Thread: Which is sharper?

Originally Posted by frustratedSRuser

Which is sharper:

A well sharpened straight razor
or
A Feather razor blade in a straight razor holder?

Depends on what you mean by sharp, oddly enough.


Prof. Verhoeven examined commercial blades and a straight razor at 10,000x in an electron microscope and found they both had pretty much identical width cutting edges, and tricks like finer grit hones or pastes, and harder steel didn't really help reduce the thickness of the cutting edge much*. Extrapolating from this, a well-honed straight and a feather are almost certainly equivalently sharp if you're comparing the width across the cutting edge.

Unfortunately, the commercial manufacturers including Feather throw an additional complication in the mix. They coat their blades with low-friction coatings like teflon, which reduce the cutting friction and make them feel sharper (there's an article on the Schick website that talks about this). So even though the edge isn't any finer, it *feels* like it's finer. By this measure, the feather is sharper than a well-honed straight.

The best you can do with a straight is to polish the heck out of the edge so it is as frictionless as possible. This can get you to something that's about like day 2 or 3 on a feather super pro, and it only lasts for one shave before corrosion kills the polish and it returns to more mortal levels of sharp, but it's kind of fun nonetheless. A Shapton 30k followed by 0.1 micron diamond then a couple hundred laps on fresh newspaper will do the trick if you want to play with this sort of sharpness.

* Verhoeven doesn't address the implications of this. But if his findings are correct, then why do finer grit hones and harder steel seem to result in much sharper edges? Well there is some reduction in edge width, but not a whole lot, not really enough to explain the tremendous difference in sharpness between a 1k hone and 0.5 micron chrome oxide, or between a 57rc W&B and a 64rc Livi Takeda. IMO what the finer grit hones and harder steel really do for sharpness is they make it easier to get a higher level of polish which means less cutting friction and a sharper feeling edge. Smaller grit abrasives leave smaller scratches on steel, and harder steel takes smaller scratches from the abrasive.

Gentlemen,

In my modest experience and humble opinion, the Feather straight razor with replaceable blades must be the sharpest razor on earth.

I use the Feather only when traveling, although I am slowly switching to my regular straights even for traveling.

Yes, the Feather is sharp, but not frightening.

Regards,

Obie

Never tried a Feather myself but it sounds like it would be a good idea to pick one up just to use as a comparison against one's honing and polishing.

I've had some really super-sharp 5/8 full hollow Dovos but they forced me to be extra cautious during the shave. I don't know if it's the thickness of my whiskers or the blade losing sharpness quickly but by the 2nd shave those full hollows have to be pushed harder to slice through my beard. That extra force seems to always result in a nick or two. The ability to get one good shave only and then the start of nicks is just not a good trade in my book.

Here are some photos Tim Zowada took at 200x. The fact that the edge of the Feather has almost zero reflectivity compared to the others does make it stand out. No idea if that is directly related to sharpness or not.

I have a Feather and have used all three of the common types of blades produced for it. I have also used the Feather blades in an injector and a Classic Cobra. They are, for sure, about as sharp as you would ever want in a razor. At least they feel that way which may be a byproduct of their coating, as mparker points out.

It has been my experience that a few of my conventional straights will reach the same level of apparent sharpness as a Feather. They are all customs with very hard blades and well refined and polished edges (again, to mparker's point). One in particular seems to get even sharper than a Feather. That could be because Lynn played around with it with a Charnley, an Asagi and some diamond spray at the last NC get together and then I shaved with it. Whatever the reason, the thing gets wickedly keen.

Note that once a Feather has a few shaves on it the sharpness drops back to that of a really good shave ready straight and it is much smoother than when it is new. I find that I get a better shave with a conventional straight than with the Feather. They both give you a "sticky" smooth face, but the Feather shave starts to develop stubble sooner than the shave with a straight.

Originally Posted by Bill S

I have a Feather and have used all three of the common types of blades produced for it. I have also used the Feather blades in an injector and a Classic Cobra. They are, for sure, about as sharp as you would ever want in a razor. At least they feel that way which may be a byproduct of their coating, as mparker points out.

It has been my experience that a few of my conventional straights will reach the same level of apparent sharpness as a Feather. They are all customs with very hard blades and well refined and polished edges (again, to mparker's point). One in particular seems to get even sharper than a Feather. That could be because Lynn played around with it with a Charnley, an Asagi and some diamond spray at the last NC get together and then I shaved with it. Whatever the reason, the thing gets wickedly keen.

Note that once a Feather has a few shaves on it the sharpness drops back to that of a really good shave ready straight and it is much smoother than when it is new. I find that I get a better shave with a conventional straight than with the Feather. They both give you a "sticky" smooth face, but the Feather shave starts to develop stubble sooner than the shave with a straight.

I too have tried the Feather and the different disposable blades. The Pro Guard comes closest to a well-honed straight right out of the box. The other two are much more likely to cut you than any a regular straight. But even here, you can quickly get used to the sharpness (and the much flatter blade angle) and the weepers will stay away. After 4-5 shaves, the Pro Super shaves like a regular straight.

Some folks run the blade along styrofoam or cork to take away some of the harshness.

I used to think that the sharpest possible blade would be the best thing. Regular straights are better, in my experience, because they are quite forgiving and many of the different grinds give excellent feedback.

Certain straights !!!!!

I really think it comes down to that statement, There are certain straights out there that can get as "sharp" if not "sharper" then Feathers... As Mr Parker pointed out there is an absolute level at which the "thinness" of the cutting edge stops... Let's just say there are certain straights that reach that level....Or they reach that level of slickness or polish on the bevel that make them just a touch "sharper" then their cousins... Anyone who has honed a lot of razors has found them, in my experience they are normally American brands with extra hollow grinds....Oh yeah, and it is usually not all of that type, like not every single Green Lizard 131b or every single Shumate #850, it is like certain ones everything came together right with....