DIYers try to recreate CREE vs Gravita?

I'm newly back to growing after a 3 year hiatus. As we begin to set up our room, mu husband and I are seriously considering doing a DIY led lamp for our new flower tent.

It seems like COBs are the current mainstay amongst the group. Has anyone tried to make a diy lamp like the one Cree used to compare themselves to a Gravita HPS? What are the advantages/disadvantages over COBs?

I am going back and forth between recreating one of Growmau5's cob designs, and trying to do a very DIY of a spydr styled light with crees recommended diodes.

http://www.cree.com/~/media/Files/Cree/LED-Components-and-Modules/XLamp/XLamp-Reference-Designs/HorticultureReferenceDesign.pdf?la=en

This will be my first LED light, but I come from a math/science background....so I do not believe that (with studies) either build would be too much for me. I don't want to go fancy with my first light, and I do think I would like to passively cool it.....but we will probably do one run with the old hps while designing and building this new light.

BTW, this build would be to replace a 600 hortilux bulb in a dimmable Phantom ballast, etc. The tent we used to use was dry rotted after our last run, so we are replacing it with a 4x4 for flower, and I have a closet that we are setting up with a Martha bloom chamber for mushrooms and a total of about 10-12 sq ft of veg space.

No additional CO2 will be added at this time, but I will be getting at least 1 carbon filter and in line fan to reduce smell. As well as the old 4" 200 cfm fan from our previous build circulating air out of the grow area for heat dissipation.

We had thought about just running 1000 w hps in our current set up, but I don't know if our home A/C could keep up this summer and (for stealth reasons) an additional unit is not an option.

You really cant go wrong with one of Growmau5's lights and for ease of assembly COBs are the bees knees. Everyone seems to be in a lather over the Quantum boards at the moment but there is always something new.

As a first DIY, I would definitely go for COBs because your first DIY will not be your last. It is instantly addictive.

I built 2- 4 COB light fixtures with cree Far Red, InfraRed, Deep Red, and royal Blue. I used 4 cxb3590 3500K for flower with the reds and 4 cxb3590 5000k with the Blues. I designed and built a led light controller to make both custom lights timed correctly. it is called the GrowGreen led Controller for building custom led lights with multiple spectrum. with 6-8 channels you can add all your different crees colors and schedule them for veg or bloom.

I think the custom light with cree supplemental 3w/5w led and COB's is the best of both you get the color spectrum needed and power too. I love the idea of building a light better than the commercial market. My lights produce well developed veg activities and excellent flower response. of course growing style effects the outcome as well as lighting.

I say go for it. There is another thread about the same light build.

I bought gavita 2 yrs ago and get almost 3 lbs a light and I didn't have to build anything

AliCakes said:

It seems like COBs are the current mainstay amongst the group. Has anyone tried to make a diy lamp like the one Cree used to compare themselves to a Gravita HPS? What are the advantages/disadvantages over COBs?

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dont expect to replace a gavita with 550W like they claim. 700-800 W of LED is more realistic

I would recommend using these MCPCBs instead if you do decide to go with it. They do make them in strips as well but you would have to reconfigure it slightly because I don't think they have the 2x6 strip that this build uses.
The MR16's have lenses that are much cheaper as well.
http://led-mounting-bases.com/en/led-mcpcb/16807-mcpcb-diametre-40mm-pour-7-led-cree-xp-g3-compatible-optiques-ledil.html

Personally would use COBs instead of the XP-G3s and then supplement with the 660nm, far red and royal blues if you desire to decrease cost The build is not as DIY friendly as it seems but gets you in the right direction. Very expensive components including the pcbs, heatsinks and framing.

Hard to beat the quantum boards for ease of assembly and price.

Were I to start again I'd build four 22" x 22" squares of 22" samsung hard strips.

CobKits said:

dont expect to replace a gavita with 550W like they claim. 700-800 W of LED is more realistic

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Not if you go by PPFD, also depends on how many in the matrix. If it's 1 vs 1 then you should only need 800ppfd in a 4x4 to beat it out, what ever that works out to in watts depends on your budget

so, not much savings in watts and you may need to add supplemental lighting and you have to build it yourself, or just hang a light and grow dank.

There are two ways to do a comparison. You could build a 1000w cob lamp that will beat the pants off a Gavita, or you would build a lamp with 1700 PPF, same output but with a different spectrum and light distribution. I think matching the quantum output would be the more interesting and useful comparison.

another option you could consider is the bridgelux EB series http://www.digikey.com/products/en/optoelectronics/led-lighting-cobs-engines-modules/111?k=&pkeyword=&pv1614=345&pv319=1393&FV=ffecd831,fffc03d0&mnonly=0&newproducts=0&ColumnSort=0&page=1&quantity=0&ptm=0&fid=0&pageSize=25 these can be operated at up to 700ma without heatsinks. 18 strips at 700ma would give the same PPF as that cree test light. you could supplement with cree photo reds and even a UV tube ( like california light work uses in their LED grow light) to increase THC and CBD production

Rahz said:

There are two ways to do a comparison. You could build a 1000w cob lamp that will beat the pants off a Gavita, or you would build a lamp with 1700 PPF, same output but with a different spectrum and light distribution. I think matching the quantum output would be the more interesting and useful comparison.

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with natural sunlight photo inhibition occurs at 750 PPF. why would you want to run 1700 PPF. seems like a lot of wasted light. same claim LED grow light makers make about HPS. monos are becoming very effiecient. seems like getting closer to natural sunlight may be a better option . high end LED grow light makers like black dog, california light work, platinum and others seem to be taking this approach using up to 12 bands of monos ? I have been growing with T5s for years but enjoy experimenting with LEDs as well.their just seems to be many conflicting views on the best type of grow light ( multi-band VS white).

mauricem00 said:

with natural sunlight photo inhibition occurs at 750 PPF. why would you want to run 1700 PPF. seems like a lot of wasted light. same claim LED grow light makers make about HPS. monos are becoming very effiecient. seems like getting closer to natural sunlight may be a better option

high end LED grow light makers like black dog

, california light work, platinum and others seem to be taking this approach using up to 12 bands of monos ? I have been growing with T5s for years but enjoy experimenting with LEDs as well.their just seems to be many conflicting views on the best type of grow light ( multi-band VS white).

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You said high quality light, Blackdog, and platinum in the same sentence.. Please don't. Not good lights.. Not sure about clw yet but there's a grow going now running them.

As for why you would hit 1700ppfd... To get the most yield out of a given area and adding co2. I plan to do just that in my next lighting addition. Having around 11ppf/W and 900W in a 4x4 running 48 cobs. The point being that I ran my cobs within 3-6 inches from top colas with no bleaching. The bid was massive and the PPF in that spot was well over 2000. Not saying all the light was used but the plant didn't seem to mind.

Co2 next run.

@AliCakes, by now you've probably read through some of the LED threads and know that there are many options out there and that the discussions can be spirited. There's no doubt that you can build an LED system that meets or exceeds the Gavita standard. It will likely cost more than the Gavita, and you will likely never recoup the extra cost in energy savings alone. I'd venture to say that most of us that DIY LED systems do it out of enjoyment of the design and build process rather than specific need.

Like you, I initially considered duplicating a Spydr style light but after considering my design criteria of flexibility and upgradability I instead designed a modular system of individual light bars utilizing COBs in COB holders, each capable of covering a 1'x4' space. This allows each bar to be raised or lowered independent of the others, and to tailor the light intensity to the need.

My one suggestion is to consider flexibility and ease of upgrade rather than design a fixed system like the Spydr or Growmau5's design.

edit: Just in the time it took me to write this your thread has already gone down the path of madness! LOL. Good luck.

Rider509 said:

By now you've probably read through some of the LED threads and know that there are many options out there and that the discussions can be spirited. There's no doubt that you can build an LED system that meets or exceeds the Gravita standard. It will likely cost more than the Gravita, and you will likely never recoup the extra cost in energy savings alone. I'd venture to say that most of us that DIY LED systems do it out of enjoyment of the design and build process rather than specific need.

Like you, I initially considered duplicating a Spydr style light but after considering my design criteria of flexibility and upgradability I instead designed a modular system of individual light bars utilizing COBs in COB holders, each capable of covering a 1'x4' space. This allows each bar to be raised or lowered independent of the others, and to tailor the light intensity to the need.

My one suggestion is to consider flexibility and ease of upgrade rather than design a fixed system like the Spydr or Growmau5's design.

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Not sure where you get the never recouping cost item from.. A de Gavita costs $1400 with bulb changed every 6 months in 5 years. A high quality cob light will last 50,000-100,000 hours (more than 5 years of 12/12 if you consider that would be 4,380hours ran all year for 12/12) if you make it yourself properly. The tech will continue to become more efficient and competitive making the price drop... But even if you got them now and they dropped 30% in price the next day it's still worth it long term.

Wish my plants would dry faster so I could show the massive yield I just chopped vs a hps/de hps

MeGaKiLlErMaN said:

Not sure where you get the never recouping cost item from.. A de Gavita costs $1400 with bulb changed every 6 months in 5 years. A high quality cob light will last 50,000-100,000 hours (more than 5 years of 12/12 if you consider that would be 4,380hours ran all year for 12/12) if you make it yourself properly. The tech will continue to become more efficient and competitive making the price drop... But even if you got them now and they dropped 30% in price the next day it's still worth it long term.

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Hahahahaha, are you seriously suggesting that we are going to build an LED system and be happy with it for the duration of its lifespan? You and I both know that we won't because we will be tweaking and redesigning and upgrading long before then. It's what we do. It's in our DNA. It's why we built our own LED systems. Embrace the madness!

mauricem00 said:

with natural sunlight photo inhibition occurs at 750 PPF. why would you want to run 1700 PPF. seems like a lot of wasted light. same claim LED grow light makers make about HPS. monos are becoming very effiecient. seems like getting closer to natural sunlight may be a better option . high end LED grow light makers like black dog, california light work, platinum and others seem to be taking this approach using up to 12 bands of monos ? I have been growing with T5s for years but enjoy experimenting with LEDs as well.their just seems to be many conflicting views on the best type of grow light ( multi-band VS white).

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I'm simply suguesting the led be built to provide the same quantum output as a Gavita. That way only spectrum and light distribution will be the relevamt factors rather than one lamp winning due to a higher output. PPFD (not PPF) will be dependent on the space being illuminated.

MeGaKiLlErMaN said:

Not sure where you get the never recouping cost item from.. A de Gavita costs $1400 with bulb changed every 6 months in 5 years. A high quality cob light will last 50,000-100,000 hours (more than 5 years of 12/12 if you consider that would be 4,380hours ran all year for 12/12) if you make it yourself properly. The tech will continue to become more efficient and competitive making the price drop... But even if you got them now and they dropped 30% in price the next day it's still worth it long term.

Wish my plants would dry faster so I could show the massive yield I just chopped vs a hps/de hps

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gavita is $400 and a bulb a yr is about $90 lmfao

Dr.Nick Riviera said:

gavita is $400 and a bulb a yr is about $90 lmfao

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You replace every 6 months or you're still taking a loss around 5% in yield.. Or more depending on temp of room. So a $400 base, $900 in bulbs for 5 years and boom $1300 I was going based off of when they were $475 ish. But still point being they will pay themselves off. That is around 0.09lb or 1.44oz to be that's worth the cash

Dr.Nick Riviera said:

gavita is $400 and a bulb a yr is about $90 lmfao

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In defense of MeGaKiLlErMaN I'd say that $1400 was a tpyo.

EDIT: Oops, evidently not. Just factored in total cost