Thread: Edge size

Ok.... Question..... I noticed when looking at some straight razor edges....some are fairly large and others are small. Some guys use tape and others don't. I know that over time the spine gets worn down and when people hone, the edges seem to get really "wide". I like the look of a smaller edge. Is there a difference between a larger or wider edge/ bevel and smaller one? I see this mainly on older vintage wedges. Back in the day were the edges really large from the factories?

This is something I have wondered about from viewing pics on ebay, others sites, and posts.
Maybe it is a matter preference too?

I find most of the wedges have larger bevel faces than my full hollows

There is a spine width to blade size ratio that gives the preferred bevel angle. The idea is that the spine will wear at the same rate as the bevel as you hone so the bevel angle should stay the same. That is the theory anyway. Old near wedges after decades of heavy handed honing may have the spine worn too thin to keep that ratio and the bevel width increases in size as a consequence.

To get back to the proper ratio layers of tape, within reason, can be added to the spine to get it back up to the proper width relative to the blade size. For honing a razor that is within the proper bevel angle range adding a layer of tape while honing is done to minimize hone wear to the spine. In that case the additional layer of tape makes very little difference to the bevel angle and any change can be ignored.

This should help explain it better http://www.coticule.be/wedges.html .

Bob

It is most definitely not a matter of preference.
A properly ground new razor should have a thin bevel. Fat bevels on a new razor are a sign of sloppy grinding. While it is true that the bevel gets wider over time, usually the really fat bevels are due to inexpert honing.

Now, the real issue is that the bevel is the part that sits on the stone, flat.
The wider the bevels are, the more metal you need to remove to hone a razor. With a razor that has really fat bevels, honing can take a loooong time, just because the surface is so large. In terms of honing and maintenance, fat bevels are not a preference but a functional defect.

The other reason why bevels get larger on wedge type blades is the amount of metal behind the edge. What I mean here is that two razors with the same geometry , one hollow ground and the other near wedge, should start off with the same bevel width. However, as the width of the blade decreases with honing, and the angle gets lower with spine wear, you start hitting a thicker part of the blade than you do with hollow ground.

Take a look at the profile of, say a Filarmonica extra hollow compared to a near wedge and it becomes obvious why bevel width will increase on the second much more than the first.

Like Rob said, many blades that have been honed a LOT are going to be thicker at the edge unless it has been reground no matter how much the spine has been worn down. If you have ground away 20% of blade, you are going to be in a thicker portion of the blade n most cases, so even at the correct angle, the edge bevels will be "taller" Now with a true wedge, which is to say one that is a close to fly gourd as humanly possible, you would not have that problem because you would be removing metal from the entire blade every time you honed.

Whenever I have honed my wedges, I have always used 3 layers of tape. Maybe extreme, but I like the smallish bevel it gives. I might try it with 2 some time or another. On my other razors, I usually use 1 piece of tape. Usually in the beginning so I do don't a lot of excessive hone ware like on the 1k. As I learn and play around more with I'll get better at it and know more about the science behind it. I'm sure some of yall reading are shaking your heads.....lol

Originally Posted by Willisf

Whenever I have honed my wedges, I have always used 3 layers of tape. Maybe extreme, but I like the smallish bevel it gives. I might try it with 2 some time or another. On my other razors, I usually use 1 piece of tape. Usually in the beginning so I do don't a lot of excessive hone ware like on the 1k. As I learn and play around more with I'll get better at it and know more about the science behind it. I'm sure some of yall reading are shaking your heads.....lol

Whatever works for you with honing wedges. If you download the excel file called Bevel Angle Calculation at http://www.coticule.be/wedges.html you can plug in the spine width and blade size to see how many layers of tape to need on a near wedge to get the proper bevel angle.

Bob

I forgot about that being listed on there.... Thanks Bob! I'll have to give that a looksie.....