lapping a heavy heatsink

[JohnnyLucky]

When lapping a large heavy heatsink like a Thermalright Ultra 120 how do you keep the heatsink from rocking back and forth? I'm trying very hard to keep the heatsink level but it wants to rock.

 

[eklipz330]

umm you might want to try a vice grip or something... holding it won;t do

try wedging it between two heavy objects, tie it down or something, don't hold it

 

[JohnnyLucky]

I thought about it but couldn't recall any posts about the problem. I kept thinking I'd have the same problem if I clamped down the heatsink and used a sanding block.

I just finished and I think I'm okay. I guess I got lucky. I used two different types of razor blades and a bright light to check for flatness before, during, and after lapping. The edges needed the most sanding. Just had to be careful and stop before I went too far. The cpu was a lot easier to lap.