Heatsinks for DIY LED lamps

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getsoutalive

Well-Known Member
SupraSPL said:
There are similar heatsinks available in the US from Nuventix, selling on Digikey. I think the vertical orientation of the fins would be awesome for passive cooling, as another poster here mentioned a few pages back. The downside though, they are just about the same price as the Alpine 11 and they may not be up to the task of a 53W COB?
http://www.digikey.com/product-detail/en/NX301101/1061-1092-ND/3505755
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Careful, that is a much smaller sink. It is rated up to 40W, which includes the optional fan. It is rated much lower as a passive device. It may be just fine for the V10 depending upon drive current Abiqua will use obviously, but not that beefy.
 
epicfail

epicfail

Well-Known Member
epicfail said:
So what you're saying is I went overboard, no surprise its what I'm good at.

My setup:
5.88" x 18" = 4680cm²
Sanded to 1000g and anodized black
CXA3070 AB X 2 @ 1050mA = 76W dissipation
61cm²/W so it should be just under 40% efficient if run passive.

The thing is I also have a 12V 140mm 3000 RPM PWM fan mounted on to it and its a power hog which I guess is actually bringing the overall efficiency down. Right now the ambient temps in my tent are 22.5C at this time of year. The hottest part of the heatsink is only 25.8C according my IR thermometer, I guess I could just turn the fans off but that means I would need to add the circulation fans again. I removed them because the PC fans move so much air they weren't needed, I should see what uses less wattage the 4x PC fans or 2x 6" clip fans.

I'm lazy and its probably just going to stay the way it is for a while at least because everything seems happy.
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I unplugged the fans and let the heatsink temperature stabilize for a few hours (I forgot), ambient was .5 degree higher @ 23C and the heatsink was 36.4C (about 11C increase) at the hottest spot I could find with the IR thermometer. I'm sure I could run passive with those temps. But like I said, the fans move so much air in my small space that every leaf moves. I actually removed my 6" clip fans because they weren't doing as good of a job circulating the air as my heatsink fans were.
 
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Tazbud

Well-Known Member
I'm having a struggle finding anything but china direct here, any thoughts on these Intel CPU coolers, they are $20 cheaper than the others mentioned (here), they must be an older model not much made sense on the intel site.
 
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Tazbud

Well-Known Member
The ones I can get locally are $12 delivered, Rosewill, $35. Here's another.

Edit: specs from a similar application model:
  • Dimensions 93 x 93 x 32mm
  • Fan Speed (RPM): 1200rpm -2800rpm
  • Fan Directions: 4
  • Pin of the fan: 4
  • PWM function: Y
  • Acoustical Noise (dBA): 25
  • Rated Voltage (VDC): 12
  • Rated Current (A): 0.41
  • Bearing Type: Ball Bering
  • Heat Sink Masterial: Copper / Aluminum
  • Weight of cooler: 230g
  • TDP (Thermal Design Power) 73W
 
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AquariusPanta

AquariusPanta

Well-Known Member
Tazbud said:
I'm having a struggle finding anything but china direct here, any thoughts on these Intel CPU coolers, they are $20 cheaper than the others mentioned (here), they must be an older model not much made sense on the intel site.
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These are the best choice imo due to performance and cost - http://www.newegg.com/Product/Product.aspx?Item=N82E16835186070

I've tried these; they work well and are $3 cheaper than the Arctic Alpine 11 Plus - http://www.ebay.com/itm/New-Original-Intel-Socket-775-CPU-Cooling-Fan-and-Heatsink-E97375-001-/230771615333?ssPageName=ADME:L:OU:US:1120

The only issue with the Intel CPU I linked is that it does get warm and that warm air does get blown onto the plants, sometimes resulting in 'taco' leaves. This, of course, can be avoided by raising the lights above 12" and running the fan at a lower voltage (not entirely sure it's doable at 5V or 9V, probably so though).
 
SupraSPL

SupraSPL

Well-Known Member
Good link AP. I tested one similar to that. These have copper pads and the heatsink weighs in at ~450gr, a hefty chunk. Excellent performance at cooling but there is something strange going on with the fan, I was not able to control fan speed directly by changing voltage. I like the way it blows air into the canopy (maybe not at full blast though). Another limitation, nothing larger than CXA3070 would fit on the copper pad and even the 3070 corners hang off slightly.

http://www.ebay.com/itm/Intel-Heatsink-D60188-001-Socket-LGA775-3-5-CPU-Fan-Copper-Heatsink-/161494327359?pt=LH_DefaultDomain_0&hash=item2599cfe03f

DSC07689a.jpg DSC07691a.jpg DSC07694a.jpg

5V -> .11A = .55W
7.5V -> .051A = .38W
9V - > .063A = .567W
12V -> .087A = 1.04W
 
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FrozenChozen

FrozenChozen

Well-Known Member
SupraSPL said:
Good link AP. I tested one similar to that. These have copper pads and the heatsink weighs in at ~450gr, a hefty chunk. Excellent performance at cooling but there is something strange going on with the fan, I was not able to control fan speed directly by changing voltage. I like the way it blows air into the canopy (maybe not at full blast though).

http://www.ebay.com/itm/Intel-Heatsink-D60188-001-Socket-LGA775-3-5-CPU-Fan-Copper-Heatsink-/161494327359?pt=LH_DefaultDomain_0&hash=item2599cfe03f

View attachment 3309513 View attachment 3309514 View attachment 3309515
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Been rocking my Feit cobs on these... I have em on an adjustable voltage wall wart (1.5v-12v).... They're the ones I was telling @SupraSPL about; I have them running slightly cooler than ambient room temp with the fan at 12v (only by a couple degrees F though). My cobs are 36.1 vf at about 410 ma once stabilized for a couple hours, I have had no problem reducing the fan speed. Although it won't it start at 3v or below, I can start it higher then go down to 3v, temp hits about 85F (29-30C) at 3v typically I stay at 6v and see temps around 78F(25C).... Passive running at about 95F (35C).... Mine look as though the blades on the fans are more protected/ less dangerous!
I have found that copper core has been more helpful in passive heat dissipation. Correct me if I am wrong, but it is the natural properties of convection with copper to be able to "cool" faster/ more efficient than aluminum, right? Always check a local PC repair shop for heatsinks before ebay! And Thrift shop for Wall warts!
Anyway I thought I'd share my experience with 'em!
IMG_9313.JPG IMG_9279.JPG
 
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Tazbud

Well-Known Member
Thanks for the other links. Even that auction (@99c) is 32$ Shipping, i'm understanding that they are a standard heatpad size, copper core, copies of each other with differing height h/s (that one looks much deeper than the Intel FC).. those aside, its down to he fan quality...
 
SupraSPL

SupraSPL

Well-Known Member
FC, copper has a higher thermal conductivity than aluminum (400 vs 200), so it can move heat "faster". But when it come to transferring that heat into the air, copper is at a disadvantage to aluminum because aluminum is cheaper and lighter. So the combination of copper pad with aluminum fins makes sense, as long as there is a good thermal interface between the two parts of the heatsink.

I have one of those adjustable adapter from Radio Shack. It is super convenient but for extended use, I did notice that they are very low efficiency (~30-50%). Not a major issue but worth mentioning. With your setup FC, I think 5V or 6V is a great setting to get the highest efficiency for your system overall.

The pic you posted demonstrates the situation very well. Despite some of the chip hanging off the edge, I still measured very good thermal performance from the heatsink I linked to. maybe this pic can show how the copper pad is slightly elevated:
DSC07724a.jpg
 
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Tazbud

Well-Known Member
Great pic thanks. I'm not picturing what the part the bracket has to play, can be removed, maybe the fans can be reversed? Anyhow, bought an Intel model to try ($12) I have 90mm fans running @ 12v from my bars and they just jostle things around nicely from the 5-6" from the tops, the airflow is kinda rough through mine pre-fan though so it tends to chuck air everywhere.
 
FrozenChozen

FrozenChozen

Well-Known Member
Tazbud said:
Great pic thanks. I'm not picturing what the part the bracket has to play, can be removed, maybe the fans can be reversed?
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the bracket is pre fab'd non removable, its there to bolt into a computer mother board, I use it as mounting brackets or with screw-in eyelets to hang with.... why reverse the fan? Seems like the idea of active cooling requires a fan to be blowing on the item to be cooled....o_O
 
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Tazbud

Well-Known Member
Ha, yeah, tinkering, I have an idea brewing involving using round plastic pipe in a build.. a bit of a complicated application, semi-outdoors, perhaps even needing to pull the CPU coolers apart in the process. Cobs/ round heatsink in pipe T's with fans used on intake and outlets

My current bars pull air across heatsink and blow it over plants. The 'heat' i get anywhere (at .7a) is barely measurable. It's probably completely inefficient but then the air flow seems almost redundant (they just don't get hot, even without fans running)
 
coolbreez1

coolbreez1

Well-Known Member
I have six Vero29 mounted on the arctic alpine 11 running at 2.1 amps and they seem to be working fantastically. They are starting/Vegging a bunch of plants in a 8 by 4 space. The temp goes up about 1 degree per hour, and I would add that active cooling helps circulate the air in the grow space which is essentially always good...

Its not fancy but seems to be working well so far, I would also add that the alpine 11 is very easy to mount because of the 4 screw holes.
 

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AquariusPanta

AquariusPanta

Well-Known Member
coolbreez1 said:
I have six Vero29 mounted on the arctic alpine 11 running at 2.1 amps and they seem to be working fantastically. They are starting/Vegging a bunch of plants in a 8 by 4 space. The temp goes up about 1 degree per hour, and I would add that active cooling helps circulate the air in the grow space which is essentially always good...

Its not fancy but seems to be working well so far, I would also add that the alpine 11 is very easy to mount because of the 4 screw holes.
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You beat me to it! Haha, I was thinking about doing something similar like this with some AA11P's and thin aluminum angles. Although I do like the mobility of individual COBs a whole lot more so I may ditch the idea.

By the way, a grow room in the bathroom!? Bahahaha. The COB fixture looks legit. How difficult was it to screw down the COBs into the HS?
 
coolbreez1

coolbreez1

Well-Known Member
It is in a bathroom at the time being... It make sense, already has a vent fan, small space, water, drain, all white... Perfect for starts and veg!

I was able to do it without a drill press! but a drill press would have made it all a lot easier. I marked the location for the holes, pre-drilled them, and then put the screws in once before I mounted the COBs, to make sure all of the screws fit right and went in easy. Its a real bummer to be fighting a screw when you are attempting to mount the COB. The corners of the square bed on the COB overhangs the heat sink a tiny amount, but it is not a portion that has any of the LED array mounted on it.

Mobility of individual cobs is nice, but then you need many more plugs and have to consider how to power each heat sink fan. This way all 6 fans run on one power supply and each LED has a power supply and all 7 power supplies are wired into two power cords, and in theory I could have run them all into one cord...

I am thinking for flowering 2-3 COBs per plant, all the same components, just different arrangement.
 
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