Thread: Theory

So I have been reading up on knife sharpening. Knife sharpeners are pretty obsessed about making sure they have bevels that are symmetrical. The theory seems to be that on a double beveled knife, if the angles on the bevel isn't even on the one side compared to the other, you have compromised the edge.

OK so if you buy into that (if not please debate), with respect to our concerns here, the straight: I wonder if uneaven spine ware on one side of a straight as compared to the other, would make a big difference owith respect to shave comfort??

With the angles we go at it, would a degree or two difference on the bevel from the one side compared to the other make a desernable difference you figure??

Just thinking out loud as it were... Any thoughts?

Wait, my Kami doesn't have an "even bevel.". It shaves great! Its a completely different shave though.

Yeah... I don't know??

I dunno, an edge is an edge and if the bevels meet what difference can it make?

Bob

In the knife world, and perhaps kitchen knives in particular, you'd get steering if you didn't make sure the edge met what was to be cut with a symmetrical cutting edge.

Now, the Japanese cutlery (I'm talking double bevelled knives here) in particular is designed to be e.g. 80/20.
They do have minute differences in their whole grind on each side though, to make up for that.
That is by design, it helps in food release amongst other things.
So a knife like that is made for left hand or right hand use only.
Well, often anyway.

So no, symmetrical isn't always desired in a cutting tool.

Kamisori's and single bevel knives is a whole other thing as well

Originally Posted by BobH

I dunno, an edge is an edge and if the bevels meet what difference can it make?

Bob

I really don't know Bob. You might be right!! As a rule I hang out here - but when no one could help when I was looking for advice on sharpening my kitchen knives with Arks, I started to scour the knife forums and noted this obsession on angle!!

wouldn't an uneven bevel make it necessary to change the blade angle while shaving to make it shave the same on both sides of the face?

Originally Posted by Birnando

In the knife world, and perhaps kitchen knives in particular, you'd get steering if you didn't make sure the edge met what was to be cut with a symmetrical cutting edge.

Now, the Japanese cutlery (I'm talking double bevelled knives here) in particular is designed to be e.g. 80/20.
They do have minute differences in their whole grind on each side though, to make up for that.
That is by design, it helps in food release amongst other things.
So a knife like that is made for left hand or right hand use only.
Well, often anyway.

So no, symmetrical isn't always desired in a cutting tool.

Kamisori's and single bevel knives is a whole other thing as well

I have one of those 80/20 blades!! Its awesome lol!!

Anyway - what do you think Bjoernar with respect to most European straights - they are designed to be symmetrical, if you compromise the angle, do you think you would compromise the shave??

Originally Posted by earcutter

I have one of those 80/20 blades!! Its awesome lol!!

Anyway - what do you think Bjoernar with respect to most European straights - they are designed to be symmetrical, if you compromise the angle, do you think you would compromise the shave??

I don't see how a slightly asymmetrical bevel would affect a shave to be honest.
On a hollowed blade, as long as there is a bevel on each side and the apex of the edge is polished on bloth sides I'd suspect it would be hard to notice.

On larger wedges, one could perhaps hone it so much more on one side that it would affect the angles used for shaving with each side of the blade against the face.
But I'd say that even then it would be veery small differenses, and that a shave would be easily had with such a blade too.

I mean, many here shaves using kamisori's on both the Ura and Omote side against the face.
They seem to do alright

Originally Posted by Birnando

I don't see how a slightly asymmetrical bevel would affect a shave to be honest.
On a hollowed blade, as long as there is a bevel on each side and the apex of the edge is polished on bloth sides I'd suspect it would be hard to notice.

On larger wedges, one could perhaps hone it so much more on one side that it would affect the angles used for shaving with each side of the blade against the face.
But I'd say that even then it would be veery small differenses, and that a shave would be easily had with such a blade too.

I mean, many here shaves using kamisori's on both the Ura and Omote side against the face.
They seem to do alright

I know I do!! Don't tell anyone !!

Thanks for the input!!

Originally Posted by earcutter

I really don't know Bob. You might be right!! As a rule I hang out here - but when no one could help when I was looking for advice on sharpening my kitchen knives with Arks, I started to scour the knife forums and noted this obsession on angle!!

Here's my go on cutlery: choose angle and finish of bevel for purpose/durability. THEN set a full bevel. I've learned that the easiest, and fastest way to do this is to hone until you start pushing a burr. Then progress up the grits, polishing bevel and honing burr away.

A knife can feel really sharp without making the bevels meet. I learned this before i started honing razors. The burr-method came from studying Japanese knife videos.

My deda has taken over nearly all regular kitchen chores, just too easy to keep fully sharp free-handing it on a King. Camillia keeps the stains away. I still use jiggeries on double bevel stuff.

Even, mirrored bevels are quite pretty, but functionality requires neither.