# Extruded aluminum finned heatsink material



## LukeA (Mar 22, 2008)

I'm building a set of LED automotive headlights and I'm looking for some extruded, finned aluminum to use as forced-air cooling on the back of the assembly. I plan to pipe air (from the vehicle's forward motion) in over the fins to help with temperature. But I can't find any small quantity at the size I need, 4in*6in*~1-2 in high. I need the fins to run parallel to the 4in side, too. And I need 2 of them.

Does anybody know where I could find that?


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## precisionworks (Mar 23, 2008)

Can you post a drawing or sketch?


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## yellow (Mar 23, 2008)

Sorry, I am not completely sure if these are the size/kind You want, but maybe the small pics help You to check what is available.
http://www1.at.conrad.com/scripts/w...de=&p_sortopt=&page=&p_catalog_max_results=20

also I am not sure on the technical term in Your lang., but there are "profiles", obviously used to primarily heat small electrical appliances, that use some kind of "tunneled" alum. profiles. They form a barrel closed to the sides and You would only have to get the air in from one side, then it will be forced through:
http://www1.at.conrad.com/scripts/w...ISTUNGS+KÜHLPROFIL&bild_ungleich=0&akt_image=
(that damn. fan is in the way! Unfortunately they dont offer any other pics any more, but the description shows the thing also: http://www2.produktinfo.conrad.com/...-01-ml-Hochleistungs-Kuehlprofil_de-en-fr.pdf)

somehow gave info needed?


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## Norm (Mar 23, 2008)

Maybe something here http://www.alphanovatech.com/
ALPHA NOVATECH, INC.
473 SAPENA COURT, #12 
SANTA CLARA,CA 95054 
TEL: +1-408-567-8082
FAX: +1-408-567-8053
EMAIL: [email protected]


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## LukeA (Mar 23, 2008)

Here's a picture of what I want. Sorry, I only have SketchUp at home.







Here's what it mounts to. The dimensions of the block are English because the aluminum I bought was sold in English measurements. The other dimensions are metric because the threads on the P60 dropins that fit it are metric. The 6 10-32 holes were intended to mount the heatsink, but I haven't made the part yet so their locations can change.





BIG version


yellow: Your first two links don't work for me. Something about cookies, as far as I can tell.

Norm, the biggest heatsink in your link would work. I'll look into it. This one, specifically.


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## yellow (Mar 23, 2008)

Sorry, I checked the links after posting and they worked, but now I also get those "cookie" messages.

I took some pics from the print version instead:

2 of these "Profiles":





probably a suiting sink plate:




the one in the middle is a bit over Your 6"x4"x1-2"


to look at them on the site, open www.conrad.at, 
then type in these 6-digit "Best.-Nr." (f.e. 188816) into the smaller field at the left named "Art.-Nr." 
and hit "suchen"
(ignore the cursor jumping into the smallest field after typing in the 6 digit number)


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## LukeA (Mar 23, 2008)

yellow said:


> probably a suiting sink plate:
> 
> 
> 
> ...



I think that might be the ticket. I just wish the dollar wasn't so weak against the Euro right now.


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## will (Mar 23, 2008)

this might be another source

http://www.surplussales.com/Heatsinks/HeatSink1.html


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## LukeA (Mar 23, 2008)

yellow said:


> Sorry, I checked the links after posting and they worked, but now I also get those "cookie" messages.
> 
> 
> to look at them on the site, open www.conrad.at,
> ...



I can't for the life of me find United States in the list of countries Conrad ships to.


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## bfg9000 (Mar 23, 2008)

I strongly advise you to check with local electronics surplus and aluminum recyclers, because a lot of obsolete industrial/scientific equipment, amplifiers and computers use such heatsinks.

In particular, many Slot-2 Xeon processors use a fanless 4x5x1" heatsink that are available here for around five dollars, _complete with processor_. Some of them even have heat pipes incorporated into the design, which isn't too surprising for something that originally cost well over a thousand dollars less than ten years ago.


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## yellow (Mar 24, 2008)

That pic was meant just for info purposes, there must be some much larger vendors at Your place (Radio Shack?).
Should offer much better prices, I think that prices here are expensive.
(if there is really no other souce, I see no reason Conrad should not send to the US). :thinking:


Probably computer stores are a source also. 
Pentium II sink almost fits Your size requirements. 
Usually these shops have a very large "chest" with old, no longer actual parts.
Or maybe You know someone, who could ask at the computer dept of his/her school/university/enterprise.
Thats where I got my Alum sinks from - when I see old computers to be "thrown away", I ask if I could get some parts out.


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## tnuckels (Mar 24, 2008)

Lots of “cool” stuff over at NewEgg.com and other PC supply houses that deal in smaller bits and pieces. I recently bought a replacement heat sink and cooling fan for an ATI graphics card whose fan had died and was overheating. All copper w/5vdc circulating fan. With all the kids moding their PCs for show, there’s lots of fun stuff to choose from, even some water cooled.

BFG9000 is right about the junk yard. I worked at one years back and we’d get surplus and scrapped electronics in all the time. You pay by the pound, plus a small premium gauged to how prosperous you look, so dress down if you go this route.

Happy hunting …

*EDIT:* I also remember reading about different surface treatments affecting the heat transfer capacities of aluminum fins. IIRC the final smooth coating on extruded aluminum reduced its effectiveness, with a highly polished surface being even worse. Seems the article said that a rough coating of flat black paint, maybe like high temp stove paint (?) worked the best, which is why you’ll often see this treatment on stereo components. I’ll see if I can dig up the article and link to it.

Found it:
Here ~ http://www.molalla.net/~leeper/led.htm
And more specifically here for heat xfer info ~ http://www.molalla.net/~leeper/heat.htm


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## LukeA (Mar 28, 2008)

Today I asked the IT guys at my school and they gave me a PIII on a heatsink for free. It's small enough that I need one and a half of them per side and it's kind of purple, but I couldn't beat the price. Now I just have to see if they have two more...


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## Rinspeed (Mar 28, 2008)

I have some at work I could hook you up with. It doesn't have quite so many fins as the one you have pictured but might work fine. Send me an e-mail and Monday I'll get a couple pics and/or dimensions.


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## LukeA (Mar 28, 2008)

Rinspeed said:


> I have some at work I could hook you up with. It doesn't have quite so many fins as the one you have pictured but might work fine. Send me an e-mail and Monday I'll get a couple pics and/or dimensions.



This is the one I got for free. 







I'll take you up on that offer if I can't get two more of those PIII heatsinks.

Oh, and the dimensions of the actual parts are 3*6, not 4*6 and the centers for the rows of emitters are 20mm apart instead of 25.


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## warlord (Mar 29, 2008)

Maybe this?

You can also do a google search for "passive heatsink" They all tend to be pretty large because of the way they function. Also old Xboxes have similar passive heatsinks...

And this would be fine if you want to design your own.


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## RPM (Mar 29, 2008)

If Rinspeed doesn't have the right stuff, drop me a PM, I have exactly what you need. 

R-


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## Torque1st (Mar 31, 2008)

Pittsburgh should have plenty of used computer dealers, surplus material dealers and metal scrap yards. Look in the yellow pages, make some calls, then visit a few. I have several very similar to the one in your post #5 as well as many others I use on experimental projects all the time. They gradually get whittled down over the years and have to be replaced with new scrap yard "treasures".


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## Rinspeed (Apr 3, 2008)

Luke,

Here is the heat sink I have. It's 1.75" wide X 12 long and the fins are .625 high. Just let me know if you need it.


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## LukeA (Apr 3, 2008)

This forum is great! I haven't had another opportunity yet to ask at school but I should soon.


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