Thread: wider bevel=more flex?

That pic was taken using very light pressure of the blade against the edge of my desk. It flexed back immediately from the distortion seen there.



I subsequently re-ground that Wapi, and you can see here, that as a result, the bevels got much wider, and I can tell you that there was no flex remaining as there was in the original blade.

Originally Posted by Seraphim

I subsequently re-ground that Wapi, and you can see here, that as a result, the bevels got much wider, and I can tell you that there was no flex remaining as there was in the original blade.

Interesting....that must be because the new bevel is now in the thicker part of the blade, since it's closer to the spine....

Originally Posted by Seraphim

That pic was taken using very light pressure of the blade against the edge of my desk. It flexed back immediately from the distortion seen there.



I subsequently re-ground that Wapi, and you can see here, that as a result, the bevels got much wider, and I can tell you that there was no flex remaining as there was in the original blade.

I'm very puzzled, are you saying that the Wapienica flexes less after you have ground it thinner?

Originally Posted by Bart

I'm very puzzled, are you saying that the Wapienica flexes less after you have ground it thinner?

Yes, as the thin, unsuppported edge part was removed, and thus the bevel is now formed on the thicker portion of the grind:

Bart, I think he took some off of the blade as Dave said and got into a thicker part above the original edge.

Dave, just for kicks I would take that blade and breadknife it down aways. Then I would use one piece of tape to make up for the spine wear. get a decent bevel on it and then add two more as Tim Zowada does and create a double bevel. Might be stronger and hold an edge better ? Interesting experiment anyway if you're into trying that sort of thing.

Originally Posted by Seraphim

Yes, as the thin, unsuppported edge part was removed, and thus the bevel is now formed on the thicker portion of the grind:

Ah, you ground it smaller, instead of thinner...
What a great relief. I almost thought someone had been tampering with the laws of physics...
Thanks for the clarification Seraphim (and Jimi)

Bart.

Originally Posted by Bart

2. the thickness of the blade.
A full hollow has a very thin blade, hence a small bevel is to be expected. A wedge has a thick blade, hence it will carry wider bevel sides. In this case the wider bevel will be a bit sturdier, because it contains more steel for the same height. (it has a wider base).

Not sure if you said that quite right? Assuming that "wider bevel" means that the bevel is "taller" extending further toward the spine from the edge then, at the same height (distance from the edge towards the spine) it would only contain more steel if the bevel angle is wider. The implication being that wedges have thicker spines for the same width blade.

Originally Posted by Quick

Not sure if you said that quite right? Assuming that "wider bevel" means that the bevel is "taller" extending further toward the spine from the edge then, at the same height (distance from the edge towards the spine) it would only contain more steel if the bevel angle is wider. The implication being that wedges have thicker spines for the same width blade.

Let's try a quick drawing.
On a theoretical full wedge, the bevel is equal to the razor. If we start to take away steel, by hollowing the sides of the wedge, we also take away steel from our bevel sides. They simply can't extend that far anymore because there is no steel to occupy. The hollower, the lesser steel left to be part of the cutting bevel.
One way to look at is is to realize that on a hollow razor, a part of the cutting bevel can't exist, because it was already ground away by the maker of the razor. In a way of thought, part of the steel has been removed for us during the production so we don't need to remove it during sharpening. (that is one of the historical reasons for hollowing a blade)

Originally Posted by JimmyHAD

Dave, just for kicks I would take that blade and breadknife it down aways. Then I would use one piece of tape to make up for the spine wear. get a decent bevel on it and then add two more as Tim Zowada does and create a double bevel. Might be stronger and hold an edge better ? Interesting experiment anyway if you're into trying that sort of thing.

That would actually make for a good experiment! I would have to get my nerve up first though...something about breadknifing an already shave-ready edge just doesn't sit right in the gut!

Wow! I wasn't aware of that. You mean that the blade is actually thinner at the full hollow point than at the edge?