Thread: Naniwa Bulge

I think that the size of what you use to lap the stone makes a diference. If the stone is around the same size as the lapping surface, there's a tendency to overshoot the lapping plate on each stroke and at each end. At first I thought that this would result in the middle being hollowed-out, but found that the middle was raised. I suspect the andle of lapping or the pressure used changes on the overhang. Lapping a 1000 grit on a DMT about the same size as the hone first showed up the problem for me, as this hone laps very quickly. Changing the DMT for a large sheet of sandpaper laid on a flat glass plate removed the bulge in the middle of the hone. The hone never went past the edge of the paper. Maybe it's also the pressure I was using at the time - I know that you should just let the stone work under its own weight or thereabouts, but always being in a hurry I probably "assisted" too much! Maybe something like this has happened to you?

Regards,
Neil