I little advice for lapping with the DMT. Sharpen a couple of knives with it before you lap the Naniwa. New DMTs can have high spots that can put deep scratches in a soft Naniwa. Sharpening a couple of knives will knock the high spots off. Some say you don't have to soak Naniwas but I disagree. They swell slightly in the center and will stabilize after soaking for a few minutes.