Heatsinks for DIY LED lamps

testiclees

testiclees

Well-Known Member
SupraSPL said:
At least in the case of CPU coolers, fan power consumption easily erases the gain in temp droops. Almost every test was most efficient with fans running at 5V. An unexpected result but good news for those running at 12V.

I agree there is a time and place for enclosed fixtures and certain situations where you can't have them spread out. My original point is, a DIYer can achieve slightly better thermal management by spreading them out and will also enjoy efficiency gains by improving the spread in the canopy. You know me I don't mind the armada, at the end of the day it is about piles of nugs in the jar :)
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Bro, could you take a gander at this heatsink? I am considering it for use as a pontoon. I would use 1 of these on each side of my optic vero. Each heatsink would hold a pair of cxb3590@ 1.05mA. Active cooling with a 220 or 240mm fan, 1 driver per pair.

I sent the vendor a message asking about warpage and overall weight.

http://www.ebay.com/itm/NO-NAME-ALUMINUM-HEAT-SINK-SYNC-12-x-8-x-3-1-16-/291422529624?
 
SupraSPL

SupraSPL

Well-Known Member
Active cooled, each of those 12" heatsinks is good for 1130W of dissipation. I can't tell if the base is a separate piece from the fins or if it is all one piece but definitely very high cooling capability and very cheap/cm²

Edit, yep the fins are separate from the base. Not sure how much that would effect the thermal gradient but worth checking in to.
 
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testiclees

testiclees

Well-Known Member
SupraSPL said:
Active cooled, each of those 12" heatsinks is good for 1130W of dissipation. I can't tell if the base is a separate piece from the fins or if it is all one piece but definitely very high cooling capability and very cheap/cm²
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could i get by passively at 100 w per heat sink?

Thanks very much bud .
 
SupraSPL

SupraSPL

Well-Known Member
No prob man, glad to hear the optic is doing well. So because the fins are tall and so closely spaced, the passive cooling ability would be very low/cm² because the hot air between the fins would not convect, it would require a pressure differential to move the air out (active cooling). In some ways it would be worse than a solid lump of metal because the heat in the center is "trapped" and insulated. So if you are interested in passive cooling I would recommend some along the lines of heatsink USA 3.5" 4.23" 4.9" 5.88" 7.28" 8.46" 10" or 12". The cheapest/cm² is the 5.88".
 
testiclees

testiclees

Well-Known Member
SupraSPL said:
No prob man, glad to hear the optic is doing well. So because the fins are tall and so closely spaced, the passive cooling ability would be very low/cm² because the hot air between the fins would not convect, it would require a pressure differential to move the air out (active cooling). In some ways it would be worse than a solid lump of metal because the heat in the center is "trapped" and insulated. So if you are interested in passive cooling I would recommend some along the lines of heatsink USA 3.5" 4.23" 4.9" 5.88" 7.28" 8.46" 10" or 12". The cheapest/cm² is the 5.88".
Click to expand...

Thanks again. You flipped the switch to the whole cob world. Very thankful.

I went ahead and purchased the heatsink below. I plan on slicing it into 2- 15"x12" pieces and mounting cxb3590's, 2 per sink at 1mA. It is a breezy space. Am i good to go passively cooling this jawn? Also im pretty sure a perfectly matched driver has been suggested for 2- 3590s@1mA. I cant seem to locate that passage. Do you have that recommendation?

http://www.ebay.com/itm/NO-NAME-ALUMINUM-HEAT-SINK-SYNC-31-x-12-x-1-3-4-/231522134409?pt=LH_DefaultDomain_0&hash=item35e7cb6989
 
SupraSPL

SupraSPL

Well-Known Member
Yes HLG-120H-C1050 is good for a pair of CXB3590s but to warn anyone with CXA3590s it would only put out ~900mA
 
SupraSPL

SupraSPL

Well-Known Member
testiclees said:
Thanks again. You flipped the switch to the whole cob world. Very thankful.

I went ahead and purchased the heatsink below. I plan on slicing it into 2- 15"x12" pieces and mounting cxb3590's, 2 per sink at 1mA. It is a breezy space. Am i good to go passively cooling this jawn? Also im pretty sure a perfectly matched driver has been suggested for 2- 3590s@1mA. I cant seem to locate that passage. Do you have that recommendation?

http://www.ebay.com/itm/NO-NAME-ALUMINUM-HEAT-SINK-SYNC-31-x-12-x-1-3-4-/231522134409?pt=LH_DefaultDomain_0&hash=item35e7cb6989
Click to expand...
Yes that one looks much better suited for passive. It is extruded single block of aluminum, thick base, shortish fins spaced somewhat wide, and still cheaper than HeatsinkUSA. The entire heatsink is good for 228W passive cooled.
 
SupraSPL

SupraSPL

Well-Known Member
(2) CXA3590s @ 1050mA should be about 153V from a cold start but the driver maxes at 148V, so it may only put out 900mA with that setup. Maybe the current output would increase as the COBs warm up, Id like to test that. There is also some variability in Vf of the COBs so it could push in either direction. Ypu could use HLG-185H-C1050 instead but probably would not get full efficiency out of the driver because it maxes at 190V, Id like to test that also.

(2) CXB3590s at 1.05A should be only 144V from a cold start so the driver should put out full current with no problem.
 
testiclees

testiclees

Well-Known Member
SupraSPL said:
Yes HLG-120H-C1050 is good for a pair of CXB3590s but to warn anyone with CXA3590s it would only put out ~900mA
Click to expand...
Im confused about how these match up. With the recommendation above are you referring to the 72v class?

I was thinking that 36v cobs @1.05 mA would be highly efficient and also suitable bookends for brightening the edges of the optic vero's footprint.

Adding up to about 100w dissipation @about 50% efficiency to each end of the optic vero seems like an excellent way to make the whole area equally productive.

Totally open to other suggestions. The only item purchased so far is the heatsink.

Thanks folks.
 
SupraSPL

SupraSPL

Well-Known Member
Yes I was referring to 72V class. CXB3590 36V class at 1.05A should be about 34Vf each. In that case you could fit 4 on the HLG-120H-C1050 or 5 on the HLG-185H-C1050, both pretty good match.
 
S

SLITLOS

Well-Known Member
Has anybody looked at these?, The one in the pic is suppose to be passive with V29's
and 3070's. They have smaller ones with fans, have good info spec sheets. The mounting
holes for fans & cobs are part of the extrusion.
SLITLOS
 

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SupraSPL

SupraSPL

Well-Known Member
Those might be great for certain setups, although I have my doubts about is cooling performance with passive CXA3070s or Vero29s.

To compare, HeatsinkUSA 5.88X14 cost $24 and good to cool 49W passively. Takes up much more space and heavier but much better cooling performance.

In order to get that kind of cooling in a smaller package, CPU coolers can do it for ~$13
http://www.amazon.com/ARCTIC-Alpine-64-Plus-Cooler/dp/B007BVCBOE
 
testiclees

testiclees

Well-Known Member
SupraSPL said:
Yes I was referring to 72V class. CXB3590 36V class at 1.05A should be about 34Vf each. In that case you could fit 4 on the HLG-120H-C1050 or 5 on the HLG-185H-C1050, both pretty good match.
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Hmm, using one driver to power 4 cobs will be clumsy because there are 2 cxb panels separated by the optic panel.

If i went with the 72v.class would a dimmer work to help with improving efficiency. 300 more watts from the 3590s would not be needed along with the optic veros wattage.

EDIT. Looks like i should run 2x 3590 72v @.700mA on each end. is there a perfect match to power these. One driver per pair.

Thanks for your patience.
 
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DoctorDelta9

DoctorDelta9

Well-Known Member
harleydavid

harleydavid

Member
testiclees

testiclees

Well-Known Member
SupraSPL said:
Yes that one looks much better suited for passive. It is extruded single block of aluminum, thick base, shortish fins spaced somewhat wide, and still cheaper than HeatsinkUSA. The entire heatsink is good for 228W passive cooled.
Click to expand...
That heatsink arrived today. It weighs 28#+! 12x31x13/4. I'm a little psyched out about cutting it on my mitre saw. It needs to be cut 1x to yield 1-12x13" and 1-12x18".

Do i need to have it cut by a shop?

Edit this sink is very close to HSUSA 10.080" profile in weight per inch. I think its. gonna be an excellent find for my porpoise.

http://www.ebay.com/itm/NO-NAME-ALUMINUM-HEAT-SINK-SYNC-31-x-12-x-1-3-4-/231522134409
 
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