DIY LED with COBs - small medium and large grows

[REALSTYLES]

Hi all, I'm a french guy and I have some difficulties to understand all you said. I didn't find information on French sites so as I'm brave and even my English is poor, I'm asking for advices. I want to cover 4ft x 4ft only with COBs and if I understand I need 50w per sqft. So I must install 16 COBs! Oh sh**, I don't have enough money! My questions are: Can I do with only 9 COB? Do I prefere 3070 or 3590 for the COBs? And for the driver I don't understand "efficiency". When you want calculate how many watts are used finally, do you use this formula : P=UxI? Anyway I need your advices to grow the best French DIY! :) Thanks in advance for your help! And very thanks to all information already given here!

There is a guy named littlejacob on rollitup he lives in France look him up and tell him I sent you and he will help you for I've helped him

 

[Greenbyme]

Hi, I saw that. I haven't understand all about efficiency but anyway I took a configuration from Sspl (with meanwell driver 185 and cxb3590). Now I m ready to build my own led light with 8 cxb3590 3500k and 2 cxb3590 5000k (thanks Jerry). I receive my drivers from Elpro (Germany) tomorrow, impossible from kingbrite (delivery too expensive). The next time I plan to use passive cooling because it's very difficult build with arctic 64. I broke 3 drill at this time . And I try to fix them at sheet of steel (no aluminum)! Anyway its my first build! Many thanks to teach me. Cheers

 

[Dabominable]

I wish i was more savvy so i could build some shit like this. Respect man. Maybe i need to pick this up as a hobby and try and figure it out. I always wanted to do a like 4ftx4ft or 4x6 panel. This is some amazing work, knowledge, and detail. Again, thanks man

 

[seaslug]

The COB tech has made things much easier than messing around with individual diodes.

I don't recommend it but . . . a guy built a high powered light (on another site) and he had to learn how to use a digital multimeter before he could troubleshoot his light. He eventually got things to work and now he knows some stuff.

 

[SupraSPL]

3 Watts, total, seems way low, even for LEDs, even just for clones.

Give it a shot, I think you would be amazed. 3W of LED is plenty for a cloning box.

 

[Dabominable]

Give it a shot, I think you would be amazed. 3W of LED is plenty for a cloning box.

You can root clones without light too, so a minimal amount of light will work just fine

 

[Tejashidrow]

Today is Christmas
I am doing the 12 inch with 2 one hundred watt Cree Cob
Last week got my thermal paste, heat sink from heat sink USA,,,
Fan, and wire, and drivers
Unfortunately I got 18/2 SOLID alarm wire.
So gotta hit some 50% sales nest week to pick up some 18/2 speaker wire.
Still waiting on the cobs.
Also contemplating picking up a couple 100 watt full spectrum China cobs off eBay just to play with.
The price is good enough I can replace them yearly
Can't wait for the rest to arrive so I can get this build going!!!

 

[Dabominable]

gonna be keeping my eye on this! Hope to learn some stuff from watching you! Merry xmas cree-man ;p

 

[Dabominable]

Toaster - thank you for the suggestion on the Meanwell driver, I will check it out.

I re-posted the pictures as jpegs. The entire housing acts as a heat sink. I misspoke, it's actually a channel - not a pocket. The photo shows an extrusion with black anodize, but we have a lot of this stock that is simple silver (mill finish - no anodize). I am using a thermal adhesive paste, so the flat stock for the spacer is plenty flat enough as the paste fills in any gaps. I agree that it would be slightly preferable to have the channel shallow enough to not need the spacer plate, but as mentioned it was designed originally to be an LED light bar housing. The spacer is easy, just takes 5 minutes for the thermal adhesive to dry, I have the standoff pieces and can provide the spacer plate with the standoffs already attached. I could attach the spacer plate w/standoffs to the to the The other nice thing is that it has t-slots on the top, so (4) t-nuts can be used with eye-bolts to hang it, I have those too. The housing extrusion comes from the factory cut at 12' long, so I can have them cut to any length shorter than that. so if someone want a 48" or 60" light bar no problem

View attachment 519901 View attachment 519904

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Curious what you'd charge to build a 4-5ft light bar, one for veg. Do you know what the footprint is on it? i need to upgrade my old t8 leds, trying to get 5-6ft of growth in 2 months between bringing them out for sun and back under lights. With my leds, i know its a pretty far off sight. I was just about ready to take an old xtrasun switchable 400/600/1k ballast down to the shop to get it fixed, and get a big parabolic hood, and run a MH. But with what i've read in this thread, with the right spectrum and the right lights and equipment, you get the best results with these lights vegging, and don't break the watt bank too hard? If you can figure out the foot print on4-5ft one, and the total cost you'd charge, and maybe total watt/lumens per..i'm pretty sure i'd buy 3-5 of these rather quickly if it can match an hps/mh for 1/3 the cost (or near)

 

[Dabominable]

Also, from other people's experience, what sort of setup gives you the best vegging "linear" footprint? I'm undecided if i should do a 4x12 general area for veg, or like a 7x7 type deal. What sort of wattage draws can you get away with? prefferred spectrum or mix? What sort of growth rates? Would it be silly to consider doing like 10-20 single leds placed over/around an area i've made? All knowledge appreciated

 

[WitchWeedSG]

Also, from other people's experience, what sort of setup gives you the best vegging "linear" footprint? I'm undecided if i should do a 4x12 general area for veg, or like a 7x7 type deal. What sort of wattage draws can you get away with? prefferred spectrum or mix? What sort of growth rates? Would it be silly to consider doing like 10-20 single leds placed over/around an area i've made? All knowledge appreciated

you should re read the thread :)

 

[Dabominable]

I recall reading one of those cobs had a 2x2 foot print for each one of the 100w cobs? I also get that it's not a cheaper alternative to an led light, but a better more effective one, if not more expensive. I'm just wondering what would be easier layout for both DIYing my led light, and the area i've got to work with. I also read about the full spectrum chips. For vegging would i be better off with 5k or 65k or full spectrum for veg? Its been a few years since i read into anything new in the led DIY world, so sorry if i miscommunicated what i was wondering..

 

[Tejashidrow]

Hey all
Starting my build
This may be a silly question but.....
I am going to be useing 2 cree 3070 cobs
On a 1 foot heatsink.
So-
Getting ready to mount my fan.
Which direction should the fan go??
Blowing down on the heatsink or blowing up from the heatsink???
Thanks

 

[WitchWeedSG]

Hey all
Starting my build
This may be a silly question but.....
I am going to be useing 2 cree 3070 cobs
On a 1 foot heatsink.
So-
Getting ready to mount my fan.
Which direction should the fan go??
Blowing down on the heatsink or blowing up from the heatsink???
Thanks

down into it

 

[WitchWeedSG]

I recall reading one of those cobs had a 2x2 foot print for each one of the 100w cobs? I also get that it's not a cheaper alternative to an led light, but a better more effective one, if not more expensive. I'm just wondering what would be easier layout for both DIYing my led light, and the area i've got to work with. I also read about the full spectrum chips. For vegging would i be better off with 5k or 65k or full spectrum for veg? Its been a few years since i read into anything new in the led DIY world, so sorry if i miscommunicated what i was wondering..

3500k seeds to flower,

 

[Dabominable]

Okay, cool. Thanks

 

[Tejashidrow]

@SupraSPL
looking at your 12 inch heatsink usa cob build pictured i have a couple questions.
in your pic i see a wire going to the fan, 4 wires on front edge and ( i assume??) 4 wires on the back edge.
total nine wires.
on mine i have 2 wires per cob=4 wires.
and one wire for fan.
Total 5 wires.
What am I missing???
Is there a way to get a picture from the bottom view (lights off) of your 12 in her??
Thanks

 

[Seamaiden]

I haven't been through this whole thread, I perused the first post and decided this would be a good sticky for the forum. Any objections? Any other suggestions for threads that should be stuck to the top of the forum here?

 

[str8smokn]

So not much for building one yet but how do these look ,I know there's not much info here but maybe I can find some.

STR8

 

[str8smokn]

What would the output be on these?
STR8