Thread: How does Lapping actually work?

The question was “How can you lap a 10,000 grit stone with a 250/400 grit sandpaper, and not have a bunch of scratches in it?” the scratches don’t matter as long as the scratches run parallel to the honing direction. It becomes a matter of aesthetics removing scratches on a hone. Lapping a stone to 8K is a waste of time, effort and 2 stones. Unless it increases performance and you will not know that unless you experiment with that stone.

Flat is a relative term, we are attempting, 1.to get the tops of most of the grit on the same plane, not all the grit. 2. Refract the grit. And 3.Unload/clog the grit, all at the same time.



Attached is a stone I pulled from the slow cooker it’s been soaking for a few days, I suspect/hope it may be a coti… maybe an old ark. It was somewhat yellow when it went into the soup.

Now I could flatten the dished side, it would be purely aesthetics, a waste of time, sandpaper and effort. Instead I will lap the bottom side and test for its cutting/finishing abilities. If you could lap the dished side so all the grit is at the same height and you held the spine on the hone you could sharpen on the dish side of the hone. How does a jointer/surface planer flatten a piece of wood? The cutter head is round, and the blades travel in a circular motion, no?

Many times we do thing just because others say to without asking why? I applaud Clarence for asking why? Get as much information, then do what he thinks is best for him, experiment and see what works. To blindly polish rocks to a mirror finish, just because… is not productive or skill building. Now that is silly.

How many threads have we read from novice honers who have done x laps on 1K-12k as instructed and can’t get a razor to shave? Was it sharp at 1K? No one ever checked, but he did the required laps.
We are not baking cakes.