Thread: Bevel Level

Originally Posted by Jimbo

Just from a purely empirical perspective, I've never noticed any relationship between the width of the bevel and the shaveability of an edge, except (as others have mentioned) if you're talking about giving up a bit too early on a wider bevel because of lack of patience. But that's a honing issue, not a bevel issue.

A lot of the older blades I have - 1810 - 1850 - are the old-style wedges with fairly huge bevels. These shave just as well, if not better, than some of my newer blades with almost imperceptible bevels like, say, the Wapis.

Personally, and I'm certainly no expert, I think shaveability is simply related to how close to a point you can bring the two sides of the bevel at the edge. Plus, of course, quality of steel.

James.

The more I hear the more i'm inclined to feel that I have made an error. However both these are full hollow not wedges- but ddd has nothing like a wide bevel Seraphim showed. obviously though they would by nature of the beast behave differently from the get go.

Originally Posted by kevint

The thin line of the edge does know what's behind it I think, that's how 10degree angle cuts easier than 40 even if both edges ended with a true 0 dimension both equally "sharp" but supporting geometry creates different behavior.

We were talking about bevel width, not about bevel angle, weren't we?
Of course bevel angle does matter. But a wider bevel doesn't automatically mean a steeper angle. There's no immediate way to tell which one of your two shavers has the steepest angle, and even then, within the typical range on razor's cutting angles, all instances can be made to perform outstandingly. From what I read in your first post, I don't think your Double Duck shaves outstandingly.

Originally Posted by kevint

The width cannot be a marker for flex, as Russ said you need to know the thickness of the near edge steel, the overall width, and spine thickness. A true flat side wedge would be all bevel and not very flexible.

Agreed. If you look at a bevel as a miniature version of a wedge, than a wide bevel is stiffer than an equally wide part of a razor with a narrower bevel. (unless we consider convex edges too) But it would only be a very small contributor to the total flexibility of a razor. That said, I don't really see how flexibility is related to sharpness.

Originally Posted by kevint

Finally why wouldn't flex be a positive or negative feature depending on its value. An overhoned wire bur is balking at the hair, not because it is blunt but because it is too thin. (?) flexing or has my imagination run away from reality.

That is highly speculative. I think that overhoning happens when the ratio between edge width and honing particles allow for the honing particles to eat parts of the very edge, in such way that the edge starts to fall apart. Bending stresses are part of the process, but they are not related to the kind of flexibility English was talking about.

To add another data point, I have often noticed that a lightweight razor is much less forgiving to a slight lack of keenness that a heavier blade. I think that is due to inertia. I also think that "the weight factor" outweighs "the flex factor", but that's something I can't back up.

yes I may have gotten off task there somewhat referring to angle rather than width. But instead of thinking about the full spectrum of possibilities of multiple razor types, what I am considering; changing the angle to steeper incline with multiple tape layers will narrow the bevel. the edge should the become somewhat less flexible as the supporting geometry will be thicker. which may not mean anything conclusive if there is some honing flaw that could be more easily corrected... ultimately though what could have been is less important to me than getting this duck to cut and it's never done that well with what i've done so far

Kevint,

I think you have a 4/8" razor in its prime and a DD that when new was 6/8" and now is 5/8".

If you don't like the DD feel there is nothing you can do about it. It is what it is.

If you look at the blade from the front you will see a Y shape. Look at the two blades and see if you can tell which should be the more flexible blade.
also if you consider that the DD used to be a 6/8" blade and is now a 5/8" blade, you can imagine how much of the thinner part of the blade has been honed away.

Playing with tape will not effect the geometry in the way that the past honing has reduced the flexible part of the blade.

Some like this stiffer type of blade. If you don't, just move it on to a new home were it will be cherished and cared for another 50 years.

Originally Posted by kevint

I don't have a weeks worth of razors so I have few to compare and contrast.

I have a 5/8 DD dwarf that was used long and hard judging by the flat on its spine. not perfectly even, not extremely wide but an obvious flat around 1mm+ I taped and honed it, while the bevel does not appear out of line to many I've seen here- but it gets near the point where you might call it wide

I try to compare to a 4/8 Shumate BdL. Practically new used condition, only the faintest touch of honing on the spine with a corresponding teeny tiny bevel.

Between the two I much prefer the shumate. It cuts cleaner, quicker, closer than the dwarf.

Admittedly I did monkey around with the DD maybe too much. I've honed it twice and last time with a single layer 3m 35 tape enough to reset the bevel with this new angle 1000 to the 5 to the 8. stropped it at least 3 times since. no hints of wire under the scope

It shaves. But the shumate shows me how much better a shave can be. My other raz also has a smallish bevel. After my initial learning curve I set it aside as it too is pretty new looking and cost me alot more to aquire so that's my collection. (the rest are in the rehab bin waiting for me to stop yacking on the net)

Oh yeah the question. How does bevel size effect shavability and edge life in your experience?

It doesn't affect the shave one bit at all, now for edge life I have found that slightly steeper angles (1 layer of tape) last longer, to just answer your questions, of course as with everything in this hobby,,, YMMV

Originally Posted by English

Some like this stiffer type of blade. If you don't, just move it on to a new home were it will be cherished and cared for another 50 years.

Good call, it's all about what suits your personal tastes.

As for re-honing it, if the blade doesn't take an edge with the stock bevel angle, adding tape won't make it better all of a sudden. It might make the honing go faster if the angle is too steep but there's no reason you should have to use more than one layer of tape.

I do appreciate greatly your time gents. I believe I will listen to the advices as I re honed on a much finer stone last night and got a much better shave. At the moment I am growing more beard to see if the shumate is improved off the same stone.

English if you don't mind re-explaining the proper way to measure: "For me the true BLADE width is the measurement between the blades edge and the edge of the honing edge closest to the blade edge."

Just to be sure I follow, then I can measure it properly.

Its full width near the middle is 13/16 approximately

I think I can explain what English means, but if I get it wrong, by all means correct me.

If you look at Seraphim's razor, there is about 1/8 inch or so of material on the spine that does not touch the honing surface. The effective width of the blade stops at the polished surfaces on the spine because anything beyond that point is superfuous and does not effect the cutting angle.

It has more do do with accurately measuring the bevel angle than anything; the width of the spine at the polished areas and the distance from those areas to the edge of the blade define a triangle that has a specific bevel angle. If you were to include the portion of the spine beyond those polished spots in the length measurement, the calculation would give a different, and inaccurate, result.

So to be completely accurate, if that blade were an 8/8, the mathematically useful measurement would be more like 7/8. But for the sake of convention, you can label it 8/8 since some roundness of the spine is expected.

Correct this if needed. The overall width between the polished surfaces(thus in contact with the stone) outside to outside , equals razor size.

Originally Posted by kevint

Correct this if needed. The overall width between the polished surfaces(thus in contact with the stone) outside to outside , equals razor size.

Hmmmmmm, in some people's and some (few) manufacturer's opinions, Most of the NOS razors that you find with actual sizes marked on them, were measured from the top of the spine, to the edge of the blade, thus the overall width of the blade.....