COB Build with Extruded Aluminum Heatsink idea?

E2DX

E2DX

Member
I was brainstorming about how to go about cooling 16 Cobs at 40w each (1 Cob per sq/ft 4 Cobs on a long single extrusion x4) in a 4x4 grow area without spending an arm and leg. So I came up with this idea of using Extruded Aluminum heatsink from HeatsinkUSA the 2.079 x 0.464 x 40 inch (50.8 x 11.81mm x 1016mm) its cut to length extrusion. The cobs are 36mm in diameter.

Then using a 50x50x10mm blower type fan it pushes around 7cfm. Filing down some fins to mount it flush with the heatsink and using something to seal it (duct tape) lol and have it cool the heatsink like reference style GPU where it will blow out the opposite side of the extrusion.

Total cost of all the material is around $73.15 USD and we divide it by 16 we get $4.57 to cool each COB, cheapest (possible) cooling solution I can find.
 
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BuddyColas

BuddyColas

Well-Known Member
E2DX said:
I was brainstorming about how to go about cooling 16 Cobs at 40w each (1 Cob per sq/ft 4 Cobs on a long single extrusion x4) in a 4x4 grow area without spending an arm and leg. So I came up with this idea of using Extruded Aluminum heatsink from HeatsinkUSA the 2.079 x 0.464 x 40 inch (50.8 x 11.81mm x 1016mm) its cut to length extrusion. The cobs are 36mm in diameter.

Then using a 50x50x10mm blower type fan it pushes around 7cfm. Filing down some fins to mount it flush with the heatsink and using something to seal it (duct tape) lol and have it cool the heatsink like reference style GPU where it will blow out the opposite side of the extrusion.

Total cost of all the material is around $73.15 USD and we divide is by 16 we get $4.57 to cool each COB, cheapest (possible) cooling solution I can find.
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Why not use the mid-power strips instead of cobs? They are sooooo much easier to cool and spread the heat and light out. I have tried both and the strips rule. So check out the Samsung F strips or the EB strips. I think you'll be lots happier.
 
E2DX

E2DX

Member
BuddyColas said:
Why not use the mid-power strips instead of cobs? They are sooooo much easier to cool and spread the heat and light out. I have tried both and the strips rule. So check out the Samsung F strips or the EB strips. I think you'll be lots happier.
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I had no idea they made LED strips like that I'm might have to look into them. Always thought they're purple pink rubbish LED's. I tired finding more info about the Samsung F series led strips but a'll i get is replacement led backlight in there tv's and no real documentation on the spectrum. How is light penetration with the strips compared to COB's? I'm just so confused with all the combinations Cree's Citi's Vero's and now Sam's. Seen a post by ShawnDeadHead had half 3000-4000K Vero 18's gen6 80cri and plants look really healthy with tight internodes and rockhard colas running about 30w sq/ft. SO more then likely going to go that route.
 
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1212ham

Well-Known Member
Cree's Citi's Vero's Sam's, all are very good. Strips have become very popular due to high efficiency and very dispersed light and heat. Heat sinks are as simple (and cheap) as a cookie sheet, aluminum angle or channel. 3000-4000k at 30w sq/ft will get it done! Do a search for strips here and you will find a lot of info!

Datasheet: https://media.digikey.com/pdf/Data Sheets/Samsung PDFs/F-series_Gen3_Rev0.0_2017-01-05.pdf
https://www.digikey.com/products/en?mpart=SI-B8U521560WW&v=1510
https://www.digikey.com/products/en?dc=67179
http://rollitup.org/t/bridgelux-eb-series-build.928676/page-76
 
D

dbrn32

Active Member
In my opinion, you’ll want a different extrusion. I have a handful of them cut at 24” each running 6 xml2 at about 3 Watts per diode passively. And they get pretty darn warm. Adding the fan obviously changes things, but I still don’t think you’ll have the area to cool that much power. The fin spacing is probably too tight for the fan to be effective as possible.

It’s seems the 5.886 profile would be a better option. You could go as short as 40” and have 12” oc cob spacing. Then you wouldn’t be as reliant on the fan either. 140mm pc fan will just about cover that entire extrusion as well.
 
E2DX

E2DX

Member
I just ordered 2x 350w 36v constant voltage power supplies for $69 shipped from alibaba company called WHEO NES-350-36 I know its a gamble and sometimes you get what you pay for, Almost everything is made in China these days and majority of them are iso 9001 / 2001 certified. I will sure to break out the multi-meter and get measurements, I choose CV power supply because I'm hesitant to work with high voltage close to 300V. I prob start another thread with my build sooner or later LOL. EDIT I CANCELED THAT ORDER
 
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nfhiggs

nfhiggs

Well-Known Member
E2DX said:
I just ordered 2x 350w 36v constant voltage power supplies for $69 shipped from alibaba company called WHEO NES-350-36 I know its a gamble and sometimes you get what you pay for, Almost everything is made in China these days and majority of them are iso 9001 / 2001 certified. I will sure to break out the multi-meter and get measurements, I choose CV power supply because I'm hesitant to work with high voltage close to 300V. I prob start another thread with my build sooner or later LOL.
Click to expand...
I do CV as well. You might want to check out the Meanwell LRS series CV supplies.
 
E2DX

E2DX

Member
nfhiggs said:
I do CV as well. You might want to check out the Meanwell LRS series CV supplies.
Click to expand...
No stranger to wiring electronics up I thank you so much for pointing that out. If i could give you a Like I WOULD. These LRS-350-36 would run my 16X Vero18's perfectly
 
E2DX

E2DX

Member
Randomblame said:
For COB's at only 40w you can also use cheap Intel CPU coolers like this one below. With 5-9v instead of 12v the fans should work almost silent.
A lot cheaper, btw.
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I've looked into cpu coolers kinda difficult looking for a (lot) of 16 though, might find 1-5 here and there but the shipping is gonna kill me...mabe I can call up a local PC repair shop and see if they have a bunch I can purchase. If not I'm just gonna water cool them bitches, remember aliexpress and alibaba direct from China is your friend :?
 
ChiefRunningPhist

ChiefRunningPhist

Well-Known Member
Randomblame said:
For COB's at only 40w you can also use cheap Intel CPU coolers like this one below. With 5-9v instead of 12v the fans should work almost silent.
A lot cheaper, btw.
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@E2DX too, would you think these coolers would work with the Getian 2828's??
.
Htttp:// Cant/post/links/yet.dammit
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Screenshot_2018-12-03-12-37-34~2.png Screenshot_2018-12-03-12-37-43~2.png USER_SCOPED_TEMP_DATA_orca-image-1480429449.jpeg_1543866067735.jpeg

Thinking about 8 2828's driven with HLG 320h 36A at 35ish watts/ for 4x2'..
 
Randomblame

Randomblame

Well-Known Member
ChiefRunningPhist said:
@E2DX too, would you think these coolers would work with the Getian 2828's??
.
Htttp:// Cant/post/links/yet.dammit
.
View attachment 4242968 View attachment 4242969 View attachment 4242970

Thinking about 8 2828's driven with HLG 320h 36A at 35ish watts/ for 4x2'..
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Would work!
LGA1155 means they can handle up to 95w Intel CPU's. For stady operation with COB they should be good for 60-70w. So no issues with just 35-40w COB's and the Tc. should stay below 55°C.
 
ChiefRunningPhist

ChiefRunningPhist

Well-Known Member
Randomblame said:
Would work!
LGA1155 means they can handle up to 95w Intel CPU's. For stady operation with COB they should be good for 60-70w. So no issues with just 35-40w COB's and the Tc. should stay below 55°C.
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If I lose a fan, I'm assuming I'll lose the COB not long after? If a COB drops out wIll the driver adjust current or would you recommend an inline fuse?
.
Could you just sandwich a strip of aluminium plating in between the COB & Heatsink unit (thermal paste in between) so you could have 4 on a strip?
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How could you connect them for ease of lowering or raising ect? So you only had to use one set of rachet pulleys?
.
Thanks for the help.

(8x $4.60)COB's + (8x $3.49)heatsinks + ($110)driver
=
~$175 ($174.72)

Not bad for a 4'x2' 165-170lm/w build.. Thinking about it..
 
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wietefras

wietefras

Well-Known Member
I mounted 6 COBs to an extruded aluminum strip and mounted 2 CPU coolers on top. Works great.

Even with the fans off they are fine. Although temperature goes up somewhat then (ie slightly lower efficiency). Plus I like the airflow from the fans (@9V) to spread the warm air from the leds over the canopy.

In my case I was reusing old CXB3070 COBs and mixing them at 3 different wattages, which made for much more complex wiring than when you simply use the same COBs at the same amps.

24X_CXB3590_Bottom.jpg

Still, simply buying high efficiency led strips and adding an extruded aluminium profile on top is a lot less work and gives better uniformity.
 
R

Ryante55

Well-Known Member
E2DX said:
I was brainstorming about how to go about cooling 16 Cobs at 40w each (1 Cob per sq/ft 4 Cobs on a long single extrusion x4) in a 4x4 grow area without spending an arm and leg. So I came up with this idea of using Extruded Aluminum heatsink from HeatsinkUSA the 2.079 x 0.464 x 40 inch (50.8 x 11.81mm x 1016mm) its cut to length extrusion. The cobs are 36mm in diameter.

Then using a 50x50x10mm blower type fan it pushes around 7cfm. Filing down some fins to mount it flush with the heatsink and using something to seal it (duct tape) lol and have it cool the heatsink like reference style GPU where it will blow out the opposite side of the extrusion.

Total cost of all the material is around $73.15 USD and we divide it by 16 we get $4.57 to cool each COB, cheapest (possible) cooling solution I can find.
Click to expand...
Don't use those heatsink thats the crap we were forced to use like 5 years ago pin heatsinks are alot better
 
Rahz

Rahz

Well-Known Member
Extruded heat sinks are a viable solution. I use them with fans and keep the sinks so cool they feel room temp, even on the underside right next to the chip. The 5.886 can achieve this extreme performance at 2.5 heat watts per inch. That would equal a 16" piece cooling (100w output) 40w of waste heat. Good fans should last many years.

The reason I suggest 2.5 heat watts per inch for the 5.886 sinks is because in the event of fan failure the sink will continue to operate well within spec and lamp performance will still be near 100% until the fan is replaced.

Using a 1.9 watt fan to gain a couple percent more light with the benefit of Tc in the low 40s is a pretty good deal. Putting fans on pin fins works too if passive performance isn't the primary concern.
 
Warpedpassage

Warpedpassage

Well-Known Member
Ryante55 said:
Don't use those heatsink thats the crap we were forced to use like 5 years ago pin heatsinks are alot better
Click to expand...
I was thinking about using the 1” for the samsung strips, they are about ten bucks a pop for the 4ft ones. Do u guys think there is any advantage to getting these over say L angle 1” aluminum 6063? Running the 4ft strip at about 60 watts.
 
R

Ryante55

Well-Known Member
Warpedpassage said:
I was thinking about using the 1” for the samsung strips, they are about ten bucks a pop for the 4ft ones. Do u guys think there is any advantage to getting these over say L angle 1” aluminum 6063? Running the 4ft strip at about 60 watts.
Click to expand...
For the strips that a good option just not that great for cobs
 
whytewidow

whytewidow

Well-Known Member
the heatsinks on strips works great. driven soft you don't even need a fan. I built my light with aluminum U channel. and used alum angle to make the frame. it weighs about 5lbs. and puts out over 300+ watts. and runs cool as ice. Ice ice baby...... lol
 
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