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Brians256 · 01-13-2003, 01:27 PM

I know very little about how to PROPERLY lap a metal surface, so I'd like a better understanding of how to do it right.

What I've been doing is using sandpaper that is taped to a granite block (a reference block used at work to planarize chuck surfaces and other mechanical pieces for semiconductor equip). The granite block itself is very flat, but there is a certain amount of flex in the sandpaper as I apply pressure when lapping. Also, even with a figure-eight motion, I get rounding on the edges. I know that the block is fairly flat, since I can lift plate glass with a wet block (surface tension of water). But, I don't know if there is a better way.

Perhaps I'm blowing all this out of proportion, since only the central 3/4" square needs to be coplanar with the CPU on an AMD cooling solution.

01-13-2003, 01:27 PM	#34
Brians256 Pro/Staff Join Date: Oct 2001 Location: Klamath Falls, OR Posts: 1,439	I know very little about how to PROPERLY lap a metal surface, so I'd like a better understanding of how to do it right. What I've been doing is using sandpaper that is taped to a granite block (a reference block used at work to planarize chuck surfaces and other mechanical pieces for semiconductor equip). The granite block itself is very flat, but there is a certain amount of flex in the sandpaper as I apply pressure when lapping. Also, even with a figure-eight motion, I get rounding on the edges. I know that the block is fairly flat, since I can lift plate glass with a wet block (surface tension of water). But, I don't know if there is a better way. Perhaps I'm blowing all this out of proportion, since only the central 3/4" square needs to be coplanar with the CPU on an AMD cooling solution.