Heatsinks for DIY LED lamps

Just a quick question. Building my second light trying to save some loot on heatsinks. With recommendations set by @SupraSPL at 25cm2 for each Watt would my calculations be correct that I could run 4xcxb3590 on the heatsink USA 3.5" at 48" long? I wonder if one fan is enough or if two would work better. Any ideas?

Getgrowingson said:

Just a quick question. Building my second light trying to save some loot on heatsinks. With recommendations set by @SupraSPL at 25cm2 for each Watt would my calculations be correct that I could run 4xcxb3590 on the heatsink USA 3.5" at 48" long? I wonder if one fan is enough or if two would work better. Any ideas?

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2 fans AT LEAST for that long I have 2 36" heatsinks with 4 cxb3590's on each using 2 140mm fans on them. It doesn't get even the slightest bit warm.

Airwalker16 said:

2 fans AT LEAST for that long I have 2 36" heatsinks with 4 cxb3590's on each using 2 140mm fans on them. It doesn't get even the slightest bit warm.View attachment 3651123

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I have the same setup and cool it with one. Lol

Getgrowingson said:

I have the same setup and cool it with one. Lol

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I have 4-cxa3590 72v running an HLG-185H-C700 with one fan. Using two 18" of HS. peace

Airwalker16 said:

2 fans AT LEAST for that long I have 2 36" heatsinks with 4 cxb3590's on each using 2 140mm fans on them. It doesn't get even the slightest bit warm.View attachment 3651123

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Are those the 4.8" profile from heatsink USA? I'm DIYing a 6 Vero 18 light trying to find cost effective heatsinks

bobbuck said:

Are those the 4.8" profile from heatsink USA? I'm DIYing a 6 Vero 18 light trying to find cost effective heatsinks

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140mm fans on the heat sinks which is roughly 5.5 inches. I would say the heat sinks look a bit wider then the fans, so i think he is using the 5.886 wide heatsinks there. Best guess anyways.

bobbuck said:

Are those the 4.8" profile from heatsink USA? I'm DIYing a 6 Vero 18 light trying to find cost effective heatsinks

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Java Co is correct. I'm using the 5.886". DO NOT use 4.8". It's far to thin to disperse heat well enough.

so people are generally spacing 3590's @12.5 inches?

Thanks for the info. I'm using the V18's @ 1050. The 3.5 has a 0.3 base think that would be sufficient with 2 cobs on a 16" with a fan?

OLD MOTHER SATIVA said:

so people are generally spacing 3590's @12.5 inches?

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I did 14 inches center of cob to center of next cob

thanks and you can flower well at that distance?

Yeah in didn't have any issues

Heat Sink Calculation Help

I have posted this in its own thread, but I wanted to post it here also for more coverage.

I have pulled the heat sinks and drivers from a MarsII 900 to use in my next DIY project but I am struggling with the math.

My plan is to cut the sinks into pieces that will support 1 CXB3590 per piece to achieve my desired spread.
I will be active cooling.
If my measurements are correct the heat sink profile is 45.06 in sq.
Using the driver pictured, with 2 cobs per driver, can someone help me figure out the length per piece.
Thanks in advance.

hi guys im new to growing and to diy and im thinking on getting 9 vero 18 5000k run at 0.35A by the LPC-100-350 driver for veg and 10 vero 29 3500k run at 0.5A by the HLG185H-C500A driver for flower. Now im kinda confused wich heatsink its enought for both setup? any ideas?
ps: im totally a noob so if this setup doesnt make sense please alert me !!!
thanks in advance

if a lot of cpu coolers do a decent to good job cooling 3590's, this sould do too wright??
https://www.arctic.ac/eu_en/alpine-m1-passive.html
not manny specs, but from the dauwing i calculated aprox 1620cm².
i am still learning and can't keep it all apart yet, but it seems a little small.
would be a great sollution sinds they are avalible in europe.
what do you think??

thanxx for all info.............sorry about my english

planing on cooling a 3 cob veg.light from a 6500k, a 5000k and a 4000k, with a hlg-120h-c1400b driver with them by the way

thanxx for all info

nice video [again]..........nice practical and to the point info [again]............thanxx [again]
when all the parts are in, i will be constucting modulair passif heatsinks myself
i will copy your test as closely as possible and post the results here.
will be nice to finally contribute something to this great forum, instead of just asking stupid questions

hi everyone in cob land ....can anyone help me with my heatsink math as i am terrble at it .. i have a 39.3x6.8 inchs wide and 28mm height with 20x 2mm thick fins.i got a meanwell hlg240 700b and 10x cxb3070 that i am putting on this one heatsink at 25 watts a cob so does anyone think i can get away with running passive or am i gonna need a fan .any help would be great.i will post a link to my heatsink profile http://www.bal-group.com/heatsink_detail/52

on the topic of heat-sinks has anyone done a lapping test with the veros as they have a copper base and i know you prob cant do it with a cree as ceramic but a led chip and heatsink that was lapped to the point that they both sick together with no paste and will give the best thermal conductivity behond what paste can do and lower temps and gain proformance ,,,,,,just a thought as as hard-core pc gaming overclockers have been doing it with there cpu processors for years with clear benefits of cooler running chips with longer life spans.