Hi,
I began lapping the back of a plane blade for a wooden jointer plane that I recently purchased. I have the back flat, I just need to get through some pitting at the edge. Now that the back has an even scratch pattern across the back, I noticed that there is a small margin around the edges of the back that are very shiny colored steel, and a patch in the center of the back that is of a slightly duller color, what does this mean?
Christian