Differential sharpening

[fishbulb]

I have seen various posts where people suggest sharpening different portions of their blade to various grits to get various performance characteristics out of the same knife; for example a polished point with a rougher belly portion. Has anybody ever tried sharpening the same blade to different bevels to get a similar result?

I would think putting a more extreme bevel on the front portion of a blade for slicing and a less steep grind on the rear portion for increased durability would be a great compromise. If you really wnated to go all out this could be combined with the various grit method.

 

[JohnW]

Tailoring sharpening to its exact use is probably the best way to go. It's only when you need to handle a broad range of tasks equally well, that you start making general compromises.

 

[Cliff Stamp]

Most high end knives are ground in this manner, often it is not the edge angle that is varied, but the edge thickness. One light hunters for example they are much thicker near the choil than out by the tip. Exactly as you note then you have a strong base to work with near the base, and a much higher performance tip for delicate cutting. A distal taper does the same thing on a larger scale.

-Cliff

 

[Jeff Clark]

I try like crazy to avoid variations in my knife edges. I consider it dangerous. The commonest way to have an accident with a blade is edge variation. You start a cut on a comparitively low performance section of a blade (typically just dull from wear) and you apply a high level of force to get a cut started. As your cut progresses your slicing advances to a thinner/sharper section of the blade and zooms through it out of control. Whenever I get a knife that is thicker near the choil I reprofile it to make the blade even.