My First Cree cxa3070

Hello everyone,
Just a little background about myself, I have been a member here for a while now and have been an avid reader. I have grown in soil and DWC, both under CFLs. I had ok results, but didn't get to really put the time in that it required. I am now ready to start my first serious grow and plan to make a grow journal on here.

I just ordered a:
Cree cxa3070 3000k from Digikey - $40
Meanwell LPC-60-1400 from Jameco - $18
Arctic Silver Alumina Thermal Adhesive from Amazon - $6

Total - $72

This should all be in by this next week. I have a cpu heatsink with fan that I plan on mounting the LED to with the thermal adhesive.

I also have some seeds
2 Girl Scout Cookie
1 Black Domina
2 Kandy Kush
1 Golden Haze
1 Blue Widow

Let me know what you guys think, I am excited for this next week!!

Sounds like a good project. My friend just did his first grow with a CXA3070 3000K Z4 bin driven at 1.4A (52W) on a CPU cooler. In organic soil. He got 44gr of very impressive med grade bud (Sour Jack). So that is one data point of what can be done and I am sure he will improve as he goes. What heatsink are you going to use?

SupraSPL, thanks for stopping by and giving your input. I have read a lot of your diy LED threads and actually that is how I finally decided on my hardware. I have been looking all around for a grow with a single 3070 but haven't been too lucky, but 44g is amazing for this one LED!

When I ordered my LED I could only find a z2, but with this being my first lamp build I figured I could just add one later. The heatsink I am using is from an old quad-core pc build. I have that Arctic Thermal Adhesive and I am going to clean the heatsink, sand it and polish it. Then I plan on putting an adequate amount of adhesive on it, placing a book or something similar on the LED to allow the adhesive to properly set.

That adhesive is permanent. If you want to do a future upgrade using that heat sink you would be better served using a good thermal paste and a holder for your led. You would also be able to reuse your Z2 since it wouldn't be destroyed in the removal process.

The heatsink and fan combo should compliment your CXA and eventually your plant's buds.

I was going back and forth with the idea of getting a holder and thermal paste instead. I ultimately looked at it like this, I don't think I am ever going to need to remove the LED from the heatsink unless it is already non-functional. I would never need this LED for anything other than growing, and if I built a bigger light setup in the future I think I would just buy more LEDs to fit the design instead of harvesting this one. This is my first one though so who knows, maybe I will use the adhesive and regret it lol At least I will know, and it will be mounted to a sufficient heatsink/fan.

apoulin said:

I was going back and forth with the idea of getting a holder and thermal paste instead. I ultimately looked at it like this, I don't think I am ever going to need to remove the LED from the heatsink unless it is already non-functional. I would never need this LED for anything other than growing, and if I built a bigger light setup in the future I think I would just buy more LEDs to fit the design instead of harvesting this one. This is my first one though so who knows, maybe I will use the adhesive and regret it lol At least I will know, and it will be mounted to a sufficient heatsink/fan.

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That sounds like a good plan. Arctic Silver epoxy is pretty good at heat transfer so your emitter should last for a very long time as long as the fan keeps turning. Happy growing!

Thank you, I am very excited to get in and get this going!! Everything should be in by this weekend, and my thoughts are that I get this first LED set up and get hopefully a clone, but at least seedlings under it by next week. I was thinking of going with a 5 gallon DWC bucket with 4 pots in the top and using GH Flora nutes.

Hopefully if all goes well I can start planning to add some more LEDs by the end of next week. I have a few more single heatsinks and I am thinking that I will have quite a bit of the adhesive left over. It costs right around $60 for each 3070 setup, so my thoughts are keep the lights modular and add as many $60 LED lamps as needed/possible. In the end I will have a set (2-4) of these modular light units that can be moved independently, then eventually get a set of 4 or 6 LEDs and mount them to a large heatsink for the main light and then use the modular lights to place around where necessary.

I am so excited!! I am picking up my Cree 3070 and the Thermal Adhesive right now, I already have the heatsink. So when I return, I will be unboxing and adhering the COB to the heatsink.

Alright so here we are!

1. We have the Cree cxa3070 3000k z2 and Arctic Alumina Thermal Adhesive
2. Part A and Part B of the mixture, the 2.5g syringes were a lot smaller than I thought
3. Cree COB, Amazed at how small this is.
4. Cleaned and sanded heatsink
5. 1:1 mixture of Part A and Part B for the Thermal Adhesive
6. Applying the adhesive to the back of the COB
7. Placing the COB on heatsink w/adhesive
8. I used two hand clamps on either side of the COB to hold it firmly in place while the adhesive sets
9. One clamp on each side, only on edge of LED. NOT clamped on to any yellow surface, only white surround of LED.

I wanted to make a step-by-step with what I did, in case there are any questions or in case there is an error in my procedure.

I now have my led setting and the adhesive will have plenty of time to dry (48hrs+) before the led will be turned on. All I need is the driver, which is currently in transit.

Here it is, after a night of setting. I was worried about how much adhesive to put on, I put enough on to see excess squeeze out of each side. I had to work quickly to clean it up because the adhesive started hardening rather quickly. I used a paper towel and iso alcohol to wipe up as much of the excess adhesive as I could. The led feels cemented to the heatsink, I do not feel any corner moving the tiniest bit. I think my first time adhering a COB to a heatsink is successful!!

I looked up my driver and it should be in tomorrow! So hopefully I will be testing it and posting that stuff on here then. I plan on going to Harbor Freight and getting some 18ga wire and electrical connectors to be able to wire up the driver.

Let me know what you guys think!

apoulin said:

Let me know what you guys think!

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Looks off center. Just kidding!

Mo! said:

Looks off center. Just kidding!

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haha stink bro!

apoulin said:

Let me know what you guys think!

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looking great man! Nice and straight forward using the adhesive

I was a little when I was reading the shipping tracking info, the correct dates are 1/27/15-1/30/15 haha oops

Looks off center. Just kidding!

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I got this while on my phone at work, I couldn't wait to get home and check lol you are correct, slightly to the right
I guess that is what happens when you multi-task, that was the product of rum & cokes and DIY LEDing

But that brings up a good point, in the future I would trace out with a pencil where I wanted the LED. I remember thinking this when I turned the LED over after I applied the adhesive. I did a lot of centering, but after pressing i down and trying to wipe up excess adhesive. It proved difficult to center it and clean it and properly apply pressure, a pencil guide would have been ideal.

making progress guys, making progress

apoulin said:

I was a little when I was reading the shipping tracking info, the correct dates are 1/27/15-1/30/15 haha oops

I got this while on my phone at work, I couldn't wait to get home and check lol you are correct, slightly to the right
I guess that is what happens when you multi-task, that was the product of rum & cokes and DIY LEDing

But that brings up a good point, in the future I would trace out with a pencil where I wanted the LED. I remember thinking this when I turned the LED over after I applied the adhesive. I did a lot of centering, but after pressing i down and trying to wipe up excess adhesive. It proved difficult to center it and clean it and properly apply pressure, a pencil guide would have been ideal.

making progress guys, making progress

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Oh bro he's only joking it's absolutely fine where it is
So what you going to put under it?

Everything is in good fun over here

I am not sure yet. I might be able to get some clones, if not I have some seeds. I was thinking of having 4 net pots so depending on how many clones I get, I might be starting to germinate 0-4 of my seeds.

Currently have

2 Girl Scout Cookie
1 Black Domina
2 Kandy Kush
1 Golden Haze
1 Blue Widow

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Some of the seeds are feminized, but I lost the paper saying which is which. They are also a little over a year old, stored in a fold of cardboard and in a plastic ziplock bag. So I am not sure what seeds will work, worst case scenario I will do them all and just put some in dirt....hmm that sounds like a pretty good idea huh?! Might as well, I am planning on adding more leds in the near future anyways

apoulin said:

Everything is in good fun over here

I am not sure yet. I might be able to get some clones, if not I have some seeds. I was thinking of having 4 net pots so depending on how many clones I get, I might be starting to germinate 0-4 of my seeds.

Currently have


Some of the seeds are feminized, but I lost the paper saying which is which. They are also a little over a year old, stored in a fold of cardboard and in a plastic ziplock bag. So I am not sure what seeds will work, worst case scenario I will do them all and just put some in dirt....hmm that sounds like a pretty good idea huh?! Might as well, I am planning on adding more leds in the near future anyways

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sounds like a nice selection you got there, your girl scouts from clone?

lol I just noticed the

@Goldy

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Yes GSC are from clones

apoulin said:

Yes GSC are from clones

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be interesting to see how they do under the one. Planning me some CXA3070 panels at the moment