Thread: Does anyone NOT like Nakayama Edges?

Oh ah, the topic. Yes, I like the edges I get from my Nakayama.

I think Jim is working up the nerve to visit his local hone store, and drop some yen!

Originally Posted by Seraphim

I think Jim is working up the nerve to visit his local hone store, and drop some yen!

After all, he's been told he needs hundreds.

Can't start on that any younger, y'know. 20 or 30 would be a good start.

My personal paradigm for comparing hones:

First I hone the test razor (my test razors are 8 DA's from one batch) till it peaks on a Chosera 10K. I do this for several reasons. Till further notice, when it comes to raw severing power, I can't make a razor sharper than on the Chosera 10K. I have choise between several Coticules, BBW's, a Chosera 5K, a Nakayama, and a DMT 1200. I also recently tried a Norton 4/8K, a blue green Esher, and a mystery hone that was used as finisher at Henckels.
Please note that I am talking about raw shaving power, not about what I like best for shaving.

I spend a long time on the Chosera 10K, usually in the neighborhood of 100 laps, till the keenness maxes out and the bevel looks completely uniform at 40X magnification.
The Chosera leaves, by far, the most polished bevel of all hones I have used so far (There are unfortunately no Shaptons among them).

At that point I apply 2 layers of tape and produce a secondary bevel on the hone I am assessing for quality and sharpness.

Here's a picture of such a bevel. The secondary bevel of this one is also cut with the Chosera 10K and it serves as the standard for comparison.


All other razors are prepared in the same fashion, except that the secondary bevel is cut with another hone, of course.

The advantage of this approach is that the secondary bevel maxes out at the maximum keenness of what the hone in question can provide. Since the secondary bevel is only formed by that hone, all properties of that bevel can be attributed to that hone.

Thats how I compare between hones.

There are very little conclusions I can draw.

All Coticules and both Nakayamas I have tested all reach levels of smoothness and keenness that I find impossible to discern from each other. The differences are less than what is contributed by the steel of a razor.

As said, the Chosera is keener, but also harsher to my skin. At least with my shaving technique.

A BBW on water is not a superb finisher with this method. With a thin slurry it leaves a better edge, but slightly less keen than that of a Coticule or Nakayama with water.
With CrO slurry on top of the BBW, the edge resembles that of the Chosera 10K.

Most Coticues with slurry render an edge that I would not consider shaveready. Both Nakayamas I've tried left decent edges on slurry, but not as good as when I used only water.

I didn't have the opportunity to take any other type of hone through this procedure. The Henckels mystery hone is awaiting judgment.

In my experience, Nakayamas are great hones that produce excellent edges with little effort. If I was born and raised in Japan, I would probably have a website dedicated to them...

Bart.

Thanks for that contribution Bart. Excellent post

One thing about Japanese hones that hasn't been mentioned I believe is that similiar to coticules the grit size of the particles isn't really that relevant. Japanese hones have crystals which are similiar in shape to a potato chip that is why they create shallower cuts and also a flatter surface this is also the reason why they cut so fast instead of creating grooves they actually slice of any peaks that may be formed first and then just continue to flatten the bevel reducing its thickness rather than creating lots of grooves. I guess you could say that if you ran a fork through the top of a piece of butter it would do the same thing as some hones with sharp edges like diamonds and slicing the top off with a knife would be the same as using a japanese hone.

Originally Posted by Memorael

One thing about Japanese hones that hasn't been mentioned I believe is that similiar to coticules the grit size of the particles isn't really that relevant. Japanese hones have crystals which are similiar in shape to a potato chip that is why they create shallower cuts and also a flatter surface this is also the reason why they cut so fast instead of creating grooves they actually slice of any peaks that may be formed first and then just continue to flatten the bevel reducing its thickness rather than creating lots of grooves. I guess you could say that if you ran a fork through the top of a piece of butter it would do the same thing as some hones with sharp edges like diamonds and slicing the top off with a knife would be the same as using a japanese hone.

Very interesting. I didn't know that. I often ponder about abrasive particles and how shallowness of the scratches is more important than the width of the scratches. Coticules kind of offer proof of that, but I was unaware similar observations can be made for Nakayamas.

Thanks,
Bart.

Interesting visual there

Originally Posted by Memorael

One thing about Japanese hones that hasn't been mentioned I believe is that similiar to coticules the grit size of the particles isn't really that relevant. Japanese hones have crystals which are similiar in shape to a potato chip that is why they create shallower cuts and also a flatter surface this is also the reason why they cut so fast instead of creating grooves they actually slice of any peaks that may be formed first and then just continue to flatten the bevel reducing its thickness rather than creating lots of grooves. I guess you could say that if you ran a fork through the top of a piece of butter it would do the same thing as some hones with sharp edges like diamonds and slicing the top off with a knife would be the same as using a japanese hone.

That's a very interesting explanation. I'm no expert, by any stretch, but this seems to explain what I see in my microscope.