Thread: Any experience with Suehiro Gokumyo Hones?

Referring to the 20,000, anyone know if they have a polymer based binder ? Do they require lapping every time before use ? Some polymer based binder stones do IME.

Do you mean resin binder like shapton?

Originally Posted by DaveW

Do you mean resin binder like shapton?

I heard, ..... don't 'know' for sure, that the naniwa and the shapton pros are polymer based. I don't know about the shapton glass. A former member here who is a scientist in the field of polymers told me that. He said that because polymers are affected by temperature, humidity and what have you, that they will move to some extent. So that by the time you get around to using them again they need to be lapped again. I am wondering if that is the case with this stone ? It was with my superstoes and my shapton pro stones but not with my nortons or with my chosera 1k.

The choseras use a magnesia binder (I don't know exactly what that means, other than smooth stones that can't tolerate indefinite soaking), and the shaptons use resin. They may both be polymer types, but are a lot different in feel (you probably know that already). Some of them do flex (superstones have a bad reputation for it, but I had one and didn't notice much because it was in a controlled environment). I've never had choseras or shapton pros flex an amount that I could detect (with tools, where the flatness is vital for the back of an iron), but mine are glued to kingwood.

I would assume that at the hardness, the gokyumos are either vitrified stones (like the old style india stones are) or resin bound. Vitrified stones can be soaked forever, I think, and i'm pretty sure shapton says not to do that with their stones though they do state in their instructions that a 10 minute soak is beneficial.

I'm not a stone expert, though, just a pig with a problem. But not a big enough problem to buy a gokyumo at this point.

Originally Posted by DaveW

The choseras use a magnesia binder (I don't know exactly what that means, other than smooth stones that can't tolerate indefinite soaking), and the shaptons use resin. They may both be polymer types, but are a lot different in feel (you probably know that already). Some of them do flex (superstones have a bad reputation for it, but I had one and didn't notice much because it was in a controlled environment). I've never had choseras or shapton pros flex an amount that I could detect (with tools, where the flatness is vital for the back of an iron), but mine are glued to kingwood.

I would assume that at the hardness, the gokyumos are either vitrified stones (like the old style india stones are) or resin bound. Vitrified stones can be soaked forever, I think, and i'm pretty sure shapton says not to do that with their stones though they do state in their instructions that a 10 minute soak is beneficial.

I'm not a stone expert, though, just a pig with a problem. But not a big enough problem to buy a gokyumo at this point.

My pros and my superstones would change from session to session. When I was new and dumb enough to drink the kool aid, I was so concerned with flatness that I bought a Starrett # 385 `12" machinist's straight edge. I would check for flatness with that and my superstones, the ones that were thick with no base, would need lapping before each session and so would the pros. Not the nortons or the chosera 1k. If the 20,000 gizmo is of that ilk I would start thinking about it. Otherwise I'll keep suffering with my yellow green escher. Truth is, I'm not as concerned with flatness as I used to be but at least some semblance of flat.

Originally Posted by JimmyHAD

Referring to the 20,000, anyone know if they have a polymer based binder ? Do they require lapping every time before use ? Some polymer based binder stones do IME.

all I know is that the 20K is a ceramic based stone. What binder, if any, is unknown to me.
What I can say though, is that my 20K has been lapped once.
After a couple hundred razors up and down that thing it is still flatt as can be.
This hone is hard as a diamond plate
I have submerged it throughout a honing session, used it as a splash and go stone, and even honed dry with it.
It is stable as can be.

What I will do though, is clean it of after honing several razors at one sitting.
For that I use a couple laps with a Shapton DGLP, which seems to do all that this hone will ever need in regards to flattening.

How does it compare to the Shapton 30K?

Originally Posted by leadingedge

How does it compare to the Shapton 30K?

I can only speak of the difference between the Pro version Shapton 30k and the Gokumyo, as that's the Shapton I have.
IMHO the difference is minute, but if I had to pick just one of them, the Shapton would have had to go.
I have never had anything but the most wonderfully sharp and smooth edges off of the Suehiro. The Shapton pro is great too though.

Originally Posted by leadingedge

How does it compare to the Shapton 30K?

The particle size is the same at 1/2 micron (and shaptons are very closely graded, as too probably are any stones of that expense level).

I talked to stu a little bit before these stones were listed and he told me he was going to list something that would make a shapton look soft.

It's probably cheaper at exchange than the shapton pro 30k, too, which is, to me, inexplicably expensive at $400 or whatever it is now discount (I know some places still list it for $500 or $600). 1/2 micron abrasive isn't uncommon, so I can't fathom why they charge that much when a 1 micron stone is a little over $100.

Originally Posted by JimmyHAD

Otherwise I'll keep suffering with my yellow green escher.

Sounds like you're roughing it! I wish I could say I had an escher. Also not that interested in super flat for razors, either. It's pretty easy just to look at what's going on with the razor bevel to find out if the stone is addressing the entire bevel on each swipe. If it is, especially on the finest stone, there's no reason to get excited and waste stone and time.