3 micron diamond grit: 20 minutes, 20 lbs, 120 rpm., dispenser at 1 or 2.
0.3 micron diamond grit, 10 minutes, 15 lbs, 120 rpm, dispenser at 2.
Start section at 5 lbs pressure (minimum). After holder is pressed to the platten, raise pressure to the recommended value.
Alternative: 0.3 micron alpha-Al2O3 grit, suspended in deionized water of Buhler's grit extending solution. Use 15 lbs pressure for 10 minutes, then 5 lbs for 5 minutes. No, I don't know why Al2O3 cuts so fast.
Lap surfaces should be the Texmet 2500 non-woven fabric disks. These result in less surface topography than the softer Texmet 1500 or woven fabric surfaces.
Thin section should be secured onto the thin section holder with a piece of double stick carpet tape about 1/4" by 3/4"; 6 by 20 mm, with the tape centered on the rock area rather than the glass.
This is a photo of the back of a Buehler flat, blank sample holder. As-is, it can't hold any samples, but see below. The Buehler part number of the whole assembly (black disk plus stainless steel fitting) is 602408. If you have a machine shop, you can make your own disk and just buy the stainless steel fitting, part 602499. Here are plans for the disk.
I have tried numerous methods of holding thin sections in the holder. This is the best so far. Cut a circle of adhesive-backed rubber sheeting, 1/16" thick (about 1.5 mm). Put it on the clean disk bottom, and bevel the edges with a new razor blade. Then cut a thin section-shaped hole through the rubber, with extra space for corners (important). Glue in a spacer (I used a piece of plastic ruler) to make sure the thin section surface extends slightly beyond the rubber. The thin section is held in place initially by double-stick tape, as mentioned above. Take the tape into account when chosing a spacer. Self-adhesive rubber sheet can be obtained from many places. Yes, I have tried similar setups with multiple thin sections, but that has always resulted in an uneven polish. Let me know if you find something that works better!