Thread: Taping the EDGE

Originally Posted by gssixgun

Again I have to somewhat agree with the English-man
But would state it a different way... An older used razor feels different than a Brand New / NOS Razor.... Ummmmmm Yeah we know

But most of us don't want to toss the razors that have 1/8 or more blade wear at this moment in time.... so we try to keep them shaving....

Not true with a wedge right? Maybe only with full hollows?

Hmmmmm I would think that it would not matter really, despite the blade contour as you move toward the spine, you are getting into thicker and thicker metal "the Belly of the Blade" so that would be changing the "feel"
But on the reverse side of that it seems that wedges / near wedges wear slower too

English has pretty much summed up my belief, the edge is different and stiffer once a significant part of the blade is honed away. 1/16" on a 5/8 blade is 10% while it will be different it will merely shave like a less hollow ground razor... for folks using the half and quarter hollows they will probably never notice the difference but those who use very hollow ground razors the blade flex and comfort is degraded.

yes honing without taping the spine will in time lead to wide flat spots of hone wear on the spine but the shave quality will only slowly degrade as far as i can tell.

my contention is that there is truly an optimum angle based on the type of grind and blade width.


Glen... the only taping thread i can remember was all about how much/ if taping effects the quality of the shaving edge as in how much it might change the angle at the apex.

Originally Posted by syslight

yes honing without taping the spine will in time lead to wide flat spots of hone wear on the spine but the shave quality will only slowly degrade as far as i can tell.

That's what I was ruminating about earlier. Even if the hone wear spots on the spine get wider (and flatter) the spine should still decrease in width at the same rate it did when the hone wear spots were thinner (and less flat).

Originally Posted by Quick

That's what I was ruminating about earlier. Even if the hone wear spots on the spine get wider (and flatter) the spine should still decrease in width at the same rate it did when the hone wear spots were thinner (and less flat).

If I were to come across a razor that had that had uneven wear on the spine I would probably pass on it unless it was a make or model I really wanted badly. In that case I would probably send it out for a regrind rather then trying to restore it myself. Edges are one thing but spines are for me a horse of a different color.

One more thing that comes to mind is my father telling me years ago that the further up you get into the blade of a pocket knife the temper changes. When you get a pocket knife that is honed to the point where the edge is now up into the belly of the blade the temper is not as hard as it was in the original edge.

I am not sure if this is correct but it made sense to me and if it is correct that means that the spine may be softer then the metal at the edge and wear at a faster rate if not taped. More knowledgeable members on the mysteries of temper and metallurgy will no doubt correct me if I am wrong.

There's really no way to generalize about how much of the edge can be honed away before the steel qualities begin to change (from regions of varying hardness).

But there is a key difference between straight razors and pocketknives that may be relevant; razors are intended to be honed laying flat, so the spine ought to be a similar hardness to the edge to minimize unpredictable hone wear, whereas pocketknives are only honed on the cutting edge, so the spine may be tempered to a lower hardness to facilitate a "tougher" blade by reducing the amount of brittle Martensite.

So for all intents and purposes a straight razor ought to have a uniform (or very close to uniform) range of hardness, a range that probably doesn't go out of the bounds of usability.

As for the test results of 9 to 18 degree bevel angle acceptability, that may or may not have been an experiment I did, but my results were more like ~12 to ~22 degrees. I made a series of razors that had bevel angles in that range and gave them all edges from the same progression of hones to see how the angle affected shave quality. I even took the ones with very acute angles and honed them with multiple layers of tape to identify the angle that was too large for the given piece of steel. The results were in the above stated range, with very little detectable difference if the angle was kept reasonably close to its original condition. The biggest difference was in the initial quality of the steel.

So while its good practice to keep a razors geometry as close to original as possible, the razor's performance isn't going to be adversely affected by an extra degree or two of bevel angle and may be perfectly fine with a few extra degrees more.

To each his own, I suppose.

Good point regarding the difference between pocket knives and razors. Thanks for the blade angle tests too.