Craft & Design
The Heatsink from hell

Jschuch writes “So, the title of the eBay auction was “large rectifier”, and sure enough the photo showed a couple of what appeared to be large heatsinks with stud diodes inbetween them. Opening bid was $0.99, and the seller is near my house (a clearance business that moves thousands of ebay lots per day) so I wouldn’t have to pay shipping. I bid $1.00, and won it. I went to pick it and a dozen other lots up last friday. The girl rolled out my other lots and asked if I’d mind going back in their warehouse and getting the rectifier myself. Well, I could lift it, but i couldn’t carry it any distance!! To make a long story short, the thing is about 4 times as large as I guessed looking at the pictures. It’s about 18″ by 12″ by 10, and easily weighs in around a hundred pounds! So, the question is: I have no earthly use for the thing, and while turning a $1 ebay lot into $58 at the aluminium scrap yard is an attractive option, I’d hate to see the thing melted down when there may be someone out there that could use it. Any ideas?”Link.

Post up suggestions in the MAKE forums! – Link.

36 thoughts on “The Heatsink from hell

  1. Is it really hard or really easy to melt down a heatsink? I figure it would have everything to do with whether there is molten aluminum or just a dry, hot surface, but I’m not sure.

  2. Suggestions:

    1. Bolt that thing onto a hemi.

    2. Use it as a stand for a Mac Book Pro (I kid – I’m typing this on one right now.)

  3. Time to start doing experiments on Tesla Coils…. build a 4.6 Megawatt power supply and start making lightning :)

  4. The sides look like they’re symmetrical, if you take it apart, the top and the bottom look like they’ the same size.

    If you hacksaw the x-section and make smaller slices, you could turn it into several cool looking CD stand..

    Maybe you could take it apart lie it upside down to hold your bowling balls. (if you’re a bowler)

    I like the steak idea.. (-:

    Connect heat packs to the back of one of those sides and turn it into a silent space heater – well, fans might help, but I think 400 watt, or 500 watt (which this thing will easily dissipate) would be good for a small dorm room – and it’ll look cool. It shouldn’t get hot enough to burn you if you touch it at that low wattage.

  5. Class A audio power amps require a LOT of cooling. You can either build one yourself or sell it to an audio nut who is building one. Audio nuts will pay top dollar for anything. Go over to and post a notice on their trading post forum.


  6. Is it aluminum? Do you have any idea what 100 lbs of aluminum is worth… jeez man. Take that thing to a local scrapyard and walk away with a couple hundred bucks at least.

  7. Is it aluminum? Do you have any idea what 100 lbs of aluminum is worth… jeez man. Take that thing to a local scrapyard and walk away with a couple hundred bucks at least.

  8. Is it really hard or really easy to melt down a heatsink?

    It should be really easy to melt a heat sink. The same extra surface area that lets it radiate heat quickly also makes it absorb heat quickly. Compared with a comparable solid block of aluminum, this would melt much quicker.

  9. I second the table idea: fasten a glass plate to the top and you’d have yourself one hell of a coffee table.

  10. I guess whether this thing would melt faster than a solid block would depend on the surrounding temp…

    If the ambient temp is lower…then the larger surface area would allow it to radiate the heat to the surrounding air. If the heat is not “retained” as I would assumed that is the whole point of a good heat dissipator…it should take longer than a solid block to melt?

    However… I guess this thing would melt FASTER if it is in an oven…since the ambient temp would be high and the larger surface area would absorb the heat faster.

    It early and I’ve not had my coffee yet…so this may all be crap :-)

  11. The average scrap value of aluminum in the USA for March 2006 was 87 cents a pound. Generally scrap yards will pay you half of that because they still have to haul it to a regional recycling center and make a buck for the labor.

    A really cool project would be to somehow use this thing as a Mountain Dew cooler in the winter. Just set it outside and circulate some antifreeze through a loop out the window and back into your armchair beverage holder. A table would be cool too.

  12. I would be tempted to bolt it on top of a CPU. It would have to be one of those all in one motherboards. Still, it would get a lot of looks, and you would not need a fan.

    The other thing would be to use it for the hot side of one or more pelter devices. I have this idea of sitting two pieces of PVC coaxeally, with expansion foam between them on top of the cold side, making a chamber just big enough to hold one 12 oz can of beverage. Run the thing off the +12V supply in your PC.

Comments are closed.


current: @adafruit - previous: MAKE, popular science, hackaday, engadget, fallon, braincraft ... howtoons, 2600...

View more articles by Phillip Torrone