Thread: Chosera Cracks

Last night, after a session I noticed cracks on my Naniwa Chosera 10k . I then found cracks on the 5k also.
The 1k is fine..

I soak both stones for a few mins before use. The 5k gets the longest soak whilst I set a bevel on the 1k.

I've never noticed these cracks before .... any ideas???

Thanks..

I have found Chosers stones to be splash and go,no need to soak. Soaking can be detremental to the binder in some stones. If yours are flaking or cracking try omitting the soak. Naniwa Professional Chosera 1,000 Grit

There's been a few threads on this before, some people soak them for a while and it has no detrimental effect. They are designed as splash and go so that's just what I do. I think once they start cracking there's not much you can do.
I remember Neil Miller having to send one back because it's started cracking when new and without soaking.
If it's not going down too far you could always sand it...

i use a 400 professional (successor of the chosera) for repair work and a 1k professional for bevel setting. both work fine, no cracks. i also had a 5k professional. although i never soaked it and used it with very little water it started to crack after a few months. as i liked the stone very much (except for cracking...) i bought a second one and used it with even less water. the stone is quite thirsty, so it felt like honing on a dry stone, which i did not like. anyway, this stone cracked as well after a few months. i replaced it with a 5k naniwa super stone. no problems since then.

the picture is of the second 5k professional. also note the ugly stains (the stone is dry)!

regards,
hans

The cracks are more like visual cracks rather than physical cracks.
I canrun my finger nail over them and feel nothing.

They are more prevalent on the underside .
I guess because the Shapton holder is wet with water and slurry .
There is lighter cracking on the surface of the 10k , didn't really show up well in my photos.
That's the one that bothers me. It only has say a 2 min soak before use then washed with a nagura under a cold shower.

Originally Posted by brightred

i use a 400 professional (successor of the chosera) for repair work and a 1k professional for bevel setting. both work fine, no cracks. i also had a 5k professional. although i never soaked it and used it with very little water it started to crack after a few months. as i liked the stone very much (except for cracking...) i bought a second one and used it with even less water. the stone is quite thirsty, so it felt like honing on a dry stone, which i did not like. anyway, this stone cracked as well after a few months. i replaced it with a 5k naniwa super stone. no problems since then.

the picture is of the second 5k professional. also note the ugly stains (the stone is dry)!

regards,
hans

My 10k is the Chosera ,the 5k is its successor andit looks patchy like your cracked stone , it also is thirsty .

Originally Posted by JOB15

The cracks are more like visual cracks rather than physical cracks.
I canrun my finger nail over them and feel nothing.

My 5k shows small cracks at the top edges and you can feel them with a fingernail. I wish I could give you (and me) some encouraging words, but I'm in the dark as it were, as much as you are. Whether these cracks will relegate the stone to an expensive paper weight, be inconsequential, or even if it can be returned for a replacement is unknown to me.

I do know that holli4pirating (SRP member) posted of his 1k Chosera developing cracks years ago. Mine, bought shortly thereafter never has. AFAIK he is still using his 1k cracks and all, with good results.



The first two photos are the honing surface with the cracks pretty much at the edges, while the last photo show the bottom with the cracks apparently all across the surface, but not deep. Cannot feel them with the fingernail. Seems to me to be a defect in the mix. Maybe the binder ?

wow im shocked ..welcome to crackville..

I will try to keep mine dry apart from a spritz on the surface pre honing ..

speechless

My theory is that the cracking occurs from too quick of drying. The stone seems to expand a bit as it absorbs water. If the interior of the stone absorbs water, then the surface is shrinking over an expanded center as it dries. I live in dry Colorado and dry my stones with a paper towel over them to slow the drying and keep the moisture content more even in the stones. I also use all of my Naniwas as splash and go and try to minimize water absorption while in use.

Originally Posted by bluesman7

My theory is that the cracking occurs from too quick of drying. The stone seems to expand a bit as it absorbs water. If the interior of the stone absorbs water, then the surface is shrinking over an expanded center as it dries. I live in dry Colorado and dry my stones with a paper towel over them to slow the drying and keep the moisture content more even in the stones. I also use all of my Naniwas as splash and go and try to minimize water absorption while in use.

I'd have thought the same thing.......... BUT ........... I've got the 1k,3k,5k, and 10k. All get the same treatment in use, and in storage. Only the 5k is showing the cracking. Crazy or maybe like Glen says ........ crazing ....