C Section Purlongs used as heat sinks

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as i had some 52mm x 150mm "C" Sections laying around i decided to see if i could used them to make heat sinks for my amplifier project.

i decided to build a john Hood 10W class A amplifier and found that if i used a piece of "C" Section 800mm long with 6 2N3055 transistors evenly space the transistor case temp only got to 45 degrees C in a room with a temp of 25 degrees C

this was with a supply voltage of 28volts and the current set to 1.4amps

from this i plan to build a amplifier using "C" Section stanging up back to back to form a towel giving the amp a different look
to save money, what else have you been using for heat sinks on your projects.

Also "C" Section allow you to build cheap strong amplifier cases, as all you have to do is join 4 pieces of "C" Section to the size you want cut at 45 degrees with right angle brackets, screw a flat piece of metal on the top and bottom and you have you case.
you can get 50mm x 75mm "C" section.
you can get 52mm x 150mm section or bigger.

i only paid $3 a metre second hand for my 52mm x 150mm, so i can build my Amplifier case for around $20 and it's alot stronger than the cases you buy from suppliers.
Paint it black and add a Aluminum front and your done, easy!


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This is really interesting John...but...i am sorry to say, that i am afraid

That the heat conduction speed.... heat transference speed, is not so good, as this kind of aluminium, called duraluminiun, hard aluminium, is a result of metal mixing to improove mechanical resistance.

You will perceive that you will have hot point around transistor, and cold points distant of it.

Resulting a not so good heatsink.

Despite of that, i had used it many times...this is diy, the spirit!, and i think was interesting you publish that.


Hello Distroyer X,
even worst, the stuff is made from steel not aluminum.
I have run my JLH CLass A 10watt Amp for hours and the temp stayed the same?
One thing for why it might have worked was that i was powering the amp with 28volt rails and not 40volts as is the norm.
same ampage levels 1.3amps.
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