can you imagine if the conventional wisdom for judging size-tolerance of fabricated-materials was along the lines of, "how does it feel when i shave hairs on my arm?"
I want to _measure_ knife sharpness. In a repeatible, scientific way. And preferably, non-destructive to the sharpened edge!
the floor is open for discussion.
The experience of razor blade makers may be instructive.
[I dramatized the story...]Once upon a time, the King announced a competition for razor blades that were to be the sharpest obtainable.
The leading cutler in the realm entered two batches of his best blades.
The King pondered the many entries, and settled on one of the two batches made by the famous cutler. The prize being awarded, the King returned the remnants of both batches, remarking that he wanted no more of batch a type, and all of batch b.
So the cutler examined the quality records, and noted both batches should have been identical. What could be the difference?
Under the medieval microscope, the batch a blades were of unparalleled sharpness, and were verified as durable. Very puzzling.
Then, looking at the successful type b blades, the maker noticed a fine ragged pattern on what should have been the same fine edge. He realised this was the same effect that he had been rejecting blades for, when the stropping machine went wrong and created saw teeth in miniature on the blades.
So then, he set the machine for this effect, and rejected any blades that came out too fine and smooth. And everyone lived happily, ever after.
Brian Whatcott Altus OK
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