Yunzi Stones With Kaya Board - bad idea?

[deepgreen]

I know ideally, a Hon-Kaya board should be paired with
stones that are shell & slate. But can Yunzi Stones
be used? OR ...

Is Kaya too soft, and too easily damaged by Yunzi?

[EdLee]

Have you had any experience with "lesser" boards with yunzi ?
For example, a shin-kaya with yunzi ?

[deepgreen]

Yes, but only with a hard board (like bamboo). Not
with Shin-Kaya. I'm not excessively rough with stones ... but
wasn't sure if Yunzi stones are a bad idea, and would quickly scratch
and dent Hon-Kaya - and/or how careful one would need
to be.

Have you had any experience with "lesser" boards with yunzi ?
For example, a shin-kaya with yunzi ?

[jts]

Aren't yunzi stones much closer in price to slate and shell than a cheap board is to a kaya board? It seems cheaper to buy the nicer stones than to worry about the damn board.

Certainly all stones will wear down any board eventually. Ceramics are about 7 on the Mohs scale, shell I assume is similar to calcite at 3, slate is a composite of very soft minerals with a few quite hard ones - I'm guessing that on the whole it's similar to the shell. But how much faster will a 7 create scratches and dents versus a 3 or 4? Is hardness even the right metric?

[deepgreen]

Point taken. I asked because I already own
a set of Yunzi that I really like and was
hoping to keep using 'em when I get a Kaya board...
but then started to wonder if they might be
too hard.

Where are the best places to get a good
deal on quality shell & slate?

And, what's the most recommended stone
size for Japanese boards?

[csobod]

Point taken. I asked because I already own
a set of Yunzi that I really like and was
hoping to keep using 'em when I get a Kaya board...
but then started to wonder if they might be
too hard.

Where are the best places to get a good
deal on quality shell & slate?

And, what's the most recommended stone
size for Japanese boards?

I honestly don't think they would be too hard. Actually, it's the height of the stones that makes the biggest difference. Taller stones are more convex and have a smaller point, meaning the pressure of putting it on the board is distributed on a smaller point, heightening the chance for dents. Stone height is the key, here. So how big are your yunzi stones?

[gogameguru]

And, what's the most recommended stone
size for Japanese boards?

Assuming you've got a standard sized Japanese board, you want stones that are 22 mm in diameter (about 0.87 inches).

[deepgreen]

csobod - thanks for weighing in. My Yunzi's are 9.2 mm

[csobod]

Thanks for weighing in. My Yunzi's are 9.2 mm

Well, ideally you'd want something as flat as possible to give a larger surface area to distribute the pressure of placing them. 9.2mm is fairly flat, I'd only really err on the side of caution with 10mm and up. You can actually see a visual comparison here:



Notice how flat the 7.5 and 8.0 stones are? That's really your ideal for minimizing potential damage. Anyway, I hope this helps. I'm by no means an expert, so just do your homework and go with what you think is right.

[deepgreen]

Nice little chart. Thanks for posting that!

[gogameguru]

I think maybe we're getting our wires crossed with thickness and diameter. 9.2 mm sounds like the thickness of your stones (it's a very common size for stones). Yunzi come in several sizes. Yours are quite likely close enough to the right size (in terms of diameter), but there are also slightly smaller ones on the market (less than 20mm).

The thickness of stones is (usually) just a matter of personal taste, but csobod makes a good point if you're worried about denting a soft board. Are these single convex or biconvex Yunzi you're talking about?

[deepgreen]

Ooops. Quite right. My mistake. My Yunzi's are
Size 33 double convex 9.2mm tall and 21mm wide/diam.

I think maybe we're getting our wires crossed with thickness and diameter. 9.2 mm sounds like the thickness of your stones. Yunzi come in several sizes. Yours are quite likely close enough to the right size (in terms of diameter), but there are also slightly smaller ones on the market (less than 20mm).

The thickness of stones is (usually) just a matter of personal taste, but csobod makes a good point if you're worried about denting a soft board. Are these single convex or biconvex Yunzi you're talking about?

[gogameguru]

In that case, your stones sound like they're the right size. If it were me, I'd wait and try the stones on the board once it arrives. Just be gentle when you place the stones. Any softwood board will eventually be covered in small dents with enough use, even if you use slate and shell stones on it.

Slate and shell stones are usually matched with kaya primarily for aesthetic reasons. The other reason is that shell stones - especially the typical, cheaper Mexican sourced shell stones (which chip and crack easily) - are easier to break on harder boards (e.g. Agathis, Katsura). So usually you'd use something like Yunzi on one of those boards.

If it just comes down to taste, it's your go set. If you like your Yunzi, keep using them.

[deepgreen]

Thank you David, appreciate that. That eases my concerns.
And I may just keep an eye out for a deal on shells &
slate over at KGT.

[skydyr]

I thought the potential issue with yunzi stones and a soft wood like kaya was that the yunzi stones have a rougher finish, which can scratch the board when slid. Am I mistaken?