DIY LED strip build for 4x4

[ocg420]

Hello Everyone,

I recently decided that I would go the DIY LED strip build route after reading some of the guides available here:
http://ledgardener.com/diy-led-strip-bu ... bridgelux/.

At this point I am basically trying to decide between 2 different builds:
A. Samsung F-Series LT-FB24B 4′ LED Strip Build – 4’x4′
B. Bridgelux Gen. 2 BXEB-L1120Z 4′ LED Strip Build – 4’x4′

But open to new suggestions from the community as I'm brand new to the scene.

Ultimately the Bridgelux build is appealing due to the lower price point. Having said that, I don't want to sacrifice quality and it's not as easy to tell how good the end result will be with the Bridgelux build - Gen 2 isn't included as part of the Parallel Strip Build Tool right now.

But in either case, I was wondering: Should I go with the HLG-600H-48A instead of the HLG-480H-42A? I see the above link recommends the 480H-42A for either build, while the Parallel Strip Build Tool recommends the 600H at 75%.

Also, I had a couple specific questions about the frame:

Would I be ok to use 3/4" x 3/4" angle aluminum even if it's painted? Found an affordable option at Home Depot:
https://www.homedepot.ca/product/alexan ... 1000675512

Would I be ok to use Metal U-Channel Satin Clear 3/4-inch x 1-inch x 8 Ft. instead of the more premium aluminum heat sink options recommended as part of above guides?
https://www.homedepot.ca/product/alexan ... 1000675839

My plan would be to use 4x 46" pieces of angle aluminum to create the outside square, and 11 BXEB 4' strips would be mounted to 46" strips of the 3/4" x 1" u-channel.

Does the above plan make sense so far?

Thanks in advance for your help.

[ATPinMotion]

Greets and welcome!

It sounds like you are on track for a a build that will run right along side an HLG- 550 but for half the cost!

Key points - with the FB24's you will want a 48v driver

With EB gen 2's you will want a 42v driver.

This is a key difference, so when you compare 2 EB strips at 1a each to one FB24 at 2a, even though the current is equal the FB is getting 20% more power (48v vs 40v)

Personally I would recommend (2) 240w or (2) 320w drivers (or one of each?). This will give added flexibility and redundancy for little added cost. (Maybe even use one driver for 2700k strips and the other 3000k or 3500k?)

Keep in mind the FB24's are almost 2" wide (~40mm), and generate twice the heat of an EB gen 2 strip - you will probably want a better heatsink for running those guys, which again increases the cost of the build, unless you just use 2 of the L channels per strip.

In terms of the heatsink, it really depends how many strips you are running.

Take a hlg-240-42 driver and 8 EBgen2's for example. The driver makes ~6a and the strips each get .75a. Assuming you use thermal paste/tape, the diodes will probably run in the high 30's Celsius and the painted L channel high 20's.

Take the same driver and power 6 strips, at 1a per strip temps will go up (probably ~10 degrees?)

@T-Time fabbed up some FB24's - he said at 2a the back of his heatsinks were 55°C, and these were proper heatsinks (I can find a link to the thread of you like).

So a lot of it depends on how hard you want to run your strips.

I started off running strips and COBs soft, but the guru's around here have opened my eyes to real gains that can be achieved when maintaining the environment at ~30°C vs 25°C.

I started to push my lights harder, to get more heat, but struggle with maintaining humidity - it's too dry when plants are small and too wet when they are big.

That required the installation of a humidifier and fan controller that responds to humidity.

So it also depends how serious you want to get?

If you just want to grow some plants, run some EB gen 2's at .7-.8a, shoot for 25°C and 50% RH (easy mode)

If you want to maximize yields, then consider the FB24's at 1.5-1.6a+, shoot for 30°C and 70% RH (NHL level)

OTOH, if you are growing in a basement, you will want all the heat you can get!

Edited to add;

Check out metalsupermarkets.com for aluminum

[Deece]

Hey man that sounds about right.
Like you I'm also new to the scene, and doing research for an identical build.

I say go with the HLG-480H.
Get real familiar with this page if you haven't already:
http://ledgardener.com/diy-led-strip-bu ... bridgelux/

Where I have landed so far is about exactly the Bridgelux 4x4 design:
Parts list:
12x BXEB-L1120Z 4′ Strips
1x Mean Well HLG-480H-42A Driver

Re: heat sink you will need to decide on what current you want to drive the lights at.
For these strips I've read definitively (https://www.rollitup.org/t/bridgelux-eb ... ls.957453/) that they don't need heat sinks if you run them at their rated current of 700mA. But if you want to run them at 1000mA and most definitely at 1400mA (not sure why you would though) then you'll need some form of passive heat sink.

So what I'm currently pondering is 12 strips running at 39V and 700mA so about 28W per strip or 330W. And also foregoing heat sinks all together and just screwing the strip ends to an aluminum angle square frame (thanks for the home depot link).

What do you or the group think about this? If I wanted to upgrade the fixture I could down the road add heat sink or u channel to the strips and ramp it up to 1000mA pulling somewhere closer to 470W.

I doubt the paint on the aluminum would be cause for concern, especially at lower operating current and more moderate temps. Looking at the product description in home depot it's anodized aluminum which according to Wikipedia: "Anodized coatings have a much lower thermal conductivity and coefficient of linear expansion than aluminium. As a result, the coating will crack from thermal stress if exposed to temperatures above 80 °C (353 K). The coating can crack, but it will not peel". So I think worst case is the anodization cracks (80deg is possible at higher amps) but that won't affect the integrity of the light.

Yup your plan to use u channel in place of heat sinks is consistent with the research I've done. Good plan.

Let me know how your planning goes!
Cheers!

[unkle_psycho]

I'm running 12 2-foot EB gen 2's @ 240w, so equal to 12 of the longer ones on a 480w.

The system runs really cool. Here aluminium extrusions are more expensive then strips, but I found really thin 0.6mm extrusions that are commonly used as support for gypsum elements in walls. they cost 2.20e per 3m, so I got the entire heatsinks for a 2x4 fixture for 6.60... a third of what you would normally pay for a single meter of extrusion here.

The extrusion I used is not just 0.6mm thin, but also full of 6mm holes. Once I attached the strips It started feeling rigid enough. I just used 6mm steel bars with bolts to make the frame.

[Deece]

I'm running 12 2-foot EB gen 2's @ 240w, so equal to 12 of the longer ones on a 480w.

The system runs really cool. Here aluminium extrusions are more expensive then strips, but I found really thin 0.6mm extrusions that are commonly used as support for gypsum elements in walls. they cost 2.20e per 3m, so I got the entire heatsinks for a 2x4 fixture for 6.60... a third of what you would normally pay for a single meter of extrusion here.

The extrusion I used is not just 0.6mm thin, but also full of 6mm holes. Once I attached the strips It started feeling rigid enough. I just used 6mm steel bars with bolts to make the frame.

Can you provide a link to the extrusion product you mention?

[Nuggie]

I think he is referring to aluminum perforated angle, google this and look at images

[unkle_psycho]

Yeah, also noticed a typo, i said 12 of the 2 footers are equal to 12 4 footers... half of course.

http://elbavacanze.info/wp-content/uplo ... angles.jpg

Here in Finland 20mm L bar is already over 10e/m... making anything decent is a headache.

So happy to find this cheap thin extrusion, about 0.60c /m, and works great. With the 6mm steel rod the light weighs as little as it costs.

[ocg420]

Wow, thank you everyone for some really informative responses. Just getting an opportunity to take it all in and try to understand. Maybe regretting smoking one before trying to chew on some of these replies, but here we go

@ATPinMotion - Thanks for the detailed response. I would say it's safe to say I'm going for what you're describing as easy mode, because honestly 25C and 50RH sounds pretty good based on what I know about growing right now. It's my first grow and I'm not supplementing with CO2 so I'm sure there's big room for improvement at this point. But I digress...

Maybe one day I'm going to be pushing the envelope like you, but for now what I'm really after is what I think should be about 480W of 3k flower or 3.5k full cycle light. And from the (albeit limited) amount of information I've read about how "hard" I want to drive them, I was actually leaning towards a build with more strips at 50% (or something). But anyways, definitely open to suggestions and thanks again.

@Deece Thanks for the reply. Sounds like we're on this adventure together. Saving some money on the frame and heatsink by using the cheap Home Depot options means more money for strips! Can I ask why you're aiming for 330W for the space? I read something about 30W/sq ft. so 4x4=16*30=480W. Smaller space or just looking for less light?

@unkle_psycho Full disclosure I read a few of your posts and you seem like you really know your shit! I really like the idea of two separate 240W fixtures like you're running.

Anyways boys and maybe girls, I'm going to take what you've given me and do some more research. Regrettably won't have a lot of time over next couple days but really looking forward to digging in later in the week.

Thanks again!

[unkle_psycho]

I know very little, but think aloud without much shame. I actually feel a little like a fish on dry land among the more technically savey people here, but that just reminds me how much there is to learn

I don't have too much practical ability outside speciality fields, so I took this as a way to develop my weak areas. I'm from a family of bookworms, and I got an ADHD son who will likely not end up a as much of a reader. I should be able to support him if he gets interested in some type of building.

When my kids were young I wanted to keep them of junk food. My wives family members didn't care and got them hooked since they were young. My response was to open a restaurant next to a school and spend a year on researching fast food Last year we joined a wild food competition with our icecream, and the michelin accredited chef started crying when he tasted it. Our theory was researching herbs that the chef had never tasted but that his body would recognize at a genetic level.
The whole hysteria created sent a pretty strong message to the kids. I calculated that DIY can be a similar tool that I can use to teach larger social strategy, like what solutions to search in a problem. Also any hope of generating the kids interest to any area of the real world must be explored.

[Deece]

@Deece Thanks for the reply. Sounds like we're on this adventure together. Saving some money on the frame and heatsink by using the cheap Home Depot options means more money for strips! Can I ask why you're aiming for 330W for the space? I read something about 30W/sq ft. so 4x4=16*30=480W. Smaller space or just looking for less light?

Know what man? You're right. My decision is driven by temperature, I want to keep it driven at its rated low 700mA current so as to keep it cool and reduce need for heat sinking, but I shouldnt sacrifice on overall wattage.

I've also come around to the idea of two 2x4 fixtures run on HLG-240s so I can get into my first build more affordably.

What do you think about 8 strips for 2x4 (16 for 4x4 total) instead of 6 (12 total) run at 700mA? Would pull around 220W instead of 160W. For two fixtures that would be 440W and still run cool.