Thread: experiments

This is an interesting approach
Japanese Woodworking Forums :: View topic - Grit Tests on Natural Stones and Shapton

...just thought i would bring it to your attention. Maybe someone wants to help Alex out per his request, or share thoughts or photos. here or there I'll read it.

Now I want a nakyama even more!

Amazing pictures, Tim zowada has some similar pictures at his website.You can see some hefty scratchmarks from the shapton 30k there to.

Hey Kris that site is a place where you can catch up on japanese stone information. There isn't tons and tons of info, but there just isnt tons and tons of info anywhere on the web.

TEST#1
Please take a look at the third picture (30K Shapton). Pay special attention to the scratches on the unhoned body of the blade.
Now look at the 4th picture (Nakayama 1). It's obviously the same part of the blade same magnification, so the unhoned scratches on the body should appear exactly the same.

They do not. Someone is trying to favor the Nakayama. It does only take a minor adjustment of the lighting angle, to make a dramatic difference.
http://straightrazorpalace.com/advan...ent-light.html

I own a Nakayama myself, and I find it an excellent hone.
I don't own a Shapton, but I'm sure, based upon many testimonies of guys I trust, that it's an excellent hone as well.

I love science and scientific methods, even conducted by non-scientists with crude setups. But I hate it when bias is disguised as science.
On the same note, honing is about sharpening, not about scratching. How fine a hone polishes is only one factor contributing to its sharpening capabilities.

Bart.

Good observation Bart. The edge improved dramatically again by just by adding the ruler in the pic.

The other big problem is that at 25x those pictures aren't really even showing the results of the shapton or nakayama no matter what the lighting happens to be. They're showing the results of the hone that the bevel was set with. It takes an awful lot of honing with a nakayama or 30k shapton to hone down past grooves of those sizes.

In the Verhoeven paper he shows 3000x electron microscope photos of edges honed on a variety of stones and pastes, and the grooves from the 0.5 micron chrome oxide are surprisingly small even at that magnification. The Shapton hone that this Japanese site is talking uses abrasive granules about that same size.

Originally Posted by Bart

TEST#1
Please take a look at the third picture (30K Shapton). Pay special attention to the scratches on the unhoned body of the blade.
Now look at the 4th picture (Nakayama 1). It's obviously the same part of the blade same magnification, so the unhoned scratches on the body should appear exactly the same.

They do not. Someone is trying to favor the Nakayama. It does only take a minor adjustment of the lighting angle, to make a dramatic difference.
http://straightrazorpalace.com/advan...ent-light.html

I own a Nakayama myself, and I find it an excellent hone.
I don't own a Shapton, but I'm sure, based upon many testimonies of guys I trust, that it's an excellent hone as well.

I love science and scientific methods, even conducted by non-scientists with crude setups. But I hate it when bias is disguised as science.
On the same note, honing is about sharpening, not about scratching. How fine a hone polishes is only one factor contributing to its sharpening capabilities.

Bart.

Hi Bart. If i get what it is you are looking at, there is not an unhoned part of the blade. What you are seeing is the weld line between the hard steel and iron

Originally Posted by mparker762

The other big problem is that at 25x those pictures aren't really even showing the results of the shapton or nakayama no matter what the lighting happens to be. They're showing the results of the hone that the bevel was set with. It takes an awful lot of honing with a nakayama or 30k shapton to hone down past grooves of those sizes.

In the Verhoeven paper he shows 3000x electron microscope photos of edges honed on a variety of stones and pastes, and the grooves from the 0.5 micron chrome oxide are surprisingly small even at that magnification. The Shapton hone that this Japanese site is talking uses abrasive granules about that same size.

per Mr. AG. quote: "What I am photographing is the light reflecting off of the peaks with the contrast of the shadows in the valleys. "

So you can't really make an assessment of the size of the scratches. I am sure that just as he skews the blade when on the Nat stone to reveal a different pattern, there was a similar effort to be sure that only 30k scratches are left behind.

Note that the picture with the ruler looks much different than the picture above it. Evidently the position of something varies from picture to picture.

Originally Posted by Quick

Note that the picture with the ruler looks much different than the picture above it. Evidently the position of something varies from picture to picture.

Ah. This is only my opinion/impression from looking at the pictures and reading the text. The photo with the ruler is not meant as part of the continuum, only provided for a better sense of scale. The relative comparison is the progression from 12k to nakayama.