My Cree CXB3590 grow light setup

Started out with one bar that had 4xCXB3590s, 36V, 3500K, CD bin on a Meanwell 240W 1750mA driver. That light was nice but it restricted my growing area somewhat to 1.20x0.60m (4x2'). That light bar, including the lenses and shipping the COBs from Kingbrite cost me about €400.
 
However, I got really tired of the restricted growing space since I wasn't able to use my greenhouse to the fullest.
 
So yesterday I was finally able to modify my light from the one bar with 4x COBs to two bars which 3x COBs each, the two bars are connected in parallel to the same driver. With the driver fully turned up, since the two bars are connected parallel it should deliver 875mA to each COB which is a sweet spot for CREEs. The lower you drive them the more lms/Watt. According to cheap and dirty calculations, the entire fixture should put out about 390ish PPFD for my growing area which is now 1.20x1.10m (4x3'). It is so much better than the one single heatsink.
 
Modifying my light was a monstrous work and total pain in the ass, especially the drilling of holes in the old bar to move one COB to the middle. The larger 4mm holes were less of a problem but for some reason the 2.3mm were, I must have broken like 5 drill bits. The other 90cm bar I had-predrilled, but the holes for the fans were placed poorly, right under the silicone for the lenses. So I had to find a way to mount the fans. Found that ONE screw is actually sufficient to hold the fans in place.
 
As for the lenses, from what I see I actually like the plain COBs for their spread, but I will still get two more lenses mainly for protection.
 
Don't mind my ugly Jalapenos and Serranos, I cut them some days ago because they grew to very tall monsters, I made the newbie mistake not having topped them early enough. So right now they look plain and ugly, but new branches are coming fast.
 
My grow setup is a "Hempy Bucket" setup where I grow in perlite/vermiculite with a small reservoir, aluminum foil pans, at the bottom of my pots. I am using GH MaxiBloom 1.5ml/l as my nutrient. Grow rate and speed are just insane with this setup.
 
Light isn't exactly a beauty but who cares I placed the fixtures that way to have some open room in the middle of the greenhouse for watering etc., rather than sideways (like I had before), but I don't think it matters much how I hang them.
 

 

Set up looks good. I really don't want to use lens's, but probably will just for protection.

Cheezus did I really have 14 plants in there last year?
 
I don't remember whether it was this grow from the picture or another...but it was way too many plants for my greenhouse..which led that one of my last harvests basically all plants were infected with powdery mildew. Really, really bad, at the end at about harvest they dropped all leaves. 
 
(Less plants = better airflow...). I might also have way too late realized that I had a problem (mites, mildew etc.) so I started spraying when it was already too late and the plants had already been infected.
 
Anyway...new grow...eight plants now the absolute max. I am growing Purple Jalapenos now, light is further down and I also turned up  light intensity on the dimmer.
 
I also ditched my Hempy/Hydro (Perlite/Vermiculite), it started to annoy me or I just got bored with it.
 
Growing in un-fertilized grow mix now (Pro-Mix) w/ just a little Perlite mixed in, same nutrients. (Floranova Bloom - that stuff is incredible!)
 
Grow INCREDIBLY fast, it was just a few weeks or so I actually planted them...they are fruiting now!!
 
Also..the plants are now growing the perfect size, not so incredibly tall like my last grow which grew hideously slender, lanky plants which I must have cut three times.
This time, PERFECT.
 
I think it's the combo smaller pots (using only 3L pots!), using Pro-Mix instead of Hempy buckets, slightly lower outside temps, and the light more intensive that the plants don't grow as slender now. Can't wait. I found Purple Jalapenos having the best balance of taste and "a tad" spiciness, unlike Seranos which I grew where SOME of them were just too hot for me. (But they made the perfect chilly powder!)
 
As for the lenses: Yes started to annoy me as well. Incredibly pain in the ass to remove them to clean then, once every few months, since some are placed that way I need to remove the fans first to be able to get to the screws. And without lenses, things are actually fine. I like the wider spread. And when the COB chips get somewhat dusty in time it's easy to just wipe them.
 

flexy123 said:

Cheezus did I really have 14 plants in there last year?
 
I don't remember whether it was this grow from the picture or another...but it was way too many plants for my greenhouse..which led that one of my last harvests basically all plants were infected with powdery mildew. Really, really bad, at the end at about harvest they dropped all leaves. 
 
(Less plants = better airflow...). I might also have way too late realized that I had a problem (mites, mildew etc.) so I started spraying when it was already too late and the plants had already been infected.
 
Anyway...new grow...eight plants now the absolute max. I am growing Purple Jalapenos now, light is further down and I also turned up  light intensity on the dimmer.
 
I also ditched my Hempy/Hydro (Perlite/Vermiculite), it started to annoy me or I just got bored with it.
 
Growing in un-fertilized grow mix now (Pro-Mix) w/ just a little Perlite mixed in, same nutrients. (Floranova Bloom - that stuff is incredible!)
 
Grow INCREDIBLY fast, it was just a few weeks or so I actually planted them...they are fruiting now!!
 
Also..the plants are now growing the perfect size, not so incredibly tall like my last grow which grew hideously slender, lanky plants which I must have cut three times.
This time, PERFECT.
 
I think it's the combo smaller pots (using only 3L pots!), using Pro-Mix instead of Hempy buckets, slightly lower outside temps, and the light more intensive that the plants don't grow as slender now. Can't wait. I found Purple Jalapenos having the best balance of taste and "a tad" spiciness, unlike Seranos which I grew where SOME of them were just too hot for me. (But they made the perfect chilly powder!)
 
As for the lenses: Yes started to annoy me as well. Incredibly pain in the ass to remove them to clean then, once every few months, since some are placed that way I need to remove the fans first to be able to get to the screws. And without lenses, things are actually fine. I like the wider spread. And when the COB chips get somewhat dusty in time it's easy to just wipe them.
 

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Glad to hear you've got it tuned up. I used my cobs for just starting seeds. The older plants had no problem putting out pods. I may use it agin this Fall for overwinter. Just depends on if I got room. The downside for using them in the Winter is no heat vs a HID. I like them better than the HIDs.

Congrats!