Quote Originally Posted by mainaman View Post
What is SEM? and why would you need one to be able to tell if the razor is shave ready or you need to hone it more?
You do not need to see the edge to know when you are ready to move to the next grit. All it takes is to hone a decent amount of razors and observe scratch patterns and color characteristics of the bevels and close to the edge. With time one can develop a correlation of what the bevel looks like and how the shave will feel.
SEM = Scanning Electron Microscope...

For me the ultimate test is whether or not a razor can tree top my arm hair. I have very fine arm hair and if a razor can tree top my hair I know it's as sharp as it will get.

I think the point is that sharpness does not always equate to shave ready - a razor may not pass various objective tests and still shave great.

-john