I’ve been exploring different types of precision abrasives for lapping and surface finishing applications, and it’s surprising how much the results can vary depending on grit type and particle consistency.
From my experience, the choice between alumina and silicon carbide often comes down to balancing surface finish quality with removal rate. The right abrasive type and progression can significantly reduce subsurface damage and improve overall flatness.
Curious to know what others here prefer — do you stick with conventional abrasives, or have you shifted to diamond-based options for high-precision finishing work?
I believe they use diamond paste with 50-60,000 grit…
1 Like
50–60k diamond can work very well for the final stage, especially when the goal is to remove the last fine scratches rather than achieve significant material removal. The surface condition going into that stage is probably just as important as the final grit.
Have you found a particular lap or carrier works better with the finer diamond?
I prefer the 100,000 diamond for a final finish. Depending on material hardness the stage before the 100k diamond is either 8k diamond or 13k diamond for softer than moths hardness 6 sometimes 7 at the most. The 8k is my prepolish on harder than 7 stones before the 100k diamond. On certain materials I will use a cerium oxide slurry. Usually on 7 hardness material like Quartz. I have several 50-60k polishing laps also but I use those for quick commercial cuts instead of the ultimate quality and precision of custom cuts.
1 Like