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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..
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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
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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. :(
My 10k is the Chosera ,the 5k is its successor andit looks patchy like your cracked stone , it also is thirsty .Quote:
Originally Posted by brightred
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.Quote:
Originally Posted by JOB15
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.
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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 :ziplip:
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 .... :boohoo:Quote:
Originally Posted by bluesman7
I thought I would have a go at lapping the cracks from the surface of my 10k Chosera .
Using my Shapton diamond plate I did 10 mins or so which revealed that the cracks are worse than I thought, much more prevalent.
Also whilst the water dried from the surface I could sea the cracks drying before the non cracked parts .
The 5k I can let go of or buy a new one but the 10k cost me an arm and a leg. I was sure that the 10k would out live me.. Maybe I will be forced to go back to my Shaptons?
I know the 10k can be used dry, maybe that's the answer? kinda feel cheated to be honest .
A thought just occurred to me that you might not want to hear :(
I really haven't had an issue, my 5k had a bit of crazing but I flipped it and haven't had an issue since
BUT
My Chosera hones are used "Professionally" basically near every day, when they are not in use they are face down on a towel that is probably damp..
Basically they hardly ever really dry out except 2 separate weeks out of the year..
:shrug:
IDK maybe the wetting and complete drying is bad for them
Glen, it is really hard to figure. Mine are rarely used. I just don't hone that often, and when I do I may use other alternatives. I do a 5 minute soak, use the hone, into the dish drainer and when relatively dry, and the session is done, back into the kitchen cabinet. All of the hones are laying on their side, about an inch apart from each other, in a clean and dry dark space.Quote:
Originally Posted by gssixgun
All are treated exactly the same yet my 5k is the only one to exhibit this phenomenon. That is why I'm wondering if it isn't a binder problem of a particular batch ?
It has been a mystery for some time, and really mostly about the 5k
Color me confused Jimmy
I posted about my 1k cracking a (long) while ago. It never affected the performance, so I didn't worry about it. Still true. Granted, I would prefer to have a hone that didn't crack, but I'm not worried about it.
(Never soaked it, but sometimes the 1k sees prolonged use. I thought it may have been from rapid drying in the dry, cold Rochester winter, so I wrapped it in paper towel or actual towel after use to try to slow/even out the drying process.)
I, when new to the sport, left a few hones in water over night....bad idea. The Polar Bear/Kings got a white rime on them when they dried and still work but....
My 1K Chosera is cracked across and somewhat spider webbed. I read somewhere that the binder used is different from the ones years back.
The cracks have not caused trouble. But the appearance is a mess!
I have had to return a couple of the King/Polar Bears due to really bad segregation of grits. 'Bought from a Big name wood working supply house.
So, ugly or no, honing is as honing has been.
If bought at retail store return for another one. If not. Your descendants will probably still be using the hones.
~Richard
I always seal the sides with lacquer to prevent issues.
I think this is spot on.Quote:
Originally Posted by gssixgun
I never dry any of my ceramic stones . In fact I just give my Shap Pros a wipe with a sponge & put them back in their plastic boxes.
Only recently acquired a 1k & 5k Chocera & they get the same treattment ie a simple wipe down.
The only crazing I've had was on a 12k Pro that was left in a sunny spot.
Some Shapton instructions I lifted from the net. As I said I treat all ceramic stones this way. The old Clay based types are bombproof.
Do not leave stone in water. Doing so may damage the stone. To use the stone, just splash water on it as needed.
Do not leave stone in the sun. Store the stone indoors, out of direct sunlight, instead.
Do not dry the stone with a fan. Doing so may cause hairline cracks to appear on the surface of the stone.
Do not subject stone to extreme temperature. Store the stone indoors at room temperature.
Do not wash stone with hot water. This may damage the stone. Use cold or lukewarm water instead.
Do not wash stone with soap or detergent. This may damage the stone. Use water instead.
Shot in the dark.
If the stone can hold water.
Stone originally cut from moist rock and dries out and checks/cracks after being exposed to the air much like fresh cut lumber.
Sounds good aways. Har!
I am on Cracked Hone Train. I did leave my 5K in water for hours (ER visit).
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Even if you had to keep spraying your Chosera, it beats the pants off a sloppy Norton.
My hone is holding. Hone donated divot of self, see lower right of 5K, into water. lapped and ran with it.
It is a well kept secret but 5k choseras with cracks, like mine, are known to be the best razor hones ....... rivalling Eschers and J-nats .... :rolleyes:
Why you both dont contact Naniwa and the japanese to replace the defective stones Or contact seller
Professional stone - a pound of dollars prise and - keep away from watter and sun No way
Send email to Naniwa directly and show them the problems
Amazing fact, I will trade you my GS20. :)Quote:
Originally Posted by JimmyHAD
LOL ! Good one ........... :rofl2:Quote:
Originally Posted by sidmind
