3-finger test

[napaknives]

Welcome to the forum, Dan.

First, I would trust the BESS numbers.  160 – 230 is a nice, very sharp blade.  You can’t get numbers like that unless the blade is sharp.  I suspect that it shaves hair, cuts paper, hangs on your fingernail and passes all the other subjective tests methods without any problem.
 
People have dreamed up all sorts of ways of testing sharpness, and there are advantages/disadvantages with each.  I don't think there is a right or wrong way, but that it's really a matter of personal experience and preference.  You know; whatever works.  

Personally however, and this is just my humble opinion, I think there are some safety concerns with the three finger test.  It may work just fine for experienced folks, but it sure seems a little risky.  I know from (stupid) personal experience that a razor blade has a slightly almost sticky kind of feel, and then shortly after that you start bleeding.  I’ll feel a blade by gently pulling my finger perpendicularly with a slightly down angle across the blade, but never slide my finger along the edge.  Yikes!
 
Additionally, the three finger test would seem to be extremely subjective, and at the very least would require a lot of experience to really understand edge analysis via tactile feedback.  For example, a toothy edge is going to feel very different than a highly polished edge even when both are very sharp because the toothy edge is going to grab at skin and will have more sliding resistance, while a polished edge will ride on the surface of skin until it cuts.  You can easily demonstrate this on tomato, broccoli, onion or grapefruit skin.
 
In answer to your question, “What’s up?”, it’s difficult to say exactly.  Just guessing; it’s probably a combination of things like a toothy/polished edge, edge bevel angle, is there any burr on the edge, how tough are your finger tips, etc.  That kind of thing.
 
For crude, subjective quick tests, I’d stick with the well known methods of cutting paper, hang on a thumbnail or plastic pen, that kind of stuff, but when you really want to know, trust your BESS numbers. 
 
Obviously you are doing a great job of sharpening or you would not be seeing 160 – 230 numbers!

I'm curious, what do you think that it might mean?  Have you had good luck with the three finger test?  If you do the three finger test and conclude that a blade is sharp, can you relate that to a BESS number?

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Hi, Grepper,  Yes, my knives are sharp.  They cut paper and grip on a fingernail or pen.  I don't shave hair, because I have an aversion to skin bacteria.  Giving or receiving!  My belt progression is:  120 grit Trizact Gator; extra-fine Scotch Brite; and then a linen belt with 4 micron cbn.  Maybe the Scotch Brite belt takes away the toothiness.  I used to use a leather belt, but they stretch too much and took a long time to remove the burr.   

My set-up at the Farmers Market includes 3 Viel sanders, so I don't have to change belts.  I tend to get busy, and changing belts slows me down.  
  
The Scotch-Brite belts sure remove the burr!  Maybe the 3-finger test is bogus, I don't know.  But I can put lots of pressure on the edge with my fingers, slide them along the edge, and not cut myself..  I just want my customers to be happy.     .....................Dan                 Thanks for replying, Grepper.  I really appreciate it.