• These commercial threads are for private transactions. diyAudio.com provides these forums for the convenience of our members, but makes no warranty nor assumes any responsibility. We do not vet any members, use of this facility is at your own risk. Customers can post any issues in those threads as long as it is done in a civil manner. All diyAudio rules about conduct apply and will be enforced.

North America Heat Sink Group Purchase

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
Hi Everyone,

I have found a heat sink distributor for Seifert extrusion number KL-271:

An externally hosted image should be here but it was not working when we last tested it.


With the fins oriented vertically, this heatsink measures 12" wide, 8" long, 3.25" thick, and has a 1/2" thick back plate. A singe 8" (200mm) length of this heat sink with black anodize and natural convection is rated for 0.18c/w :bigeyes: or approximately 140-150 :hot: watts dissipation with a 25c temperature rise.

One of these would comfortably run a stereo Mini-Aleph. Two of these sinks would provide 0.09c/w of cooling that can dissipate approximately 280-300 watts and should be sufficient for a 100wpc Aleph-X monoblock or even an Aleph 2 monoblock.

The distributor has a minimum order of 10 pieces, which is more than most people might want, so I have inquired about the possiblity of a group purchase and different quantities and price points.

To give you an idea of cost, the unit price for 10 of these heatsinks is approx $60 each (not including shipping).

I will be able to provide more details shortly...

Any interest?? I will post more details shortly, and if there is sufficient interest, I'll set up a wiki...

Eric
 
I'd be interested in four pieces, if the price can be brought down with higher quantities.

I had purchased 12 pieces of extruded heatsinks from M&M Metals for about $300 shipped. The heatsinks were 8" in length, 6.695" tall with alternating 2.2" and 1.2" fins, with a base thickness of 0.2". Obviously the one you're suggesting is much larger, but I could buy four of the other heatsinks for the price of two of the larger ones. In case you want to look up the extrusion I used, it's MM11645 located here:

http://www.mmmetals.com/pages/extru...back_heatsink_aluminum_extrusion_4_and_up.htm

You'll need to scroll down just a little bit to find it. The thermal resistance they list (0.8C/W) is for a 3" length.
 

BrianGT

Retired diyAudio Moderator
2002-01-21 2:42 pm
near Atlanta, GA
www.chipamp.com
Here is an amp that uses the 200mm version:
http://www.passdiy.com/gallery/alephx-p3.htm

Ignoring the piles of large heatsinks in my basement, I would be interested if the price dropped. I am sure that if you checked different vendors, you could a similar extrusion for cheaper.

I also like the MM heatsinks that Rob (maxhawk) used, and they have been used in by others for Aleph 2 amps:
http://www.passdiy.com/gallery/aleph2-p1.htm
http://www.passdiy.com/gallery/aleph2-p2.htm

Rob's chassis:
http://maxhawk.flagshiphosting.com/projects/Leach/index.htm
or
http://www.briangt.com/gallery/leachamp-5channel

Chassis I helped another friend make:
http://www.briangt.com/gallery/jeetamp

MMM might also have more beefy extrusions if you give them a call.

--
Brian
 

BrianGT

Retired diyAudio Moderator
2002-01-21 2:42 pm
near Atlanta, GA
www.chipamp.com
kestrel200 said:
IS it difficult to cut these into smaller lenghts, ie. reduce the 8" length to 3.5 to 4"? Can a table saw do this?

I cut some 5" x 2" heatsinks on my tablesaw once without issues. It helps to have a sliding table and a non-ferrous blade. That is my current setup. If you are just cutting them in half lengthwise, the original finished side can stay on top, without much loss in appearance if you don't look at the bottom of the amp.

--
Brian
 

BrianGT

Retired diyAudio Moderator
2002-01-21 2:42 pm
near Atlanta, GA
www.chipamp.com
Here are some of the chassis that I have made for Class A amps, but never finished...

The smaller one in the front is made from cutting one of the bigger black ones in 1/2. I bought these with Rob and his chassis is made with 5 heatsinks.

(aluminum not finished yet.. needs some work to get the scratches out. I built 2 of the large ones with surplus heatsinks, originally for Aleph 2 monoblocks)

--
Brian
 

Attachments

  • chassis.jpg
    chassis.jpg
    90.4 KB · Views: 948
gengis said:
kestrel200,

Try a vertical metal band saw with some hard plastic (polyurethane, or..) on each side before the clamp to protect the finish. The band saw will have thinner kerf and should not bend the fins if cut from the base side.


Unfortunatley I don't have a band saw:xeye: So I'll have to figure out the best way to do it with my table saw.
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.