DIY LED with COBs - small medium and large grows

[sixstring]

cobs work awesome :cool:

 

[SkylineSeeds]

cobs work awesome :cool:

Do they have comparable yields over the same floor space as hps?

 

[sixstring]

Better

 

[SkylineSeeds]

Better

So if I wanted to replace 2 1000w bulbs I would need like 32 cobs spaced 1 foot apart? Seems most run them at half power so that's 800 watts at the wall to cover 8x4?

 

[sixstring]

well if you really want to match your 2000w hps you should shoot for more than 800w of cobs.i would say 1200 to 1400w of cobs would match or beat your current setup.how do you grow,like how tall are your plants?

 

[SkylineSeeds]

well if you really want to match your 2000w hps you should shoot for more than 800w of cobs.i would say 1200 to 1400w of cobs would match or beat your current setup.how do you grow,like how tall are your plants?

I usually run about 12 plants in an 8x4 4-5 ft tall. Soiless dtw.

 

[sixstring]

well theres lots of ways to do it,just need to pick a cob and driver and build it,or buy some pre made fixtures.i would do like 12 cobs per 4 x 4 run off meanwell drivers at 1750ma for taller plants like you mentioned.using cree 36 v cobs you would end up around 1512 watts but could dim to 1200 or 1300w and still kill it.even using 1400ma drivers would be plenty bright in that space.theres kits out there,makes it pretty easy to diy

 

[hdrhyder]

Hey guys a lot of you know me from RIU or ICMag but for the LED growers here that have not seen it, here is the recipe for building DIY LED very cheaply. Why build a DIY lamp? You can get up to 49% efficiency if you can find the top bins and run them soft (700mA). You can get 36% efficiency with the mid bin running hard (1400mA). The best commercial LEDs (Area 51, Apache, Onyx) are in the low 30s. Another advantage is the ability to have remote drivers to keep that heat out of your grow space and away from the LED heatsinks.

Everything has changed since COBs became available to us. It is much easier to build a lamp and it turns out that 3000K works just fine on its own, better than HPS even.

For the simplest build the best COBS to use are the Cree CXA3070 and Vero 29. The CXA 3000K has 14% blue and the Vero 3000K 8-10%. They are available on Digikey or if you need a bulk order you can save $ on Arrow.

As far as drivers go, 1.4A is a good compromise between cost and efficiency. They are available on eBay for $13, 90% efficient and power factor corrected. You can use Mean Well LPC-60-1400 but it is lower efficiency and not power factor corrected. If you want to run at 1050mA you can use Mean Well LPC-60-1050. The one I tested was 88% efficient.

For heatsinks, CPU coolers work great for small grows. The 92mm Arctic 11 Plus is a favorite because it can be found for $10 and uses a fluid dynamic bearing fan, lots of cooling power and not too loud. Amazon and Newegg sometimes offer them for $10. Currently outletPC has them for $10 with reasonable shipping cost.

If you are building a medium or large lamp, I recommend HeatsinkUSA 5.88" profile. A 12" length is good for (2) COBs and a 24" length is good for (4) COBs. You can cool it with a single 140mm fan to make a super efficient cooling combo. I recommend the Prolimatech 140mm from Amazon. It is quiet even at 13V and moves a lot of air.

View attachment 415611

The Vero is solder free but the Cree requires a COB holder and to go solder free. Both methods require drilling and tapping the heatsink. I don't mind the soldering so rather than drilling, I mount the COB with Prolimatech PK3 thermal paste and then use kapton to tape the COB in place so it cannot slide sideways. The paste makes a very strong vacuum when you press the COB onto the heatsink. It will not come off from gravity or heat. If you try to pry it off it will break. You have to twist it and then slide it sideways to get it off.

Small build:
View attachment 415595

Medium build:
View attachment 415593

Large build:
View attachment 415594

 

[hdrhyder]

any one looked at arrow.com for cxb s best price I can find & free shipping ....supra you lined me out on led s

 

[Mraoa]

lets say to build a DIY led equivalent to lets say..... a 1000w hps, what would the estimated price be in parts

 

[hdrhyder]

If you want a accurate answer ask Supra ...I shoot for 40w sq ft but so many variables in drivers , heat sinks etc. ..first up read this thread , look at what others have built , think of your personalization or just copy their build ...again Supra is the doctor on site I'm in the middle of my first build & not up for advising like any authority I am a shopper & Arrow was by far the cheapest w free shipping to

 

[robomont]

40 watts per sq ft.?
i thought it was 25 -30.is 25-30 for just hps

 

[hdrhyder]

40 watts per sq ft.?
i thought it was 25 -30.is 25-30 for just hps

thru this thread I'v read 25 - 50 W per sq ft I'm at 600W on 16 sq ft so 37.5 w per sq ft over hp aeroponic w scrog as I said I'm on my first build you are obviously far more knowledgeable than myself advise Mraoa of cost to replace his hps lighting w led ...hps w per sq ft? on the diy led thread? I'm lost again ....anybody got anything good or helpful to say ? only reason I joined this thread was to share best pricing on top grade cobs & the response I get is a smart.... AWESOME ....GONE!!!!!!

 

[sixstring]

Lol every grow is different. Take a big poke from the bong and chill n read.this thread is 2 years old,lots of changes since it started yet so much valuable info in the first few posts.1 cob per sq ft @ 35 to 50w is a very good setup.yes you can run 1 cob per 2 sq ft and bump up the wattage to say 64 to 75w and still rock the hizzy.diy prices can be all over the place depending on the parts you choose,cree cobs are pricey but worth it imo.lots of other great options now like vero and shitizen that perform and are cheaper.same with drivers,same with heatsinks.we have lots of options on round pin style sinks now.knockoff drivers can be almost half the price,i prefer meanwells.doesnt mean you cant build a better light than me using cheap cobs and drivers.but you need to know what you want out of your grow space.
Pre built fixtures are the same,really good shit from plc and northern grow will be about 2 or 3 bucks per watt,lots of other led panels for 3 to 5 bucks per watt that wont touch the first 2 in quality of light and parts used.
Read read read.

 

[hdrhyder]

Lol every grow is different. Take a big poke from the bong and chill n read.this thread is 2 years old,lots of changes since it started yet so much valuable info in the first few posts.1 cob per sq ft @ 35 to 50w is a very good setup.yes you can run 1 cob per 2 sq ft and bump up the wattage to say 64 to 75w and still rock the hizzy.diy prices can be all over the place depending on the parts you choose,cree cobs are pricey but worth it imo.lots of other great options now like vero and shitizen that perform and are cheaper.same with drivers,same with heatsinks.we have lots of options on round pin style sinks now.knockoff drivers can be almost half the price,i prefer meanwells.doesnt mean you cant build a better light than me using cheap cobs and drivers.but you need to know what you want out of your grow space.
Pre built fixtures are the same,really good shit from plc and northern grow will be about 2 or 3 bucks per watt,lots of other led panels for 3 to 5 bucks per watt that wont touch the first 2 in quality of light and parts used.
Read read read.

Hey Sixstring.. did that ..well said ...will post my build when its up & running , I'm using Geitan 84.5w 26 -2900k cobs at 6500k they advertise 170lm p w but are 130 at the lower kelvin I am also running cxb3070 cree's syde by side to compare they are identical in size , any idea how many chips are on a cxb3070? the Geitan's have 324 I'm dealing with the factory directly ...wish I knew more about light testing i.e. lumens , spectrum , umol,etc. but I'm old fashioned like "how green does your garden grow?" Peace

 

[sixstring]

i know nothing on those 3070,never had one in my hands.but i have seen the data sheets on em and lots of good grows with them.im curious to see your geitan build and grow,tag me in if you log it here.

 

[hdrhyder]

I'm finishing a grow with commercial built chinese cob grow light s its so hard to say whats what when you get a 1800w light that pulls less than 400 watts??? so the build ,the people at geitan are very proud of their product and spec them well over anything cree shows soooo the side by side ...would be interested in comparative parameters if any have input other than brand loyalty ...looking at light meters

 

[hdrhyder]

i know nothing on those 3070,never had one in my hands.but i have seen the data sheets on em and lots of good grows with them.im curious to see your geitan build and grow,tag me in if you log it here.

Lordy Brother you got the strain & flower thing happening!!! like I'm lickin the screen DAMN ...I quit carryin buckets of dirt a couple of years ago & have been soilless ...different can of worms , landed on high press aero got the dirt cheap setup working flawlessly{ pun intended} there is virtually nothing on nutes for aero , timing , cost , ppm , ec , etc. lotsa BS by people who do not nor ever did have the setup ...this grow is lemon kush I'll see if I can get pics posted looking like a lb of dry bud...using regular lights its impossible to get even light distribution I put a lux app on my galaxy & found out how bad it is ....we be fixin shortly ....the nutes have been a problem ...going the simplest I can on this grow GH Maxibloom w no amendments thru the entire grow not to exceed 600 ppm at the mid bloom this goes w Mel Franks 100 , 100 , 200 npk for cannabis ....I have a overfeeding problem ...more is better right? Peace Brother

 

[ofbyah]

Here is a question for the ones that know more than ....
I built a little setup to put in the kitchen window for spices...really
3 x cree CXB3590 CD 36V
silicone lens 90 degree
Meanwell driver HLG-120H-C1400B
dimmer

all from Jerry at Kingbrite - I cannot recommend him enough to anyone interested

The math
36v x 1.4 A = 50.4 watts per cob, 3 cobs should mean 151.2 watts of light

My Kill-A-Watt meter says I'm consuming 60 watts
seems like a great deal
What am I missing?

 

[Toaster79]

Here is a question for the ones that know more than ....
I built a little setup to put in the kitchen window for spices...really
3 x cree CXB3590 CD 36V
silicone lens 90 degree
Meanwell driver HLG-120H-C1400B
dimmer

all from Jerry at Kingbrite - I cannot recommend him enough to anyone interested

The math
36v x 1.4 A = 50.4 watts per cob, 3 cobs should mean 151.2 watts of light

My Kill-A-Watt meter says I'm consuming 60 watts
seems like a great deal
What am I missing?

How did you wire your cobs?