Chosera specifically: 5k and 8k snow white

[Kawa]

If you want a stone to dry evenly, which I assume might help prevent cracks, turn it regularly during the drying process.

That means flipping it, top becomes bottom and visa versa.

During the first minutes of drying you can see why. The top side of the stone dries first while the bottom is still wet.

The more time goes by, the less I flip them. Starting like 10 minutes, 20 minutes, 1 hour, 3 hour, before bed, next morning. Dry in the evening.

 

[Kawa]

I'm well aware my point of view is not generally accepted. Sealing is a very bad answer to possible problems, as they find their origin in poor, incomplete drying. Once the inner part of the stone has got wet and stays so, its structure changes and will expand, making the outer layers to crack.
Most problems did occur with the first generation Chosera, thicker, and with a standard. That standard hindered full drying of the bottom.
The next generation, the Naniwa Professional, was thinner, and had no standard. Composition if possible even denser in abrasives. Haven't seen any problem with them. Don't expect them with the newest Naniwa Chocera Pro.
In the time of the first generation it was commonly advised of course not to soak it, but to apply a layer of water and wait for a while, raise slurry with the nagura and apply water again. No good idea.
Not sure if getting both the 5k and the Junpaku Snow-white 8k makes a lot of sense.
Both can be used directly after a 2k, or even the 800, depending on the kind of edge you're looking for. The Junpaku offers some surprising refined bite — which the 5k doesn't.
You may consider as well the Shapton Pro 12k, which delivers a similar result in the 7k range with the same bite without being that fussy.

Interessting.

I thought going from Chosera to Professional (thicker, with nagura) was a form of shrinkflation.

So the thinner stone might be the better one for anti-cracking

 

[kayman67]

Except it's really not. Still happening. Made no difference.

 

[Benuser]

Interessting.

I thought going from Chosera to Professional (thicker, with nagura) was a form of shrinkflation.

So the thinner stone might be the better one for anti-cracking

As does the absence of a base.

 

[Kawa]

Except it's really not. Still happening. Made no difference.

No one here has enough chosera experience (done enough experiments) to say it doesn't reduce the chance. There are so many variables.

They will still crack sometimes whatever you do, you know that from reviews.

All those little things you can do to 'better dry a stone' added up, it's about reducing the chance on cracks. I hope




edit: ow wait, you're talking about the reducing in thickness (chosera vs profiessional) only, right?

 

[kayman67]

Yes.
They are popular even in Europe, sold quite a few and been around enough now to draw a line and see what's what. But regardless, here somewhere at some point someone explained how it's a binder issue. We just try to get around it in various ways. So far the epoxy "fix" worked and that's it for me. Won't advise anyone to baby these further.

 

[Mr Kooby Shemayrew]

OP, what are you sharpening and what are you looking for?

I have had my Naniwa Pro 800 and 3000, and neither has suffered any cracking.

I can't say anything about the 5000 myself since I have no experience with one, but if it's been an issue for you, then have you checked out alternatives? I've heard good things about Morihei 4000 and 6000, and you might also check out relevant Shapton Glass stones.

For 8000 I currently use the Naniwa Fuji 8k (it's a resinoid stone, and very much a "bright-polisher". I use it as splash-and-go.) and I like it. So far I only ever use it for things like low-alloy carbon-steel single-bevel knives or else a white #1 gyuto.

I also have the Naniwa Hayabusa / Falcon 4K and Fuji 8K, and I use them almost exclusively on straight razors. They both finish well above their stated grit ratings. The 4K is more like a 6K, and the 8K is more like a 10K.

I do have mine sealed on all sides except the front face. No issues with cracking - but this series is not known for having any cracking / crazing issues.

The feedback is “plastic-y” and muted which some don’t like. I feel it but it doesn’t bother me. They finish very uniform and consistent. Very refined edges on razors. For knives they finish too refined and do not leave enough bite. For that reason I tend to not use them with knives.

For me these two stones are sold at my local hardware store and they are inexpensive.

For razor work, the 4K is great. I often go from this to a JNAT. No need for additional steps. The 8K would be very redundant with a 10K Shapton so I would not recommend that.