Thread: How Bevel is Affected by Taping

Originally Posted by English

My point on taping is that you can also use tape to hide the fact that you have been honing or over honing a razor.

I don't understand this statement. If the razor is sharp enough to shave then it is impossible to hide the fact that it has been honed. What indicates the razor has been "over honed" if not excessive removal of spine material and/or edge? If taping prevents excessive spine wear doesn't taping then prevent "over honing"?

Originally Posted by English

I think that it proves a point.

To be honest IMHO if a blade needs to be taped to be honed, sell the razor on E Bay, because it's got a basic design flaw

I still say this even if the razor has pretty etchings or gold or diamonds or whatever.

Razors are for shaving and a nothing else. They are an instrument and shouldn't require special treatment.

I've said it before and Ill say it again, a new razor that needs to be taped to be honed is badly designed.

Originally Posted by English

My point is if you can not see the true hone ware you can not tell the usage including over honing by previous users. This includes learners and the inexperienced.

As I have said before taping a spine is hiding the truth. I don't say it's done with intentional bad intentions but the fact is the hone ware on a taped spine means the spine and blade ware don't match.

That for me is cheating and the razor becomes untrue.

Last time I said this some members went up the wall trying to justify why I was wrong in my view.

Inexperienced honers, taping spines while they learn how to hone is not the way forward.

The general message I would put out is that taping a spine by an inexperienced honer is likely to corrupt the original geometry of the razor to such an extent that it will probably impact the quality of the shave.

But of course if you buy a razor, you can do what you like with it.

You should tell Mr. Zowada that ALL of the razors that he has produced thus far have been “flawed” because of the tape he uses on the spine to protect the Damascus finish and that he can send them all to you for proper and immediate disposal.

Brad,

How you measured A has me baffled! If you measured directly between the point where the bevel meets the flat surface and the edge of the blade, then you didn't measure A, you measured the hypotenuse as Jimbo noted. (although the angle is so small, the results should be very close either way - where's my calculator?) If you indeed measured A, then where on the razor did you actually place the plastic scale? I may be wrong (to borrow a qualifier from Jimbo) but I don't think there is anywhere on the razor you can place a plastic scale to get an accurate reading for A. Is A really as it appears in the diagram, or are the vertical lines denoting A not supposed to be directly vertical?

Thank you for your upcoming correction!

A as hypotenuse ...... A as adjacent

Actually, I think the main reason Tim uses the tape is because all of his razors have a double bevel and not only a double bevel but a very very fine double bevel. The only problem with the double bevel (to me) is that 1-I find no difference from a practical shaving point of view between a single or double bevel and 2-to properly care for the double bevel you need to know the thickness in mils of the tape the grinder used. If he uses 2 pieces of 4 mil tape and you use 2 pieces of 6 mil tape you might wind up with an altered bevel. Possibly you could wind up with three bevels or remove the double altogether depending on whether you are on the thin or thick side.personally to me its not worth the added hassle each time I have to do a touch up. I realize some guys love double bevels. I hate them with a passion.

Oh and to the original idea of the post you have to realize there are probably more people who buy razors as strictly collectibles that who actually shave with them. Also there have always been highly ornate razors crafted so taping a spine is the best way to protect an ornate finish on the spine.

Originally Posted by icedog

Jimbo,

You are right, you are wrong.

In my measurements I reduced the razor blade down to a right triangle. The diagram I so poorly drew is essentially the same as the way awesome diagram Seraphim somehow posted (except my edge is pointing toward the right and I called my adjacent side A and my opposite side O). The hypotenusala is actually an imaginary line drawn somewhat through the razor from the center of the thickest part of the spine to the edge.

Sorry, but he's right. you can't just flip the triangle around because your measurements and the equation are dependent on the right angle being in the center of the blade between the honing flats.

The formula for angle, as corrected, is 2 * asin( (T/2) / S), where T is the thickness between the honing flats, and S is the distance from the edge to the part of the honing flat that was used when measuring T.

As for the tape, I've never found the difference in angle to cause a problem when honing. Just leave it on the entire time. The difference in angles also won't cause problems with stropping, unless you've got a huge bevel.

As for the relative rates of spine and blade wear, I think you'll find that the edge always wears faster than the bevel. If it doesn't, then the hone will never touch the edge of the blade - you'll always be in the sort of situation as when you first untape the spine.

Originally Posted by mparker762

Sorry, but he's right. you can't just flip the triangle around because your measurements and the equation are dependent on the right angle being in the center of the blade between the honing flats.

The formula for angle, as corrected, is 2 * asin( (T/2) / S), where T is the thickness between the honing flats, and S is the distance from the edge to the part of the honing flat that was used when measuring T.

As for the tape, I've never found the difference in angle to cause a problem when honing. Just leave it on the entire time. The difference in angles also won't cause problems with stropping, unless you've got a huge bevel.

As for the relative rates of spine and blade wear, I think you'll find that the edge always wears faster than the bevel. If it doesn't, then the hone will never touch the edge of the blade - you'll always be in the sort of situation as when you first untape the spine.

Icedog is right based on his diagram. Don't be fooled by the placement of the vertical lines surrounding the A, be concerned only with their vertical alignment, pointing toward the imaginary adjacent middle line. Perhaps icedog actually measured the hypotenuse though, rather than A?

I'm certainly not into this as much as some of you guys, but if razors are such crude utilitarian tools, I can't imagine the thickness of a piece of electrical tape is going to make that much of a difference.


Jordan

Originally Posted by jnich67

I'm certainly not into this as much as some of you guys, but if razors are such crude utilitarian tools, I can't imagine the thickness of a piece of electrical tape is going to make that much of a difference.


Jordan

How much is Tim charging these days for his crude tools?

Originally Posted by hoglahoo

Icedog is right based on his diagram. Don't be fooled by the placement of the vertical lines surrounding the A, be concerned only with their vertical alignment, pointing toward the imaginary adjacent middle line. Perhaps icedog actually measured the hypotenuse though, rather than A?

Yes, that's what he's doing based on his textual description (it's also pretty impossible to measure from the edge to the bisection of the line between the honing flats, because there's steel in the way). But if you measure along the honing line from the edge to the honing flat then you've got to use the arcsin function to get the angle, which is the point Jimbo and I have been trying to make.

Originally Posted by hoglahoo

Brad,

How you measured A has me baffled! If you measured directly between the point where the bevel meets the flat surface and the edge of the blade, then you didn't measure A, you measured the hypotenuse as Jimbo noted. (although the angle is so small, the results should be very close either way - where's my calculator?) If you indeed measured A, then where on the razor did you actually place the plastic scale? I may be wrong (to borrow a qualifier from Jimbo) but I don't think there is anywhere on the razor you can place a plastic scale to get an accurate reading for A. Is A really as it appears in the diagram, or are the vertical lines denoting A not supposed to be directly vertical?

Thank you for your upcoming correction!

A as hypotenuse ...... A as adjacent

Lee,

Wow what a great diagram you made. I guess this is done with some CAD program? I am so ignorant I can barely function in this world. You and the other folks of this community are teaching me alot about alot.

Anyway, what I did is closer to your diagram to the right, "A as adjacent". I say closer becauase it is a crude measurement used only as a reference point in a calculation. I layed a plastic drafting scale on the side of the blade and measured (to the nearest sixteenth) from the edge to the thickest point (what contacts the hone surface). I then measured the thickest point of the spine with a digital caliper and divided that by two so that the blade is essentially split longitudinally into two equal triangles. I did not do this to get the actual angle of the razor's edge. Does anyone really care what that is? One has only to look at a full hollow to know it is a pretty shallow angle. I did this exercise to quantify the difference an additional .007" added to the spine of a razor being honed would make. While you guys may argue the measurement is actually hypotenuse as opposed to adjacent, I think you'll find that with such a shallow triangle, that point is moot. Now I may be wrong but I believe, in this case, what is important is the delta.

Am I wrong?

Brad