Thread: Does anyone NOT like Nakayama Edges?

Let's see. I have a Nakayama Maruichi, The surface of the stone is like glass. It's really in a class by itself. I have 4 Escher's, Shaptons, Coti, Naniwa's, Nortons, DMT's, Barber Hones, C12k, close to 50 rocks. You get the idea. In finishing, nothing compares. Now, there are differences in Japanese Naturals and I don't think a Charnley Forest, or even a Tam come close to the edge supplied by Nakayama. The closest you'll come to feeling it, would be an Escher. I have gotten some of my smoothest shaves off Escher's. Nakayama too. I've spoke to Lynn many times on this subject, and he can correct me if I'm wrong, this was a while ago, but his top two finishers were Nakayama, and Escher very close behind...If you can't afford a Nakayama, you probably can't afford an Escher, but that's what I'd tell you to try. Both are comparable in price these days, You may get an Escher a little cheaper, but O_S has some good deals out there. It is hard to put in words, but you get that velvet squegee feel people talk about, You get sharpness, without harshness, A very sharp comfortable shave, and you can shave right off the stone. Of course I strop, but no need to do Crox or Diamond, nothing.

Originally Posted by Visibility

p.s. Here is a photo comparison to explain what i'm talking about. I have the two stones to compare and the photo's are 100% accurate. Under a scope, that is what the difference in the edges is.

TEST#1

I remembered these photos from a previous thread. (This one: http://straightrazorpalace.com/advan...periments.html)

The conclusions then were that the photos were a little misleading. For instance Rajagra pointed out that the ruler scale shows one centimeter rather than one millimeter as claimed.

Originally Posted by matt321

I remembered these photos from a previous thread. (This one: http://straightrazorpalace.com/advan...periments.html)

The conclusions then were that the photos were a little misleading.
Rajagra pointed out that the ruler scale shows one centimeter rather than one millimeter as claimed.

I thought they looked familiar. Those seem to come up every year or so. The photos are labeled as 25x, which is what I based my comment above on. Also, I notice that the website those came from sells nakayama but not shapton. While this may be because their careful analysis of the hones has led them to the conclusion that the shapton is simply inferior, it nonetheless means that their claims and those photos should be taken cautiously, even before you notice the obvious problem that the size of those scratches don't match the hones they're supposedly testing...

also, there have been some comments in this thread about using chrome oxide after a high-grit finishing stone. With anything at the level of a coticule or better you shouldn't need to use chrome oxide, heck even the lowly norton 8k will produce a fine shaving edge. Certainly you should insist on getting a beautifully sharp, smooth shave directly off any of the stones we're discussing in this thread, the shapton, nakayama, coticule, and escher. If you're using a nakayama or S30k and chrome oxide is improving your edges then you need to revisit your honing technique, because both of these stones are the equal of .5 micron chrome oxide.

I bring this up because there's a definite tendency to want to buy better tools and toys, but at some point the tools don't matter nearly as much as the hand that's using them. Once you get to the coticule or escher or beyond, then you're really better off mastering whatever hone you've got than you are flitting about from hone to hone trying to find the ultimate hone. Or strop, or razor, or brush, or soap, golf clubs, etc.

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.

There is no doubt that the lighting/razor angle is different in the Nak photo, it also appears to be zoomed out a bit.

But when I look at it at home, where I can experiment with the lighting and such it's a similar phenomon, that's all I'm saying.

Just for educational purposes, I'm curious what makes you say that the Nak is releasing larger particles. It seems like you are saying it's releasing some larger than .5 micron, which may or may not be true, I just want to pick your brain a bit.

Originally Posted by mparker762

Sure. I have a couple of microscopes as well. And I see similar sorts of scratches, depending on the angle of the light. But what I'm seeing are *not* the scratches from the shapton 30k - they're the scratches from the lower-grit hones, brought into sharp relief by the polishing action of the shapton which polishes the tops of the high ridges. In the photos you linked to, notice that in the shapton shot there are large, fairly contiguous areas on that bevel that look a bit flattened and polished, where the grooves aren't as prominent. There are three irregular bands of these going across the length of the bevel, one at the very edge that may be a microbevel, and two more farther back on the bevel. One or all of those bands is likely where the shapton is honing - my suspicion is it's the one at the edge itself, because...

The nakayama-finished blade actually has a rougher edge - don't look at the bevel, look at the edge itself - there is a distinct regular sawtooth pattern on the nakayama edge that isn't present on the S30k edge. This again demonstrates pretty solidly that neither the nakayama nor shapton edges were effectively sharpened on those hones, and that the edges are still hopelessly compromised by the remnants of their 1k honing striations. Verhoeven demonstrated in his paper that when viewed under an electron microscope, blades only show a regular sawtooth pattern up to about 2k grit, beyond that the edge gets thin enough that the steel at the edge is simply too weak to sustain the sawteeth. When I compare edge roughness between hones, I set the lighting and contrast so that only the reflection off the edge shows up, this reduces the distraction of the bevel appearance since all you have to look at is the thin white line interrupted by the occasional microchip. Any sawtooth pattern that is showing up means that I need to go back to the 4k or 8k hone and clean things up before going back to the finishing steps.

The real reason the nakayama bevel looks "finer" is the loose particles in the slurry are rolling around underneath the bevel and leave behind a finish that under magnification looks like it's been sandblasted, and this changes the way the light reflects off the surface minimising the appearance of the underlying low-grit scratches. If those edges had been honed properly then neither razor would show any grooving pattern at all at that magnification, there would be no sawtooth pattern at the edge. From looking at those partially-honed bands on the S30k picture, you might predict that the properly-honed S30k bevel would look like a mirror (and you would be right), and from looking at the sandblasted-grooves on the Nakayama picture you might predict that the Nakayama bevel would look like a sandblasted mirror (and you would also be right).




Sorry, but unless you've got a microscope at least 1,000x, then what you're seeing aren't the scratches from the nakayama or shapton, and I'm doubtful that even at 1000x that an optical microscope could resolve scratches of this size.

Secondly, while it's true that the particles from the Nakayama are always breaking down, it's also true that new large particles are always coming out. So this isn't a win-win scenario - those small broken-down particles may well be smaller than the ones on the Shapton30k, but those new fresh particles coming out are larger than the ones in the Shapton. And I've never heard anyone claim that the particles in the Shapton don't break down. Certainly on mine it gets finer and finer over repeated uses after I've lapped it, which makes me think that the abrasives are breaking down as well.





I don't think you're dissing shapton, I just don't believe that those photos you linked to are particularly useful except as a negative example.

I get similar levels of sharpness out of my shapton 30k and nakayama asagi. If either is superior it isn't by much, certainly not enough to worry about since there are ways of getting much higher levels of sharpness. So if I'm going for sharpness I really don't care if the nakayama is 10% or even 30% better than the shapton, because the edge is only gonna be there for the few minutes it takes to haul out the newspaper or 0.1 micron diamond or 0.05 micron aluminum oxide.

Originally Posted by OLD_SCHOOL

To try and head this thread back on topic. Are we to understand Jim, that you do not like the edges you are getting from your hone?

*sigh*

Had to let the cat out of the bag, eh?

well, I honestly think that's a topic for another thread...

So...to another thread!

Originally Posted by Visibility

Just for educational purposes, I'm curious what makes you say that the Nak is releasing larger particles. It seems like you are saying it's releasing some larger than .5 micron, which may or may not be true, I just want to pick your brain a bit.

I don't know for certain what size the nakayama particles are before being released and broken down. I've read on this forum back when Ivo showed up with his Kiita that they are roughly 1-2 micron "in the hone" but I can't find that post so I could well be misremembering. Maybe oldschool knows.

They're unlikely to be much smaller than 0.5 micron though or these hones would be much slower and much finer than they are. If the 40k grit number is correct, that's only 33% finer than the shapton, and presumably that 40k grit number is some sort of average of the particles in various stages of breakdown, so assuming the particles break into more than two pieces before being discarded then their original size was likely at least 1 micron.

Here's an thought experiment to illustrate what I'm talking about. Assume for the sake of argument that the original particle size is 1 micron (it makes the math easy), and that the particle fractures twice before it is lost or otherwise ceases to contribute to the honing effort, and that we are examining a sufficiently small part of the hone that only one particle is released every so often.

At time 0 the stone releases one particle of 1 micron size. At time 1 it releases another, and the first particle breaks down into two pieces. At time 2 it release another, and the other particles break in two again. At time 3 the same thing happens except that the fragments of that original particle are lost over the side or finally pulverize into nothingness. At this point we're in a steady state with three sizes of particles, the original particles coming loose from the hone, particles that have broken once, and those that have broken twice. That gives us:

1 1.0 micron particle
2 0.5 micron particles
4 0.25 micron particles

The total size of the particles is 3 microns (since these came from three 1-micron particles), and there are a total of 7 particles. The average particle size is 3/7 = 0.42 micron.

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.