03-23-2017, 04:55 PM
Jim is an absolute expert with a KN100 and an excellent example of the accuracy that can be "wrung out" of this instrument in practiced and experienced hands. As Jim says +/- 20 is an excellent result for most sharpeners. This would mean that the total variation in apex width along the apex of the edge was something on the order of 40nm - an incredibly small differential but still achievable by many sharpeners. Variations in measurements along the edge will be both a function of the skill of the sharpener and the roughness or "tooth" of the edge.