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For Sale Large Heatsinks for Class A projects

Things you have for sale.
I have realized that it is unlikely that I will be as active in this hobby as I once was, so will start listing parts for sale here in the coming weeks. First up is my collection of large heatsinks that I collected for Class A projects but never used. I'm sure I paid too much for some of these, so will probably end up selling at a loss despite increases in metal prices, but such is life.

PayPal is probably easiest for payment. Will ship within the US at buyer's expense; contact me with your ZIP code for a quote. Will consider shipping to other countries, but shipping may be prohibitively expensive. Local pickup in western Illinois is also a possibility, as is meeting part way of schedules line up to allow travel.


Lot #1: pair of silver heatsinks which do not appear to be anodized. The bases look polished, and the fins are maybe oxidized aluminum instead of anodized. Fins are "serrated" for increased surface area and better dissipation. Some holes drilled and tapped in base. Each sink measures about 10.25" wide, 9.875" high, 3.125" deep, with a 0.625" thick base, so the fins are about 2.5" tall. Each sink weighs about 13 pounds. Each sink has small cutouts at the bottom of a few fins as shown in pictures. These were very expensive when I bought them because of their size and weight. Asking $75 for the pair. SOLD

Lot #2: pair of black anodized heatsinks which appear to have been salvaged from an amplifier chassis. These have some channels cut in the top and bottom for mounting. Some holes drilled and tapped in base and some scuffs in the anodizing. Each sink measures about 10.25" wide, 8.125" high, 2.625" deep, with a 0.625" thick base, so the fins are about 2" tall. Each sink weighs about 11 pounds. Asking $65 for the pair. SOLD

Lot #3: pair of clear anodized heatsinks which have done holes drilled and tapped all the way through the base and fins. Good shape overall with the odd dent or scratch here and there. Each sink measures about 9.75" wide, 9.875" high, 2.25" deep, with a 0.25" thick base, so the fins are 2" tall. Each sink weighs about 5 pounds. Asking $35 for the pair. SOLD

Lot #4: three black anodized heatsinks which have a grid of holes drilled and tapped in the base. Some scuffs and fins on the sinks. Each sink measures about 7.875" wide, 5.875" high, 1.5" deep with a 0.375" thick base, so the fins are about 1.125" tall. Each sink weighs about 3.5 pounds. Asking $25 for all three.SOLD

Please see pictures in subsequent posts for details about each lot. Note that measurements are rounded to the nearest 0.125" for simplicity and weights are approximate as my scale's accuracy is questionable.
 
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Pictures of heatsinks in lot #1.
 

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For Class A amp heatsinks, I use inverter heatsink. If you have any electrical friend who has a damaged inverter, you can take those large heatsinks from inside.
It costs free to very few dollars, depending on your friendly electrician.
A 3.7 kw inverter heatsink will dissipate about 6% of the rating, to keep the temperature of power devices at 60 deg C. (3700 x .06 = about 200 watts cont.)
Some models use forced cooling with a tiny fan over the heatsink.
Choose a size that fits your project.

Regards.
 
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I have confirmed that all heatsink lots can be shipped in USPS Priority Mail flat rate boxes, so shipping is not the huge expense it might otherwise be. Lots 1 and 2 fit in a large flat rate box, so can ship at $22.80, while lots 3 and 4 fit in medium boxes which ship at $17.10.
 
Lots 1 and 2 sold. Prices adjusted again on lots 3 and 4. Shipping is $17.10 for either lot, in a medium flat rate Priority Mail box by USPS.

I used the heatsinks in lot 3 for a bit to cool an Aleph 30 style amp, so they can take a decent amount of heat despite the lower mass compared with lots 1 and 2. Lot 3 is great for smaller Class A (up to 30W or so dissipation, such as for an Aleph mini, which I built using these sinks) or medium Class AB circuits. Lot 3 is also great for prototyping because of the array of pre-drilled holes.