Crazed Shapton

[Russell Sansom]

On the recent Neanderthal thread called "Complete my Shapton Setup" a discussion arose about crazed Shaptons and the American vs. Japanese formulation of these stones.
For the sake of posting a photo which would have been off topic on the other thread, here's my 8K Shapton "Professional." In a moment of mental lapse I washed it with hot water. At least I hope that's the reason it self-destructed.
This isn't just surface glaze, it is fractured. Why it hasn't fallen apart is a mystery, but I'd guess it's only a matter of time.
BTW, the writing on the case and on the face of the stone was Japanese, so I guess this was not the "American" version. I don't know which is which.

[george wilson]

I've had razor stones that got that way,but didn't fall apart. They might be different composition,of course.

I just thought this was part of the "Japanese tool craze." :)

[David Weaver]

On the recent Neanderthal thread called "Complete my Shapton Setup" a discussion arose about crazed Shaptons and the American vs. Japanese formulation of these stones.
For the sake of posting a photo which would have been off topic on the other thread, here's my 8K Shapton "Professional." In a moment of mental lapse I washed it with hot water. At least I hope that's the reason it self-destructed.
This isn't just surface glaze, it is fractured. Why it hasn't fallen apart is a mystery, but I'd guess it's only a matter of time.
BTW, the writing on the case and on the face of the stone was Japanese, so I guess this was not the "American" version. I don't know which is which.

Epoxy it to a piece of glass or a quartersawn piece of water-tolerant wood. It'll hold together fine. I don't think it's in danger of coming apart looking like that, though, it looks superficial.

Maybe they really do make them for the japanese market with the assumption they'll be in a higher humidity environment?

[Russell Sansom]

Definitely not superficial. You can see one deep fracture in the middle and another on the right. There are more, but didn't have the opportunity to do a fancy photo setup that would show them properly.

[george wilson]

My razor stone was 2 layered. Better epoxy it down to a piece of thickish aluminum or glass,like David suggested.

[Jon Toebbe]

And this was just from washing it in hot water? Yikes... I was just given a Naniwa SuperStone set as a gift (how great a LOML is she?). Is this something I need to watch out for, or is it Shapton specific?

[Steve knight]

I have a set of hippo stones (shapton no longer makes them) they are crazed and it has not been a issue for years.

[Russell Sansom]

The hot water probably did it. I'm almost certain I read somewhere not to expose it to direct sunlight, hair dryer...and I'd guess hot water. I suppose I've developed a mind set that all these kinds of warnings are just legal CYA. I take it as an expensive but probably useful mistake that will have me thinking a little more carefully about manufacturer's warnings. Even if it's a chore to separate the technical signal from the corporate noise, it can't hurt.
It wasn't my intention to spread worry at all. I have no idea if this is something others need to be concerned about. Except for the questions David asked about the significance of Shapton's "American" formulation, I haven't read of other incidents like mine.

[Stuart Tierney]

How hot was the water and what temperature was the stone?

Are we talking a summertime incident where you used hot from the tap water, or something like the stone being very cold and dunked into boiling water?


I am VERY interested in this, for more than just curiosity. I'd especially like to nail down which 'stone' it was.

The US market stones have an English language label, a different letter in their number (a K instead of an N, I think) and that's about it visually. The Japanese market stones have a warranty disclaimer sticker, or they used to, then it disappeared when there were no US market stones, and I am sure it will re-appear again.

If the stone is more than 3 years old, and there are remains of a sticker on the base/case, then it's Japanese. If it is less than 3 years old, then it's probably Japanese or old stock US.

I am so interested in this stone, that I'd almost be willing to replace it for you, not with a Shapton though.


The ironic thing is that the climate in Japan ranges from full tropical to nearly Russian winter, very dry to extremely humid, and yet the Japanese market stones are supposed to be not up to snuff for the rest of the world? I've never understood that, and do plan to investigate further.

Heck, I have 3 Shapton stones, all #1000 grit. No, I don't plan on using them for my own personal amusement... :eek:

[Derek Cohen]

Hi Russell

I have an 8000 Shapton that resembles yours. I bought it a few years ago on eBay. In addition to the crazes, the stone would move slightly when it dried over night. As a result, I epoxied it to glass ....

http://i13.photobucket.com/albums/a262/Derek50/Sharpening/Shapton1.jpg

This fixed the movement. I have never experienced any issues with the crazes.

http://i13.photobucket.com/albums/a262/Derek50/Sharpening/Shapton2.jpg

Regards from Perth

Derek

[David Weaver]

The ironic thing is that the climate in Japan ranges from full tropical to nearly Russian winter, very dry to extremely humid, and yet the Japanese market stones are supposed to be not up to snuff for the rest of the world? I've never understood that, and do plan to investigate further.



This is what I was thinking. On average, japan is probably more humid. There are places in the US that are more humid than places in japan if you pick right, and I would imagine the list would be numerous.

The humid parts of japan are probably a lot like pensacola or houston in the summer, or most of the gulf coast, but I don't know what the winter in japan is like.

Thanks to Russel for taking the time to take a picture and post it when I posed this question.

[James Taglienti]

What on earth?! No hot water, no direct sunlight... what is it, a Gremlin?

I hope they at least cut nicely, when they're not squirming around as they dry, or self-destructing because a ray of sunlight hit them. Good grief.

[Russell Sansom]

James...
I wouldn't extrapolate quite that far. The Shaptons , wed to a Tormek to get a hollow, suit me perfectly ( I used arkansas / silicon carbide for decades before they came along ). They always do what I want and they cut predictably. Each grit has its own personality, of course. This 8k is the only one that went crazy on me. For me, the don't-have-to-soak water stones were a step back through the looking glass into a world of rational grit increments. But, keeping the thread on course...

...to Stuart's question from Japan: I bought this stone about 3 years ago. As I recall,all the writing on it was in Japanese. There was a sticker on the "bottom" that left a shadow until I flattened it. The bottom of the case has Japanese writing.
The temperature question: It started around room temperature or a little cooler ( 65-75 degrees F ) and I used tap water as hot as my hand could take, say 140-Deg F.

[Derek Cohen]

What on earth?! No hot water, no direct sunlight... what is it, a Gremlin?

I hope they at least cut nicely, when they're not squirming around as they dry, or self-destructing because a ray of sunlight hit them. Good grief.

Hi James

With the exception of the movement I reported above, once epoxied to glass, this stone has been stable and utterly reliable. I did not wait, and went and did the same for all my other Shaptons Pros (1000, 5000, another 8000, and a 12000), and they all perform exceptionally well.

The pros of Shaptons - do not need soaking, cut fast, remain flat a longer time than other waterstones, and have a hardish construction (which promotes greater feedback).

Perhaps the glass should be a standard feature - do others experience movement after the stone dries?

Regards from Perth

Derek

[Sam Takeuchi]

My Japanese Pro (Ha no kuromaku) #8000 is the same. But it only appear on #8000. Not on #5000 or #12000.

I don't think hot water is the cause as my stones never been exposed to hot or even warm water. It's pretty solid so I haven't really paid much attention. It sharpens just as well.

[Gaz Palmer]

Ceramics can often develop micro-fractures during the firing/pressing process and don't tend to have the same complex layering as that found in natural sedimentary stones. On that basis, I'd tend to assume synthetic reinforcement of some kind - as found in a various types of ceramic tile and pressed brick paver - may have been added during manufacture if flawed examples haven't separated/fallen apart. :confused:

If reinforcement were used, the slab could be pre-stressed during manufacture and capable of remaining intact in spite of full depth flaws. Very similar to pre-stressed concrete beams.