Our Grit Selection Chart

We have chosen to use effective (or actual) micron grit size as the scale by which we can compare the effective fineness of stones, understanding that particle size alone is not the only determinant of finish. Factors such as grit shape, bonding material and grit durability can all influence effective fineness. We charted five grit standards using micron grit sizes from 4125μ, down to 0.3μ, and added Shapton stones, ceramic stones, water stones, diamond stones, oil stones and specialized sheet abrasives to create a table of relative fineness.

Moving from a damaged edge to an ultimate edge involves four stages of sharpening:

1. Shaping: establishing the basic profile of the tool, usually required only after major damage
2. Grinding: establishing the geometry that defines the edge – bevels and relief
3. Honing: preparing the blade for use
4. Polishing: imparting a keener edge to a honed blade

We divided our chart into grit ranges appropriate for each sharpening stage, with the last three ranges split into three subranges (low, medium and high, designated by letters A, B and C). Grouping them together in micron-sizebased bands reduces the complexity of comparing different products. Conceptually, it makes selecting a sharpening solution for each stage easy while choosing abrasive solutions that complement what you may already own. A good general rule is that for each sharpening stage, you want to move from one range to the next, keeping two or more divisions difference between steps.