Thread: A Proper Studt of Sharpness With All the Data

i didn't get that far into the video before thinking "i don't know what obsidian would do but everyone I've ever seen knap it never got anything useful out of it" and "I and everyone else here could sharpen an edge that would split a hair down the center easily. The challenge would be holding it.

The test that they've setup is gamed - the hair section is short and the hair is fed directly into the edge. What you'd have issue with with a very sharp edge is if you tried to feed a hair into it, you'd have no way of controlling the cut so that the edge didn't just leave the side of the hair at some point due to inaccuracy pushing it.

when I see people talking about the string test or wire test and taking one measurement off of an edge and then declaring they know something useful for woodworking, it makes me shake my head. the test of sharpness for woodworking would be two pronged - first the initial sharpness and the actual resistance to a cutting edge, and then a curve on the edge measuring various forces.

the guy's last statement was the most useful part of this, but people won't grasp it until they make something really sharp by a test standard and find it doesn't work that well for what they're doing. No industry is going to set up tens of millions of dollars worth of production or something where edges are used based on a "Wire test".

(I well sharpened straight razor will catch and sever a hair under its own weight on both sides of the edge, without gripping close to the cutting point to make the hair stiff. Even that test is affected by the thinness/stiffness of a razor's edge).