 8 Cree cxb 3590 at 1050ma each would put you well above, probably more like 800 ish average. I would expect similar performance out of the citizen line of cobs.

To save a little cash, the vero 29se could probably get you to over 600 average using 6 at 1750ma. The difference here would be you see a little more fluctuation across your canopy. But I think you’d still be decent.

I’m not finding a lot on the strips yet. There’s just to many different configurations. I’m sure there’s something out there though.


I’m just gonna take a wild guess at the bridgelux eb strips and say about 10 of the 44" strips at 700ma and maybe 8 at 1050ma.

I could only find par data on 4 strips in 2x4 tent, it was running about 350ish average at 4 700ma and 4 inches above canopy. Figure doubling up on the strips would get you more than double with the reflection of the tent and greater chip density. You’d probably be good for the 600 at 10-12 inches.


Samsung makes strips similar to the bridgelux, uses the same diodes as quantum board. But They are much more expensive. I think per diode the qb is more cost effective. But I’d throw it out there if you wanted one of the higher efficiency builds.