Testing a Few Questions

If you can borrow or buy a copy, Leonard Lee's book The Complete Guide to Sharpening has some good micrographs of chisel edges. I hear that John Juranich's book has some micrographs as well, but haven't read it yet.

The Verhoeven paper has a lot of info stuffed into it, though it only focuses on removing burrs to leave a very fine edge, sometimes down to < 0.2 microns. The comparison standards he used are a Gillette razor blade and a straight razor, so his emphasis is clearly on as fine an edge as possible.
 
Some more info on the chipping. It appears I have hit an area of steel with small round inclusions. I sharpened out the nicks last night and took the edge down to a 1000x waterstone finish, and there are new spots on the side of the blade, which will eventually meet the edge. I had all the nicks ground out but one, and now there are about 5 new ones that developed during sharpening. Food Network knife users, beware, though this really doesnt bother me much for kitchen use.
 
An update related to my original intent. Since the FN knife developed nicks, had them removed, and developed more, I took it to the belt sander after removing most of the nicks on the 220 grit stone. There was a large flat on the edge, also indicating that the old steel from the steeling experiments was gone.

I cut a new 20 degree per side bevel on a worn 180 grit belt. The wire edge was only visible in a few spots on the blade. Then I removed it using a leather belt on the sander and 3 or 4 stropping passes per side. After this, it would shave above the skin.

I then redid the edge flex test, which the knife passed. I flexed the edge on a round screwdriver shaft and looked for deflection. Afterward, the edge returned to the original position and the knife checked for nicks or drags with a thumbnail; none were found that weren't there before.

After this, I tried cutting bread ties on a plastic cutting board. There was no detectable chipping after this test either.

So at least for this knife and these 2 tests, no difference was found between sharpening by hand and sharpening on the belt sander. I suppose I could do edge retention tests, but that original batch of cardboard is gone, so it would be difficult to compare. That and I lost count of how much I'd cut and it would still shave after a touch up on my "steel".
 
i use cardboard to knock off the burr when i sharpen mine...it is abrasive to a extent..i know some guys that rub a green buffing compound on the cardboard.... the steel thing is just pushing the edge back to straight if you could imagine the edge of the knife rolling off to one side or another
 
I discounted steeling for a long time. I still think a fine ceramic or diamond steel is better, but steeling works, no doubt. I tried cardboard with and w/o compound but haven't had much luck. I need to get a couple of the same knife and compare edge holding after sharpening on by hand and the other on the belt sander. So far, the tests I've done show no difference. That was the original intent of this thread, but I got way sidetracked when I started steeling the edge.
 
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