Heatsinks for DIY LED lamps

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chechnya

New Member
Hey guys,

What do you think about using fat 2U server coolers (smth like these http://www.ebay.com/itm/Intel-Xeon-2U-Passive-Heatsink-Dual-Core-5XXX-Series-LGA771-D36871-001-FRJ-/181749280545)? Of course not for that price, you can get this old stuff on craigslist rather cheap.
Will it be enough for running 2 CXA2540@1400mA? Planning to use them with Zalman 120mm coolers @9V. According to Cree, 2 COBs use 106W, assuming ~25% efficiency it's about 80W of heat. I guess CPUs are running approximately the same, but not 18 hours per day)

Also how hard things can be with drilling of copper? I've zero exp with it and only hand drill so it kinda bothers me. My Tyco connectrors require drilling
 
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CanadianONE

CanadianONE

Well-Known Member
chechnya said:
Hey guys,

What do you think about using fat 2U server coolers (smth like these http://www.ebay.com/itm/Intel-Xeon-2U-Passive-Heatsink-Dual-Core-5XXX-Series-LGA771-D36871-001-FRJ-/181749280545)? Of course not for that price, you can get this old stuff on craigslist rather cheap.
Will it be enough for running 2 CXA2540@1400mA? Planning to use them with Zalman 120mm coolers @9V. According to Cree, 2 COBs use 106W, assuming ~25% efficiency it's about 80W of heat. I guess CPUs are running approximately the same, but not 18 hours per day)

Also how hard things can be with drilling of copper? I've zero exp with it and only hand drill so it kinda bothers me. My Tyco connectrors require drilling
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Most of these heatsinks would be in servers and running 24/7 I would think.
 
C

chechnya

New Member
I meant that CPUs are not running at full load 24/7. Idle power consumption is more like 30W i think. Also fans in servers are pushing through much more fresh air than my ~50cfm case fan.
 
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DocCox

Well-Known Member
I work on servers almost every day.
These heatsinks are meant to be in a case, which usually has 2-8 fans per RU on the front, and 0-8 on the rear along with power supplies loaded with fans . The heatainks themselves sometimes have fans as well. These are extremely thick high backpressure and and very short fans at 40mm or so and most run at extreme RPMs.. Their reliability is below that of an 80-120mm brand name fan by a lot. The servers generally run at 80-100% load at all times, because an underutilized server is like throwing 20k away day one and a hundred bucks daily after that for space, bandwidth, cooling, and electricity.

Most datacenters push a wall of chilled air into these things (cold side) and isolate and evacuate heat on the hot isle.

Servers run five 9s (99.999%) uptime only because they have redundancy, meaning you can lose about 30-50% of a device and it keeps working. Everything can get hotswapped with the exception of CPUs normally.

They may work if you constructed a large ridgid channel for a 6" or 8" inline to pull air through them at full blast - but if you apply a 50W load to them and they just have 1 fan it's likely you will have a very poor and load cooler. If you apply one of them to a desktop processor it will overheat or thermally throttle.

We have thousands of these for free, and I opted not to use them. They would probably passively support a 20-35W load just because they are a hunk of metal.
 
AllDayToker

AllDayToker

Well-Known Member
Would a vero 13 with like a small 10w driver be good for seedlings and clones? Plan on running it 24/0. It's probably under a sq ft total so it's small.

Figured I'd just slap it on one of them artic heatsink fan combos things for computers.

Would that work alright?
 
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C

chechnya

New Member
DocCox said:
They may work if you constructed a large ridgid channel for a 6" or 8" inline to pull air through them at full blast - but if you apply a 50W load to them and they just have 1 fan it's likely you will have a very poor and load cooler.
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I guess server coolers are running at full blast in order to pull air through whole ~60cm with obstacles.
Look at CPU coolers, fin density is more or less the same and copper should work better that aluminum IMO.
I'm gonna try some of these, but @1200mA or less

The only thing i really worry about is drilling copper plate..
 
SupraSPL

SupraSPL

Well-Known Member
If I am looking at the right specs, that heatsink is over 2 pounds of cooper. It has a lot surface area and very thick base. With a slight breeze blowing into it that should be a monster cooler.
 
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DocCox

Well-Known Member
Yea I looked at the one that was linked to, one of that physical size is unusual to come across.

@PurpleBuz they just weren't what I was looking for. HSusa was affordable and easy, and wonderful with ratchets to adjust. We recycle the heatsinks at work, so they are never wasted.

If your serious about using 1-2ru coolers passively just pay close attention to the fin orientation, and if active make sure it was built for it or understand the implications of the fan size and shape. If everything you find is a 2lb block the oscillating fans in your tent would probably be adequate.

As for drilling/tapping copper, as long as your bits are of average quality and oil is used it's doable with a normal handheld drill. Don't hit any heatpipes in the process (usually visible). Shop around for one's with a large enough socket design to support whatever optics or reflectors you want to run, usually it's a fair guide to the TDP design of the heatsink as well.
 
Hampsteri

Hampsteri

Well-Known Member
Vero13 is like ~35w max so it would be vero18 if you want ~50watts but afterall a difference is not so huge cos Vero18 is 10,70e and those are 8,45e (if bought more than five). I remembered Vero18 price wrong.
 
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qwerkus

qwerkus

Well-Known Member
Does anyone know a good retailer in europe for this type of track lights:

I've been working chinese resellers on ali for a week now, and transportation costs are just prohibitive. After all, we need only the empty case, including reflector an track adapter, and make very convenient heatsinks out of it.
 
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littlejacob

littlejacob

Well-Known Member
Hampsteri said:
Vero13 is like ~35w max so it would be vero18 if you want ~50watts but afterall a difference is not so huge cos Vero18 is 10,70e and those are 8,45e (if bought more than five). I remembered Vero18 price wrong.
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Bonjour
I plan on build a vegg light...but in a low box (80cm/ 31 inch) I prefer a lot of small cob to allow me to put the lights as close as I can.
If I go with V10 I will have to wire too many cob for my 10sq/ft box...V29 too hard...so I have to choose between V13 &V18 or maybe another brand if I dare!
Have a great day ★
 
qwerkus

qwerkus

Well-Known Member
DocCox said:
I work on servers almost every day.
These heatsinks are meant to be in a case, which usually has 2-8 fans per RU on the front, and 0-8 on the rear along with power supplies loaded with fans . The heatainks themselves sometimes have fans as well. These are extremely thick high backpressure and and very short fans at 40mm or so and most run at extreme RPMs.. Their reliability is below that of an 80-120mm brand name fan by a lot. The servers generally run at 80-100% load at all times, because an underutilized server is like throwing 20k away day one and a hundred bucks daily after that for space, bandwidth, cooling, and electricity.

Most datacenters push a wall of chilled air into these things (cold side) and isolate and evacuate heat on the hot isle.

Servers run five 9s (99.999%) uptime only because they have redundancy, meaning you can lose about 30-50% of a device and it keeps working. Everything can get hotswapped with the exception of CPUs normally.

They may work if you constructed a large ridgid channel for a 6" or 8" inline to pull air through them at full blast - but if you apply a 50W load to them and they just have 1 fan it's likely you will have a very poor and load cooler. If you apply one of them to a desktop processor it will overheat or thermally throttle.

We have thousands of these for free, and I opted not to use them. They would probably passively support a 20-35W load just because they are a hunk of metal.
Click to expand...
+1 airflow tend to be rather bad on server heatsinks. BUT if you use a blower type fan, or a high pressure one, you can achieve decent performances.
 
AllDayToker

AllDayToker

Well-Known Member
SupraSPL said:
The amount of canopy each will cover depends on power, spacing, lenses, distance to canopy etc. A good starting point, we can space them as wide as possible on the heatsink. This diagram is to scale and you can count pixels with the MSpaint line tool to get the exact distances once you get an idea how you want it set up. I put the COBs on the corners a bit further from each edge and the COBs in the center closer to the edge
View attachment 3497734
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You said that this was to scale and I can count the pixels in paint to get exact distances.

So is each pixel an inch?

Will this be the best method you would suggest for the best coverage?
 
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