HElp from any and all LED heads.....

If you do go the diy/cob route, wire it so the drivers are outside the tent. They get fairly warm and are a good percentage of the total btu load of the system.

If you are really handy, build a shroud around your cobs and pull air through it just like you do with hid bulbs. There is almost no heat directed downwards (at least until light is absorbed by something and converts to either heat or sugar). Your tent will stay near ambient and you can vent right into your room.

If it helps, here are the latest KB costs for a 12 COB project I'm working on. I was looking at CXB3070-BB and CXB3590-CD with a mix of 3500K and 4000K
Here's a link to the spec's I settled on
http://rollitup.org/t/matching-drivers-and-cobs.883866/page-70#post-13278437

qballizhere said:

The vero is a good chip you just get more ppfd with the citizen or luminus with the same amount of cobs you also can run the citizen harder if you wanted.
Using the led calculator
VERO29.V2.0.4000K 9 COBS @2.1A ON 1.813 PROFILE HEATSINK
16 SQ.FT. CANOPY 93% EFFICIENT DRIVER @10 CENTS PER KWH
Total power watts at the wall: 772.04
Cobs power watts: 718
Total voltage forward: 342
Total lumens: 94848
Total PAR watts assuming 10% loss: 263
Total PPF: 1215.06
PPFD based on canopy area: 817.42
Citizen.1818C4.3000K 9 COBS @2.1A ON 1.813 PROFILE HEATSINK
16 SQ.FT. CANOPY 93% EFFICIENT DRIVER @10 CENTS PER KWH
Total power watts at the wall: 1097.85
Cobs power watts: 1021
Total voltage forward: 486
Total lumens: 140898
Total PAR watts assuming 10% loss: 387
Total PPF: 1880.82
PPFD based on canopy area: 1265.31

Click to expand...

Curious....How come I'm getting such low efficiency numbers on the citi's compared to the cree at the higher wattage...

CXB3590CD36V3500K 9 COBS @1.75A ON 1.813 PROFILE HEATSINK
16 SQ.FT. CANOPY 94% EFFICIENT DRIVER @8.5 CENTS PER KWH
Total power watts at the wall: 594.68
Cobs power watts: 559
Total voltage forward: 319
Total lumens: 91452
Total PAR watts assuming 10% loss: 266
Total PPF: 1236.9
PPFD based on canopy area: 832.12
PAR watts per sq.ft.: 16.63
Cob efficiency: 52.87%
Power watts per sq.ft.: 34.94
Voltage forward per cob: 35.49
Lumens per watt: 163.6


1212 3500K80Min 9 COBS @1675 mA ON 1.813 PROFILE HEATSINK
16 SQ.FT. CANOPY 94% EFFICIENT DRIVER @8.5 CENTS PER KWH
Total power watts at the wall: 601.18
Cobs power watts: 565.11
Total voltage forward: 337.38
Total lumens: 82989.60
Total PAR watts assuming 10% loss: 222.96
Total PPF: 1191.58
PPFD based on canopy area: 801.63
PAR watts per sq.ft.: 13.93
Cob efficiency: 43.84%
Power watts per sq.ft.: 35.32
Voltage forward per cob: 37.49
Lumens per watt: 146.86

1818 3500K80Min 9 COBS @1200 mA ON 1.813 PROFILE HEATSINK
16 SQ.FT. CANOPY 94% EFFICIENT DRIVER @8.5 CENTS PER KWH
Total power watts at the wall: 600.84
Cobs power watts: 564.79
Total voltage forward: 470.66
Total lumens: 90389.25
Total PAR watts assuming 10% loss: 242.84
Total PPF: 1297.83
PPFD based on canopy area: 873.11
PAR watts per sq.ft.: 15.18
Cob efficiency: 47.77%
Power watts per sq.ft.: 35.30
Voltage forward per cob: 52.30
Lumens per watt: 160.04

So it seems to me, best bet to stick with the 3590's (efficiency) if I plan on running them at a combined total wall draw of 450w-600w?

Or the 1818 citi's for the discounted price?

I thought there were some more efficient chips out there than the crees now at 60-65 wall watts

This whole thread if anything made me realize something.........reading this thread the things you guys dissuss about lsd's and cree this ...chip that things that were never available to me ....not knowing a fraction of what you guys are talking about I guess I'm an old school grower cause I don't think I'm ready to wrap my head around all of this shit.....I ordered 3 Apollo 4 Advanced 180w Led's if I can't push 2-3 decent plants with those it back to hid or maybe lec

Don't be discouraged. This is new technology and some of us grasp it faster than others.. Some of us are builders, some engineers, and some of us think we're gods.... But we're all here to learn..

I'm in the process right now of learning how to start my own thread and i've been lurking around here for 6 years. hahahahahahah

Godfather420 said:

Don't be discouraged. This is new technology and some of us grasp it faster than others.. Some of us are builders, some engineers, and some of us think we're gods.... But we're all here to learn..

Click to expand...

I just like DIY. I understand wiring and the basics needed for picking drivers and some other hardware. Not completely though. In fact, my build is probably fair from the best, but it will finish my plants. That is all I care about.

I plan on building a much larger tent so I can fully SCROG 4 plants with room to walk around. I'm mostly learning by experimentation on my current setup.

You and me brother.. And i like to be helpful.. I've learned everything I know from somebody smarter than me. I'm just about to start my water-cooling thread on my light build. you have to stop by and check it.

I'm gonna be replacing 16 600w bps's with all cobs. ; )

Godfather420 said:

You and me brother.. And i like to be helpful.. I've learned everything I know from somebody smarter than me. I'm just about to start my water-cooling thread on my light build. you have to stop by and check it.

Click to expand...

Watercolor cobs? I like. The build I do in the big room I plan on mounting to a diy rotating fixture. Still haven't figured out how I'm going to wire it.

Check out Kessil... I believe they just released something like that. I'll see if I can find it.....

That might give you some ideas

Johnnygrows420 said:

This whole thread if anything made me realize something.........reading this thread the things you guys dissuss about lsd's and cree this ...chip that things that were never available to me ....not knowing a fraction of what you guys are talking about I guess I'm an old school grower cause I don't think I'm ready to wrap my head around all of this shit.....I ordered 3 Apollo 4 Advanced 180w Led's if I can't push 2-3 decent plants with those it back to hid or maybe lec

Click to expand...

If it makes you feel any better, I spent the last month or so reading, knocking the cobwebs off stuff I learned 50 years ago, and figuring out what I wanted to do to start growing. For a really good intro to DIY LED topics, you should really check out Growmau5's videos 1-7 on the topic


You may still decide to buy ready made but you'll have a much better understanding of what's going on.

I decided on a 48 x 48 x 80 for a first tent, and if I manage not to kill everything I plant and actually bring in a respectable harvest I plan on using if for a veg tent and putting in a 48 x 96 x 80 for flower.

I was originally going to just buy equipment, but it turns out almost nothing under $1,200 - $1,500 is actually spec'd for flower in a 4 x 4. Most configurations under that price range are only suitable for 3x3 if you read the fine print. And so it began. After looking at the price tag on commercial units that would give me the light intensity and coverage I wanted, my wallet told me it was a no brainer to build my own. To get these specs at max intensity, with the ability to dim down to a gentle glow for young plants would have cost me close to double. I think the specs are actually a little better since I've mixed on a few 4000K COBs for better blue spectrum, but this is pretty close.
And dimmed down, I'll only be drawing about 300W at the wall with a PPFD of about 500 at the canopy.

CXB3590CD36V3500K 12 COBS @1.4A
16 SQ.FT. CANOPY 95% EFFICIENT DRIVER
Total power watts at the wall: 616.84
Cobs power watts: 586
Total voltage forward: 419
Total lumens: 106968
Total PAR watts assuming 10% loss: 297
Total PPF: 1381.05
PPFD based on canopy area: 929.09
PAR watts per sq.ft.: 18.56
Cob efficiency: 56.34%
Power watts per sq.ft.: 36.63
Voltage forward per cob: 34.89
Lumens per watt: 182.54
Total heat watts: 256
umol/s/W / CRI: 4.65 / Estimated

This may all seem like I'm speaking in tongues, but my take on it is that if I'm going plunk down over a grand on something, I'm damn sure going to try to get my money's worth (see .... I'm old school too)

Whatever you decide, best of luck.

meangreengrowinmachine said:

I have watched all growmau5 vids and looked a lot at sourcing my own stuff... I have said this on many threads (I swear I don't work for these guys lol) Timber grow lights seems like a very easy and configurable way to go.. not the cheapest but very reasonable when looking at ordering all parts diy

Click to expand...

I feel the same way I am going to get the 5x5 Vero framework soon, now I can't decide to go 3k or split between 3k as Nd 3.5

atomicDETH said:

I feel the same way I am going to get the 5x5 Vero framework soon, now I can't decide to go 3k or split between 3k as Nd 3.5

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I'm in love with my vivosun tent. I really want the 5x5. I have heard others are better, but if the quality in the larger tent is as good as my 2x4, I see no reason to spend an extra $100-200 on a more expensive brand.

That is the tent I plan on expanding into. I wanted the rotating lightso so I can do a "less is more" build with more spectrums providing full coverage light for less watts at the wall.

I don't know if that's realistic though. I have yet to read up on it.


EDIT: The Kessel is the reason I want to diy my own rotational light. As I said, I like to build most stuff. The more I spend on this "hobby", the more I find it is almost always better to diy.

NapalmZen said:

I'm in love with my vivosun tent. I really want the 5x5. I have heard others are better, but if the quality in the larger tent is as good as my 2x4, I see no reason to spend an extra $100-200 on a more expensive brand.

That is the tent I plan on expanding into. I wanted the rotating lightso so I can do a "less is more" build with more spectrums providing full coverage light for less watts at the wall.

I don't know if that's realistic though. I have yet to read up on it.


EDIT: The Kessel is the reason I want to diy my own rotational light. As I said, I like to build most stuff. The more I spend on this "hobby", the more I find it is almost always better to diy.

Click to expand...

Diy'ing anything has its pro's and con's.. Better product yes, but i always find i spend more....as you can see in my water-cooled thread, when cost ain't an option, things add up. But like you said napalm, i wouldn't do it any other way! DIY 4 life

Johnnygrows420 said:

Hey peps....soo long story short I lost my grow room due to a move so where I'm at now I have tto use a tent that has to stay zippered so there's no way I'm gunna be running g my 600 w hid without major heat stress even with my 34e cfm exhaust I don't have a cool tube just a batwing.......so I have a 4x4x7 tent I'm not a believer in LED mainly because I never used them and they are just outrageous in price. But if you were in my shoes and had to buy and USA a LED LIGHT and you only had 300-350 to spend what would you buy? Or should I just not even try? And if something will work for my price range.....I'm just using this as an example but would a guy be better off using two 300 watt fixtures or one 600w......or one 1200 or two 600w I'm sure you get my point. Any info would be greatly appreciated

Click to expand...

COB is the only way to go for LEDs.

Godfather420 said:

Diy'ing anything has its pro's and con's.. Better product yes, but i always find i spend more....as you can see in my water-cooled thread, when cost ain't an option, things add up. But like you said napalm, i wouldn't do it any other way! DIY 4 life

Click to expand...

Yes and no. My diy cob lights cost 220-250 for a setup that would cost around 300-450 from timber.