Deba profile

[knife-kait]

Hello.

I was gifted an family deba. It need some work. I'm uncertain how to maintain the profile of it. Is it a single bevel and grind or should there be a compound ground to the edge (either two angles or several angles forming a curve)?

Also I have seen debas where there is a concavity to strengthen the edge (slight but a concavity). This is on the 'flat' - back part of the blade. This knife appears to have lost/never had that. How do I get that back or should I just ignore that detail?

 

[jc57]

Usually debas have a wide bevel that is either flat or convex, on the side that corresponds to the handed-ness of the knife. I.e., if it's a right-handed deba, the bevel is on the right if you are holding it by the handle. Sometimes there is a small microbevel applied to the edge on that side.

The opposite side is either pure flat, or has a slight concavity to aid in food release, with the outer edges usually ground flat (the concavity doesn't go all the way to the edge).

You maintain the knife by sharpening the entire wide blade road (main bevel) all the way to the edge, on the side that has the bevel. Microbevel is up to you. And then deburr on the flat side.

Korin has a quickie diagram on their web site here: http://www.korin.com/site/PDFs/knifesharpeningbasics.pdf

Jon Broida from Japanese Knife Imports has done a number of videos about how to maintain single-bevel knives: Here is link to his YouTube channel:

https://www.youtube.com/user/JKnifeImports/search?query=single+bevel

Usually the concavity on the back is put there at the factory when the knife is made. They don't ALL have that. Depends on the maker. They are put on with really big (wide radius) round grinding stones which make for a slight concavity (due to the side of the stone). I've seen pictures of the stones on some web sites. You could probably replicate that with a belt grinder and some sort of slightly convex platen if you wanted to. Way beyond my realm of knowledge. I'd leave it flat if it came that way.