Thread: Establishing a Bevel

Originally Posted by PapaBull

No, I never tape the spine. That throws off the geometry of the razor, in my opinion. All areas that contact a hone end up being highly polished by the time they're shave-ready and the spine is no exception. I know some worry about excessive hone wear on the spine, but the spine is designed to wear down evenly, maintaining the geometry and once a razor is honed and the blade restored, it may never see a low-grit hone again.

I had a recent e-mail correspondence with John Crowley on this recently. A while back I gave the formula for calculating the bevel angle of a razor. A typical angle is about 11 degrees, on a 5/8 with a 1/8" spine. If you tape the spine and take down the edge by 1/16" then hone the usual way to restore the angle as closely as possible, the angle may increas to 12 degrees.

I like to tape when I use coarse grits because the metal comes off really fast, and it's not easy to control. If I don't take it off the spine, the taped spine will act as a guide for the edge (assuming I take it down that way) and I don't have to worry too much about the edge not staying parrallel with the spine. When I remove the tape the unchanged spine will act as a guide and the edge comes back into alignment. It's not so easy if you've removed a lot of metal from the spine unevenly.

I use this big 220 stone to re-establish bevel after heavy restoration, but some might think it's too coarse.



available here:

http://www.epicedge.com/shopexd.asp?...68494419507306

Joe, I think where people get into trouble with uneven spine wear is when they try to hone out nicks and stuff by honing as usual except honing more on one part of the blade than another or applying more pressure there. When reshaping the blade due to previous poor maintenance and honing or chipped edges, sharpening out those nicks or upside-down "smiles" is a horrible waste of time and is a great way to get uneven hone wear on the spine.

If, on the other hand, the blade is shaped first by 90 degree honing (instead of 11 degree honing), the spine is as far away from the hone as it can possibly be and you have the opportunity to shape the blade as best suits your needs. Once that's done, I think it's important to put the razor on the hone as it was meant to be and then restore the bevel to the new edge geometry. A blade's spine is designed to wear along with the blade and if one wears without the other, the result is a greater deviation from the intended geometry every time it's honed as such.

But it's a pretty personal thing and I know some people prize the pristine look of an untouched spine. But a razor with a 6/8" blade shouldn't have a spine that was intended for an 8/8" razor and with enough honing, that's what we end up with if the spine is "protected" from the hone.

Originally Posted by PapaBull

If, on the other hand, the blade is shaped first by 90 degree honing (instead of 11 degree honing), the spine is as far away from the hone as it can possibly be and you have the opportunity to shape the blade as best suits your needs. Once that's done, I think it's important to put the razor on the hone as it was meant to be and then restore the bevel to the new edge geometry. A blade's spine is designed to wear along with the blade and if one wears without the other, the result is a greater deviation from the intended geometry every time it's honed as such.

If you do it this way you'll end up with jus about the same angle as my way with a little more spine wear. I protect the spine getting down to the slightly larger angle the tape produces, then I go to essentially the same angle as you. The difference is if I was a little out of parallel after the 90 degree honing, the taped honinng will restore it.

The spine is the only thing that holds the razor rigid. I'm thinking that spine wear and not edge wear will determine when the razor becomes useless.

I'm also trying to think of this another way. If you always hone the spine and edge at the same time (you don't do that either) you will be taking the same amount of material off of each. In order to keep the same angle you would need to take off the spine onl 20% of what you take off the blade width. So, you are changing the angle. What's more, if you took 1/16" off the edge and started with a 1/8" spine, it would be down to almost nothing. So, if you're taking a lot of material, like with a chip you have to do it with out taking down the spine or you'll have no spine.

I would usually start with the 1000. A minute or two of light circles on either side should do it without too much wear on the spine. Proceed then to some cirles on the 400 followed by an aggressive pyramid up to 25 on the 4k. That should do it. Doing the work without a 4k, I would do many more circles and tape the spine.

X

Originally Posted by xman

I would usually start with the 1000. A minute or two of light circles on either side should do it without too much wear on the spine. Proceed then to some cirles on the 400 followed by an aggressive pyramid up to 25 on the 4k. That should do it. Doing the work without a 4k, I would do many more circles and tape the spine.

I know you understand this, but I want to make it clear for the readers. I would only use tape if had a chip or needed to remove a lot of material. That's also the only time I would use the 1K. Otherwise thw 4K should be good enough.

I tape the spine while I remove the nicks and restore the bevel. Then I remove the tape, but not before.

Originally Posted by jmsbcknr

Thanks for the help. I have a norton 1000 and have been using it on the real dull razors to attempt to get a clean bevel from the tip to the back. I have been taping the spine, but will stop that in the future. The theory of keeping the entire razor in contact with the stone.

jmsbcknr

I used to use coarse grits to remove the nicks and restore the bevels. But... I noticed that when I would reach the 8000 the razor would occasionally develop microchips.

When I stopped using grits coarser than 4000 that problem almost disappeared. My speculation is that the coarser grits
created "fractures" in the steel.

Next, I doubt that the angle on a razor is really that sacred.
I have met men who use razors so badly worn that is amazing.
But they still use them every day! And frankly, most of us have so many razors that we will probably never see any appreciable wear on our razors. I tape my razors because I don't like to see the wear pattern on the shoulder.

OK, time for bed,

One can shave with a very poorly maintained razor. No doubt about it. I've had pocket knives I kept sharp enough to shave with. I never did shave with them, though, since I much prefer a really comfortable shave. The original bevel was put in place for a reason and not arbitrarily assigned. If a manufacturer thought 12 degrees or 13 degrees was just as good as 11 degrees, I imagine that's what they'd have built into their razors since the more obtuse bevels are more durable. But..... the nice thing about razors is that you can maintain them however you want and if you're happy with the shave; that's all that matters. It's good to have more than one perspective.

I've never met Randy, but I probably fall into the category he mentions. My two razors are almost assuredly badly worn/honed, but I shave with them anyway. When I shave, I never have the razor flat against my face. I have the spine tilted up to where it just feels right when I shave. So, in practice I would say that small angular differences do not make much difference.

p.s. now that I've discovered SRP with all this valueable knowledge, I plan to correct the badly worn/honed aspects.

Mike