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Whats the Highest "Grit" sandpaper you have ever lapped you HSF with

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Senior Lighting Designer
May 2, 2001
I finished off with 4000 Grit jewelers sandpaper.
I started out with 800 and finished off with 1500 W/D,left a pretty mirrored surface on the hs.Use water with the sp also.
i have lapped some no name brand hsf with 300 and finished with 600 i didnt spend more than 5 minits doing it and i brought down the temps of a t-bird 900 from 38 idle 31 and under full load it never goes over 48 so it made a big difference and i didnt have to work too hard
cold mop (Jun 18, 2001 03:48 p.m.):
toothpaste, it's pretty fine

Have you actually tryed that or are you just presuming that because it's an abrasive it would work as I have tryed regular toothpaste and it didn't get my heatsink white enough :D
No I'm kidding, I tryed it and it just didn't work as it was really gunky. Smokers tooth paste powder may work which I'll try tomorrow.
I thought it was discussed somewhere that too smooth of a finish degrades heat transfer.

A less than perfect finish /\/\/\/\/\/\/\/\/\/\/\ gives thermal paste a place to flow and allows the points to make contact with the surface to be cooled.

A more perfect smooth finish ========== will float on the thermal paste and have less contact with the surface to be cooled.

I may have read that in one of the articles posted here at Overclockers.com.
Plus when I take my heatsink off most of the Artic Silver has been pushed out and there is only small amounts in very thin patches. No thermal compound offers as much heat transfer abilities as a heatsink so the less you have to use the better which is why I disagree for leaving troffs for it to go into. With the small size of the die on coppermines and durons/tbirds the excess is squished out quite easily and with a bit of wiggling and then running without the fan on for a short period of time which seemed to lower my temps, the get a very good heat transfer.
Cut him some slack Phil. We all know he meant Crocus cloth. For those of you who are unfamiliar with the term, it is a sheet of stiff cloth with ruby dust bonded to it. As an abrasive, it's useless for removing large amounts of metal, as it clogs too fast, but it is an excellent polishing material. Kind of like dried Brasso on a cloth. Unlike Brasso, the harder the material being polished, the better it does. This stuff will polish glass, chromium, virtually anything. I get mine from the local hardware store for $1.00 a sheet. Some carry it, some don't.
Personally, I feel anything past 1000 is overkill, especially if that 1000 was administered with soapy water as the wetting medium.

2000 grit, although I had accsess to a perfectly flat surface on which to do it on, and the measuring tools to verify that the heatsink was still flat to 100 000 of and inch, afterwards. I also used rubbing compound (3M finishing compound) after sanding to further polish it. I might take the HS off and re-lap it, with a heavy grade (1000 grit), to see if it really makes a difference, going past 1000. If and when I do, I'll post my results.
hey where is my toothpaste response..posted a while ago

yea I use it all the time for stuff. used it yesterday for taking the oxidation off a waterblock. Best is saving scratched CD's with it though
220 -> 320 -> 400 -> 600 -> done. not polished, but definitely flat. No temps yet as I've not turned it on yet.

Mirror reflection - not necessary, and definitely not the objective.
You just want it flat.

I used 2000 as my final grit when I lapped my both of my HSFs, but I've come to realize it's not really necessary.