Knife edge question

[dragon rider]

I've heard that a single bevel knife edge, for example the type that Japanese chefs use, can be made and kept sharper than a double bevel edge.  Dr. Ashby's broadhead research seems to confirm the theory, yet nearly all knives at least in the US are double bevel.  So, my question is, what am I missing?  Is the theory wrong or are there are other limitations to the single bevel?  Thanks.

[Steve Nuckels]

Humm!  Interesting thought!  I will be watching!

Steve
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IN GOD WE TRUST

[LAR43]

A lot knives used for slicing only are single edge because of their ability to be made razor sharp, but they don't handle abuse/hard use as well as other bevel styles.

Double bevels, & there are a few different kinds, can be used harder & will hold their edge longer depending on the shape, are most common on multi puropse knives like we use.  

Larry

[dragon rider]

That makes sense.  Thanks.  Most of the single bevel knives I was able to find on line while doing my research were sushi knives, which requires precise work, but not really hard use.  I'd be willing to bet that the best of those are probably custom ground for the individual chef so there's no left hand/right hand issue.

Thanks again.

[Lamey]

IF the edge/blade is truly "flat" on 1 side it will feel different when cutting.  Sometimes I forge them flat on 1 side with a bevel on the other.  Then when Im grinding in I will put a convex on the "flat" side.  This allows for a traditional feel when cutting, doesnt give that "planing" affect that you sometimes get the single bevel type of grind/edge.   Ive done alot of bigger Camp knives in this way,  and found when you do the convex from both sides, even though its a "single bevel" forge/grind,  the knife performs better  under heavy use especially.

If you are strictly talking about kitchen knives and slicing,  its a different matter.   Ive made a few like this and kinda like them,  as the flast side gives my knuckles a nice place to rest against when using on a cutting board.  

Alot of it has to do with how high the bevel is cut on the bevel side, the relationship between the spine/edge thickness and bevel grind.  

Generally when I convex the edge in on both sides, its also ALOT easier to sharpen, especially for those that are used to "centered" tradtional edges.

Do I think in a knife there is any advantage at all.... No.

[Lin Rhea]

One other thing that has not been mentioned is that the single bevel broadheads help the arrow to keep spinning even when in the animal. You generally would not want this on a knife blade, as Matt mentioned. Lin

[Bill Kissner]

A knife maker friend of mine told me this story. Every month he and several other makers get together for a day of testing and discussing different things. They always do the hanging rope cutting test. He said one month a knifemaker showed up with a single bevel blade and everyone was amazed how easy it cut the hanging rope. He said it beat every other knife hands down.

We have a few kitchen knives with the single bevel and I hate using them to slice anything because of them cutting at an angle making the slices uneven.

[Lamey]

Ive got about 100+ flat forged/single bevel blades out there, maybe more.   There is no real advantage in performance in any way that ive seen,  but they are fun to make and different.

On most of these the edge is actually more centered as i roll in the convex on both sides.  

Bill,  thats the effect I mentioned, the edge will tend to "plane", hence the "uneven" slicing.  When the edge is rolled in from both sides it really cuts down on that effect dramatically.