I have been watching with interest some videos on You Tube by virtuovice. He regularly thins his hunting knives to improve the cutting abilities.
Inspired by him I bought a cheap Boker hunting knife (original bevels were 25˚so a total of 50˚only good as an axe) it is a heavy little knife 5mm on the spine 440 stainless since I do not have the WE as yet I did it on waterstones 150-1000-5000 then DMT extra extra fine . The right hand side of the blade I tapered from about 2mm down from the spine to the edge once I was through to the edge I then put a convex bevel going from about 3˚ at the point to about 5˚by the handle . The left side I convex tapered from about 8mm in from the edge to the edge then I put a convex bevel of about 12˚ at the point graduating back to the handle to about 15˚. The result it shaves, slips through paper & feather sticks beautifully the blade probable would not take beating against logs but it is very sharp in its original state it would barely cut anything .
It seems to me that the more I sharpen whether it be currently with an EP and shortly with a WE or Japanese bench stones or diamonds that the most important thing is the taper to the edge whether this be chefs knives or any other sort of knife .
We can all make a sharp bevel but if the metal behind it is too wide it is pretty immaterial how sharp the edge is this is particularly so with kitchen knives.
I was given a Santoku wannabe knife the other day it was thick heavy and blunt perhaps they made it heavy to make up for the poor edge I had to re-profile the lower third of the blade to the edge should have binned it really but I decided that since this cook had bought it herself I had better sort it since the other knives were not so bad.Apart from the thinning it been a cheap knife the steel was not laminated so it was quite tough the end result was a knife that was very sharp and did what it had never done since the knife had not been sharpened when it was given to me. I think I would be wary about doing that to a cheap knife for someone without charging a price possible more than it would cost to buy probable a job for Tuffy's Kally . Still not practical for me at the moment since I live in an apartment & if I am sharpening at home it is in the kitchen I don't think a belt sander in a kitchen is very wholesome.
Below are some images of the Boker. The first image is upside down so the left side in the picture is actually the right side!
Very good points, Leo. A way to really improve cutting performance of your knives is thinning them behind the edge. I've done this on nearly all of my kitchen knives.
I'm really looking forward to the low angle attachment. My favourite chef knife is thinned out at an angle of about 11 degrees, after which I put a 15 degree edge on it. I would be great if I could achieve this with the low angle attachment.