Lapping a heatsink?

[Nate Finch]

Exactly how does one "lap" a heatsink, and what kind of concrete thermal benefits does it give? I have a Thermalright XP-90C that I just received, and the base looks fairly good, but no where near a mirror finish. How would I go about getting that mirror finish (preferably with stuff you can get at home depot), and how much of a difference in temperature should I expect?

-Nate

 

[_Korruption_]

I would much rather prefer a flat base over a mirror-finish. Thermalright is typically pretty good with ensuring base flatness. If you lap the base incorrectly, your temperatures will be negatively affected. Don't bother.

 

[=lks= ka druma]

to add to that.

Use google. And don't go to home depot, go to autozone or your equivalent autoparts place. They sell 3M wet/dry sand paper upto 2000 grit. Most of the time you can find a 4 sheet packet with sample of every grit 400-1000.

But yeah man why lap a +$50 HS thats silly.

 

[Borgschulze]

to add to that.

Use google. And don't go to home depot, go to autozone or your equivalent autoparts place. They sell 3M wet/dry sand paper upto 2000 grit. Most of the time you can find a 4 sheet packet with sample of every grit 400-1000.

But yeah man why lap a +$50 HS thats silly.

For the mirror finish duh

 

[Nate Finch]

For the mirror finish duh

...which you then smear with Arctic Silver and squish onto your CPU. Sweet.

Thanks for the tips guys! I'd rather not bother lapping it if I don't have to, and it sounds like I don't

-Nate

 

[Mad Machinist]

By definition the way I see lapping described in these forums is ludicrious.....in the machine world, lapping is done to achieve precision fit......the same thing you are attempting to do with processors and heatsinks. When attempting to achieve a flat surface by lapping you use compound and actually apply the surfaces to be mated to each other...to produce true precision surfaces you actually use three surfaces constantly rotating them...sanding dosen't necessarily produce a flat surface......try lapping a heatsink with sand paper.......and then coat it with prussian blue and check it agains a precision surface plate. You'll be amazed how far from flat it really is.

 

[AuroraProject]

By definition the way I see lapping described in these forums is ludicrious.....in the machine world, lapping is done to achieve precision fit......the same thing you are attempting to do with processors and heatsinks. When attempting to achieve a flat surface by lapping you use compound and actually apply the surfaces to be mated to each other...to produce true precision surfaces you actually use three surfaces constantly rotating them...sanding dosen't necessarily produce a flat surface......try lapping a heatsink with sand paper.......and then coat it with prussian blue and check it agains a precision surface plate. You'll be amazed how far from flat it really is.

Sshhhhh! You're introducing reality to the discussion.