Thread: Scratches on the bevel

I wanna understand why some people worries a lot about scratches on the bevel of the blade?
Does it matter?
what we need to have edge not the bevel?
if anyone can explain why we need shiny bevel i would appreciate.

Functionally it does not matter as long as the edge is sharp. I am one on my wedges that have big bevels I like them to look their best. I don't want them looking raw and unfinished.

Mike

I personally do not use optics as my primary means
of assessing an edge, so I will only feel sharpness --
if there are still scratches I'm oblivious!

- Scott

I have to agree that if the edge feels sharp and shaves well, then why worry about scratches on the bevel? On the other hand though, it seems to me if the bevel is crisp and shiny then that smoothness should logically follow itelf all the way to the edge, producing a much smoother finish, and a much smoother shave. If the bevel shows scratches, are you suggesting they stop just before they reach the edge, and the edge is smooth anyway? Just asking.


Ray

Originally Posted by rayman

I have to agree that if the edge feels sharp and shaves well, then why worry about scratches on the bevel? On the other hand though, it seems to me if the bevel is crisp and shiny then that smoothness should logically follow itelf all the way to the edge,

sorry to say smoothness or sharpness has nothing to do how your bevel look like

producing a much smoother finish, and a much smoother shave. If the bevel shows scratches, are you suggesting they stop just before they reach the edge,

No they don''t but edge cold be smooth anyway depends on the grit of the stone

and the edge is smooth anyway? Just asking.

i fully understand and asking is ok this is how we learn

Ray

It is ok to ask and learn i always do it myself

Originally Posted by hi_bud_gl

It is ok to ask and learn i always do it myself

I must admit those are some interesting concepts you are proposing. My understanding of this honing process has always been a little different than that though.

It has been my assumption that we generally start honing at the 1k level to produce a bevel for the base, then go to the following: 4k, 8k, 12k, 16k, finishing stone, .5 paste, maybe .25 past = 60k, then linen, and finally strop. Each step leaves a different looking bevel and edge. All the way to the linnen, the bevel shows a finer and finer scratch pattern. It has been my belief that these scratches are a result of, and not a byproduct of the work done by the stones. At this point the smoothness of the edge should look much finer under a scope. When we go the linen and then the strop I always thought the purpose of that was to smooth out the final peaks in those scratches to produce the finest edge possible, thus if the bevel looks polished, as opposed to scratchy, and without the use of a loop or scope, I would expect that edge to be smoother as well since the smoothness should continue out to it.

I still have to give some more thought to your position though.

Ray

The "Scratches" on the bevel are technically referred to by toolmark examiners, those who study and compare the scratches, as "Stria" striated toolmarks or sliding stria toolmarks

Fine marks on a surface left by a tool, when a tool slides over a surface or creates a new surface by cutting through a material.

A good model is a serrated knife slicing butter, or marks on a bullet, the impressions of the lands and grooves from rifling and the finer stria on the land and groove from the steel that in turn is left by the edge of the button cutting the original land and groove by the factory or gunsmith or the razor edge sliding upon the stone, polishing grit or even paper.

I believe the confusion may come from the age old tradition of polishing the back side of a chisel or smoothing plane blade to a mirror finish, which is in fact creating smaller or microscopic stria.

On a chisel or plane blade the back side’s finish or the size of the stria is critical to the ultimate sharpness of the chisel as only one side of the bevel is ground.

Where the two planes meet, the back of the chisel/plane blade and the bevel determine the sharpness of the point. The edge looked at under magnification looks like a saw, with the stria edge as the gullets. The smaller the stria, and there is always stria though possibly microscopic the smaller the gullets and sharper the point, the cutting edge.

So polishing is absolutely critical for a sharp chisel/plane blade edge.

But with a razor or knife you areproducing a bevel on both sides and creating new stria on both bevels with each pass on the tool, the sharpening medium.

The size of pre-existing stria on the bevel is of no consequence as it is abraded and a progression of finer stria is produced in the sharpening progression. The edge is also abraded reducing the width of the blade, the surface of the bevels and the pre existing stria.

The goal as I see it is to produce the finest stria on both sides of the edge for the finest, sharpest edge. This is one of the outcomes of a Micro Bevel when we polish or re-grind only the edge by increasing the bevel angle.

The question is how sharp is sharp enough? That is where the other factors come into play, quality of the steel, angle of the bevel, quality and consistency of grit size and ultimately the medium to be cut, the facial hair.

And possibly most important the expertise of the operators, the honer and end user, their ability to achieve consistency… and that is where experience comes into play

Originally Posted by M Martinez

...Where the two planes meet, the back of the chisel/plane blade and the bevel determine the sharpness of the point. The edge looked at under magnification looks like a saw, with the stria edge as the gullets. The smaller the stria, and there is always stria though possibly microscopic the smaller the gullets and sharper the point, the cutting edge.

So polishing is absolutely critical for a sharp chisel/plane blade edge.

But with a razor or knife you areproducing [sic] a bevel on both sides and creating new stria on both bevels with each pass on the tool, the sharpening medium.

The size of pre-existing stria on the bevel is of no consequence as it is abraded and a progression of finer stria is produced in the sharpening progression. The edge is also abraded reducing the width of the blade, the surface of the bevels and the pre existing stria.

The goal as I see it is to produce the finest stria on both sides of the edge for the finest, sharpest edge. This is one of the outcomes of a Micro Bevel when we polish or re-grind only the edge by increasing the bevel angle...

First off, I am not being contradictory for it's own sake here, but it seems these (in red) statements are in opposition to each other:

Whether or not you are working on one side of the bevel or both sides together, your statements above indicate that smaller striations=better cutting edge.

How can that not apply to a razor's edge?

I am begining to think that there are two schools of thought to look at bevels, literally.
School I : The Classic Bevel. This the type of bevel that Lynn and other well known pros have been doing for years and even generations. It is a world class standard and arguably produces the best shave possible within the design limits of the materials. They seem to think that shinning bevels and getting rid of scratches is functionally a waste of time and the scratches themselves are in their own way contributing to the superiority of the proven standard. Honemeisters, correct that statement if it is wrong.
School II. The Experimenters: This is not a more advanced school because if you do not have excellent honing skills it is more than likely going to waste your time and money. The goal is a smoother edge produced by better sorted nano particle hones or natural ones going to produce a strong serviceable edge? How will it compare with the classic edge? To be continued...
Mike

Originally Posted by Kingfish

I am begining to think that there are two schools of thought to look at bevels, literally.
School I : The Classic Bevel. This the type of bevel that Lynn and other well known pros have been doing for years and even generations. It is a world class standard and arguably produces the best shave possible within the design limits of the materials. They seem to think that shinning bevels and getting rid of scratches is functionally a waste of time and the scratches themselves are in their own way contributing to the superiority of the proven standard. Honemeisters, correct that statement if it is wrong.
School II. The Experimenters: This is not a more advanced school because if you do not have excellent honing skills it is more than likely going to waste your time and money. The goal is a smoother edge produced by better sorted nano particle hones or natural ones going to produce a strong serviceable edge? How will it compare with the classic edge? To be continued...
Mike

I'm not going to disagree exactly, but I will add: whoa take it easy tossing the bests, and superioritys around will ya Mike?

An easy way to look at it is like this: Can you shave well enough from 4k? (why yes, I can) can you do it from 8K(indeed).... so a combination of those two are likely to work as well. Equally so if the edge is composed remnants of 8, 12, 16 etc.