As a young lad following my grandfather around, he taught me that all that was necessary to check the edge of a knife was to hold it in such a way as to get it to reflect light from any source. His words were,"A keen edge reflects no light". This metheod has worked well for me for many years now, and I trust it without question. If you're looking at any "edge" and you can see light reflecting off of it, it is not sharp. It is possible that it may feel sharp, but I trust my eyes more than my sense of touch. Works for me. Of course, if you need to verify the accuracy of a cutting profile, then a comparator or similar device is needed, but if you are confident of the profile, then nothing beats the human eye.
Last edited by Ed Tipton; 12-08-2006 at 05:58 PM.
There is no shortage of experts, the trick is knowing which one to listen to!