09-03-2017, 11:00 PM
My theory (more speculation than theory, really, as I don't have either the knowledge or data to support it) is that it has more to do with the geometry than anything else. I can get a plane blade at 25 degrees inclusive angle to BESS 100 consistently, but haven't been able to get a knife at 20 dps below 150. I doubt it's the steel, as I've sharpened both carbon steel and high RC (62) plane blades, and low RC (57~58) and high RC (62~65) knives. I wish I had enough steel and time to do some real tests. My guess is that both the apex angle and the thickness of the blade just behind the edge are the biggest factors, assuming no burr remains.