[plug] [OT] Tech rant

[Kev]

James Devenish wrote:

> Urgh. What an ugly sentence. What I meant to say was: I would have
> thought that picking up any old black paint and applying it to your
> heatsink would do far more harm than good. For one, you will first need
> to find a paint that is black at infra-red frequencies, not at optical
> frequencies. Also, an efficient unpainted black anodised heatsink looks
> black for reasons that have nothing to do with paint. The anodisation
> should produce a pitted surface, not a smooth surface, and this should
> theoretically enhance the heat dissipation in a far more significant way
> than attempting to apply any layer of paint. Also, you would want paint
> that is thermally conductive, not paint that is mildly insulative.

The paint applied to a properly cleaned surface (NOT applied with a 
chooks foot dipped in tar) is in intimate contact with said surface, 
providing near as good a thermal conduction as is practicable in the 
home.  Bear in mind that I did say matte black paint.  This WILL give a 
measureable decrease in operating temperature.  Why do you think it's 
done to high performance engines?  As for me, here at home, I played 
with it and looked at the effects, and I just used Dulux matte black 
spray enamel (spray can that is).  If you already have a black anodised 
heat sink then all the better, don't paint it.  Most of us have various 
colour heat sinks - anything except black in my case (no pun intended).

Cheers
Kev