Thread: Sharp blade: harsh v. smooth

How would you explain: two blades are sharp, however one gives a smooth shave, another one is rough and skin is irritated?
Mind, I don't hone myself
Thanks.

What are the two razors and what are they finished on? Tc

Take your imagination to the microscopic level and look at the edge. So at the edge you have a 12k finish and it is sharp but harsh feeling. Now when you look at the grain tips of the metal they are all lined up and sort of look like a saw blade. Some longer than others some farther apart. This is because the grain your at breaks some in half and some that are right next to each other. SO, now imagine you take that edge to a smooth stone with almost no difference or much less of a difference in size. The ends of those grains are going to line up closer together. It is now going to feel smoother because you have less of a saw blade effect.
Now there will be others who can explain it differently and even point you to electron microscopic pictures. And you also have other things to consider like blade thickness and the type of hollow in the face.

From my minds perspective that is a simple explanation you may be able to grasp.

The size of the grit and the shape of the bevel. Not to mention your style of handling the razor are all factors the give everybody a different perspective. Some like hollow some like wedge. I think most will agree the finer the grit the smoother the feel.

One razor is a Gold Dollar, rough & irritating; the other razor is a Wade & Butcher, smooth & close.

Originally Posted by tcrideshd

What are the two razors and what are they finished on? Tc

It's was more kind of metaphor: Shaved today with Ralf Aust, new, 6/8 and it was rough. No idea about the finish. But yesterday it was Bengall and it was great. Both were sharp, but apparently it's not everything.
Ilya

Originally Posted by 10Pups

Take your imagination to the microscopic level and look at the edge. So at the edge you have a 12k finish and it is sharp but harsh feeling. Now when you look at the grain tips of the metal they are all lined up and sort of look like a saw blade. Some longer than others some farther apart. This is because the grain your at breaks some in half and some that are right next to each other. SO, now imagine you take that edge to a smooth stone with almost no difference or much less of a difference in size. The ends of those grains are going to line up closer together. It is now going to feel smoother because you have less of a saw blade effect.
Now there will be others who can explain it differently and even point you to electron microscopic pictures. And you also have other things to consider like blade thickness and the type of hollow in the face.

From my minds perspective that is a simple explanation you may be able to grasp.

The size of the grit and the shape of the bevel. Not to mention your style of handling the razor are all factors the give everybody a different perspective. Some like hollow some like wedge. I think most will agree the finer the grit the smoother the feel.

Originally Posted by ibixon

It's was more kind of metaphor: Shaved today with Ralf Aust, new, 6/8 and it was rough. No idea about the finish. But yesterday it was Bengall and it was great. Both were sharp, but apparently it's not everything.
Ilya

I think 10Pups answer is ultimately on the money. But there are all kinds of ways to get to those nice edges.

For example - I have a Boker that just takes a killer edge. Off my 10K Nani, the thing slices hairs before even touching it's that sharp. But the first shave or two are notoriously harsh if I don't work it hard on the strop. If I finish it on a natural, one that's famous for round granules, I get a much nicer edge - or a smoother edge. So on and so forth.

That's all to say that you have to figure out what the blade likes sometimes. I used to call it voodoo, but microscopes prove otherwise. Fun if you're a scientist, but experimenting and voodoo have their place too lol.

Thank you guys. I've been always skeptical about the hair tests;- it's kind of voodoo to me, and as we know sharpness does not necessarily gives a smooth shave, but strong strop definitely makes sense. And microscope. For those who hone.

There are also tremendous variations in steel composition and in heat treatment that will have a major effect on the performance of razors.

For me, I'd say the harsh one was finished on diamond paste. I find it too harsh. A few passes on CrOx will smooth it out. Or more laps on leather.

Wipe that leather strop off from time to time. After you or your wife sweeps the bathroom. A tiny grain of just about any thing hard can cause micro damage to the razor's edge. I have had it happen to me and I could not see it with my eyes. I had to go Sherlock Holmes with a giant magnifying glass. Which still wasn't so easy to spot and I had to re hone the razor to fix the problem. Good luck