I finnaly have the cap off my K6 [email protected], PITA. I laped the HSF, of course good size base, BUT how the heck do you do the core and keep it flat? I used a piece of glass under the paper, had my finger in the center, and the edges seem to be rounded now. When I put a razor blade on it it rocks around , not flat. HMM TIA!! I must be doing somthing wrong.