Engineering Question: How To Measure Sharpness
I want to measure the sharpness of a razor blade, for reasons. I have two ideas so far:
- Spring based force measurement device that somehow is attached to weights or the razor blade and pushes the blade into rayon thread. Jot down the number of Newtons, or whatever, it takes to finally slice through that thread. The lower the force required, the sharper the blade.
- Use a printer to push paper in to a clamped blade and under a microscope see how clean the cut was on the paper. Sadly this does not result with a number, which would be more ideal.
Neither of these ideas are great. #1 is bad because it would be hard to use for comparing different blades. I would need to apply the exact same amount of force, in the exact same increments, and keep blade/thread at the same angle. It's not a realistic experiment without precision machining. Meanwhile, the printer idea although easy to setup for consistency, does not provide a numeric outcome.
So ... I am wondering if any of you actual engineer/science people have thoughts on this.