An Engineer's Blade Sharpness Study...

https://www.refinedshave.com/razor-blade-sharpness-summary/

Make sure you check the link to see how he is doing the testing. You may find it valid or not, but I could see his results starting some arguments on forums all over the world.

Thanks to Jan Martin at TSR for digging this up.

 

I have been thinking about exactly the same kind of test, and I am happy to see someone else been doing it.

The sad part is that this does not seem to work, because according to his results many blades becomes sharper from shaving. For example, Voskhod in his tests becomes sharper when used. From real shaving, I know I experience more tugging from a used Voskhod.

I wonder if an edge looking more like saw (a destroyed edge from shaving) is cutting his test media easier? Maybe he would get different result with another thread?

 

As far as two blades I use regularly(GSB&Voskhod) he's not telling me me anything I didn't already know, so it's all good.

 

Thanks for sharing, but I'll pass on viewing... I like what I like, and I'm good with that!

 

Far too complicated for me, it's a 10¢ blade.

 

I read a few of his reviews and he seems to link the idea of a blade getting sharper with whether or not it is PTFE-coated with the coated ones showing the increase in sharpness.

 

His test for sharpness is "push through" cutting.
It doesn't hold the blade at an angle to "slice through", if that makes sense.
All razors hold the blade at an angle. We tell newbies, "hold the razor at about 30 degrees to start, and adjust from there."
Even a str8 razor isn't to be held blade flat against face, but angled about two-spine-widths.
Does that make his results invalid? I have no clue, just something to consider.
While interesting, really it's too much science for me. I just shave and let face tell me if a blade is sharp, smooth, and comfortable.

 

Just about every blade I have ever used (as I remember it), gives me my best shave on #2. I always assumed it to be along the lines of a stropping, or smoothing out the rough edges so to speak.

I also didn't read all that far into it, but if you have coarse beard from your collar bone to your eyeballs, and shave with four passes, testing after the shave is likely not the same as after the two pass of the dude with the beard of a pre teen Swedish boy. I don't see that it negates his results. The blades still get sharper after a period of use. Maybe with your beard it is just halfway through the first pass.

I was more intrigued by the idea that some of the blades people almost universally call "less sharp", end up testing sharper than Feathers, which nearly everyone calls the sharpest blade in the universe.

 

I would think it is still a valid way to measure the keenness of an edge. It would tell you my boning knife is sharper than my bread knife, even though it wouldn't teach us anything about how well it cuts one product or another.

And yes, I agree with your last point. If your face doesn't like it, it doesn't much matter what a table says.

 

I Side with the curmudgeon on this one

 

Unless one concentrates on doing the Gillette Slide, aren't all whiskers cut by push through - meaning the edge chops straight through a hair at a 90° angle?

As seen on the graphic, during the Normal shave one point on a blade's edge chops through only one whisker at a time because the blade moves in a straightforward direction with no angle.

The G.S. is an angled swipe, letting a minuscule length of the blade's edge - not just one point of it - slice though a whisker. And the Tilt Slide doesn't "slice" any more than the Normal does...the blade is held at a different angle but the swipe angle is still 90°... one point, straight through.




So isn't most (Normal) shaving, regardless of razor, push through?

 

If the entirety of the blade (a str8 is easier to visualize) was laid flat against the face, I would agree "push through" the whiskers. But the blade is at an angle, even taking into account the angle of the bevel. Therefore I believe more "slicing" going on than "pushing." Flat agaist the face negates the bevel. And while almost microscopicly minute, the whisker would never be cut at skin level.

 

Hadn't considered the bevel. Will try to visualize this...

 

The test is valid in the sense that it is controlled and replicable. However, I believe what he is actually gathering data on is the thinness and shape of the bevel edge, in the form of the penetrating force required. He is assigning that data to be the nebulous thing called "sharpness." I feel validated though. Always thought Derby was pretty good. Again though, blades are far less important than technique. I've found that as my experience increases, the available range of blades that yield good results has widened considerably.

 

As his conclusions seem to agree with user observations on sharpness, Feather, Permasharp, 7'O-Blacks, and longevity, Kai, GSB, I figure there's something to his methodology whatever its flaws.

Sent from my Nexus 5X using Tapatalk

 

An artist I am not

 

And consider this - his device held the string taut by anchoring both ends. A whisker is anchored only on one end.

 

Does your face like the blade?- Yes
Use blade
As Inspector Clouseau used to say "Problem sol-ved".

 

One doesn't know which blade to try without some base of knowledge about the blade. I've learned to put near zero stock in user reviews, so this study is helpful in providing some data re sharpness and edge retention.

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