Building COB LEDs. How far apart should I space them?

Hey guys, this is my first grow altogether and I am going with DIY COB LEDs that I am building. I got all the wiring done tested and ready to go but i need to go buy angled aluminum to mount the LEDs onto. I am not sure what length angled aluminum i should be using for a 7x7 flower room. Will I be okay with 4 feet long frames? Should I just divide 6 feet by 4 LEDs and just space them evenly? i dont want to waste lighting on walls is the reason i ask haha. Mainly want to make sure I dont put them too close to the walls but since i have no experience with grows not sure how close is too close.

Some info on my planned grow:
-I plan to have two seperate SCROGs in my flower room. Each one approximately 2.5 x 7 feet.
-I want to have two light fixtures (8 COB LEDs totaling 400 watts) over each SCROG).
- i also have 400 watt HPS i will probably hang VERTICALLY in the center to supplement lighting in case the LEDs are insufficient


Thanks in advance fellas!

my frames are ~41"x41" to cover a 4x4 area. i didnt wanna do too big otherwise it would be a bitch to move and store. i like the idea of doing 2x4 sections(4 per 4x8 table) just so theyre nice and easy to hang and move.

i am building mine about 12" apart center to center(1 per sq ft) but on some i am only pushing 37.5w and the others are at 50w depending on the COB/driver combo

Desert Hydro said:

my frames are ~41"x41" to cover a 4x4 area. i didnt wanna do too big otherwise it would be a bitch to move and store. i like the idea of doing 2x4 sections(4 per 4x8 table) just so theyre nice and easy to hang and move.

i am building mine about 12" apart center to center(1 per sq ft) but on some i am only pushing 37.5w and the others are at 50w depending on the COB/driver combo

Click to expand...

since im running two separate SCROGs, each one being 2.5 x 7 ft, I asked someone on reddit the same question.. they suggested I

https://www.reddit.com/r/microgrowery/comments/5uu5d2/how_far_apart_should_cob_leds_be_spaced/ said:

Make your bar 4' 7" long. Space your lights 7.75 inches from center to center. That will give you the most even coverage for that area.

Click to expand...

which basically means they suggest I line up 8 COBs in one single row. Then a couple hours later that same person replied again and said

https://www.reddit.com/r/microgrowery/comments/5uu5d2/how_far_apart_should_cob_leds_be_spaced/ said:

Now that I think about it, what might work even better is to place them in pairs side by side on the same 4' 7" bar, but spread the pairs 18 inches from each other instead of 7.75 inches. I think that would cover the outer sides more evenly compared to the center.

Click to expand...

any thoughts on these ideas? im not sure what to dooo. I appreciate your response btw thanks so much!

How are the plants arranged in each of the SCROG areas? That would give you an idea of the lighting footprint that's best suited using the # of cob's you want to use. My setup works best with two separate bars where some other room configuration might do better with a larger single array. Just depends.....

I do 12" apart at 50 watts each or 16" apart at 75 watts each. I like running about 28 watts per square foot.

Are you trying to cover 2.5 x 7 feet with 400 watts? Seems low. That's 17.5 square feet.

You can make that work though. That's fine. Did you say someone told you 18" apart? That sounds about right.

On the width you could put the 2 COBs about 12" apart. On the length space them about 18" apart.

You will love COBs! I've been building them for over 2 years now.

My space is about 26 x 50

The rig measures 12 x 48. When I upgrade I'm gonna add dimmers.
This setup uses 3500 and 4k. A very effective flowering lamp.