I understand about abrasive resistance and heat treating.
What I want to do is compare something like a cannon ball to a spear point, regardless of heat treating or type of steel. The cutting tool, regardless of material, might only be required to make one cut or shave one hair.
I want to know how sharp it has to be to make that one cut or to shave one hair. It doesen't matter what type of steel it is, or how it is heattreated. It could be aluminum, copper, brass, or even sliver of glass. Edge holding is not in consideration here.
For example, a cannon ball of 01 steel at RC 60 would hold a better edge than a bronze pointed spear, but the cannon ball would not cut as well. For a time, anyway.
I hope this explains what I am asking, like what is sharp and what is really sharp, and what is extremely sharp, and how much difference there is between sharp and extremely sharp, and how to measure the actual width of the cutting edge at it's finest point.
