[SilverCans]

Is it ok to spray my heat sinks with BBQ grill spray paint? Will it reduce the thermal effectiveness of the heat sink? I sort scratched them up when drilling holes in them and would like to repaint all surfaces except where the transistors mount.

 

[rickcr42]

You can tough up heat sink scratches with a black felt tip pen.Not the fine point whimpy but the fat honkers for marking BIG things

 

[SDA]

Probably, yes. Paint is much less thermally conductive than aluminum or copper, and having that between the heatsink and the air could be an issue. Why bother?

 

[mono]

It would reduce cooling effectiveness.

What I might try is thoroughly cleaning the scratched area, then putting a full-strength bleach - soaked cloth on the areas to hold a puddle of bleach over the scratched area for awhile to grow an oxide layer on it (but not TOO long) then that more-porous oxidized layer will better absorb black dye or black marker.

If you go with a marker for color you might consider a laquer-based marker like a Sharpie "Industrial" type, available at some office superstores, maybe Staples or Office Depot, Officemax, etc, in the US.

 

[Garbz]

If you have some spare $$$ in your pillow you could always go out and get them anodized black

 

[mono]

I suspect new heatsink would cost less than re-anodizing current 'sink.

 

[CPL593H]

The best touch up is flat black paint, put it in the scratch with a toothpick and lightly wipe off the excess after a minute. You'll get it right after a few tries. Just wipe it all off completely and start over if it doesn't look right after the first try.

 

[bryman79]

What is the heatsink coated with? If it's anodized, don't paint the whole thing since the paint won't stick well. I'd prefer a scratch touched up with either sharpie or paint over anodizing showing through flaking paint.

Regards,
Bryan

 

[Emon]

You have a few feasible options:

1. Re-anodize it yourself. Actually not that hard, do some Googling, but be careful. Toxic chemicals and high currents are involved if I recall correctly. Dying is done with RIT fabric dye usually.

2. Use a felt tipped pen to fill in the scratches. Pull it back a few feet and you'll barely see them.

3. Leave it how it is. Unless you have a window in your device (amp?) no one's going to see it, and anodizing just makes a protective layer of aluminum oxide over the surface via corrosion. It won't corrode through if you don't anodize it. It's mainly for aesthetics, especially in such low end applications.