Thread: My new Japanese stone

I got this one and really confused me a lot. i have done at least 25 razor on this stone finally made my mind what is it and how to use it.
what was wrong this stone makes fine edge but all of a sudden half of the edge approximately 1.5 inch length was just broken off. it was not saw tooth etc just looks like laser cut. Finally i find out what is the reason. the reason was fault iron line.
Stone is from reputable seller but he didn't put any stamp etc on this stone. i assume because of it does have big fault iron line or this stone has more problems hidden which i have no idea yet.
it cuts very fast and i used after 1k. brings edge approximately to 16k level in less then 5 minutes. after that you can use another finer Japanese hone or EScher and blade will be shave ready.
i would recommend this stone to person who hones a lot blade. will help you get it done faster.
Definitely not for new starters. 1.5 kg huge stone.
hope this helps.

what kind of stone is that?
some weird Nakayama?

Originally Posted by mainaman

what kind of stone is that?
some weird Nakayama?

I have no idea. i know only name started with "O"

Originally Posted by hi_bud_gl

I have no idea. i know only name started with "O"

I think Oohira, but filling the gap from 1k to ~16k is quite impressive.
Hope the stone does not have other issues, enjoy.

Hard to tell which mine it came from, remember most mines contained similar strata although the grit particle sizes can be vastly different. The main issue with this toishi is the heavy inclusion left running across the larger portion of the stone. These are normally made up from a different mineral content that migrates through the rock as seepage, mineral disolved in water. Sometimes the material is harder and will scratch the blade, other times softer, but in anycase it was not a mineral original in the formation of the strata.

I suggest that you use epoxy to attatch the smaller piece back on, and do the same when and if the other inclusion seperates. Use a slow setting epoxy, not the 5 minute stuff. In Japan they use urushi, a natural lacquer derived from a type of poison sumac, but the urushi would cost you more than the stone originally cost. Better now then later to make this repair.

Stones are graded in Japan partly on the regularity of the grain. This would be considered by most standards to be a lower grade stone because of the inclusions, and if the grit is as you say this would also be a consideration. That said, a lot of sharpeners are looking for medium grit naturals with good abrasive powers as a step in the progression. If you are finishing with a natural stone, no matter the origin, another natual before that I feel is a good combination. Alx

Are you sure it's a name? In Japanese, 'O' sometimes denotes 'large' and is used as a prefix

Originally Posted by alx

I suggest that you use epoxy to attatch the smaller piece back on, and do the same when and if the other inclusion seperates. Use a slow setting epoxy, not the 5 minute stuff. In Japan they use urushi, a natural lacquer derived from a type of poison sumac, but the urushi would cost you more than the stone originally cost. Better now then later to make this repair.

Alx

Alx,
Does it take value away from these gems to laminate a piece of naural slate in a tasteful way? I noticed that some of them are presented glue onto cypress. Thanks.
Mike

Mike

For your own use, disregarding resale value, laminating a stone to another stone sounds like a good idea, many european stones are like that. Glueing on to cypress is something else.


I myself would rather buy a stone that I can look at from all sides. If a stone for sale is thin, say less than 10mm then you got to figure that the stone has a limited lifespan in the years, not decades. And in this case a base could be an option. The problem with that is thin stones are more fragile and being still a stone somewhat rigid while the wood base on the other hand will with changes in temperature and humidity shrink and warp. This may jepardize the stone.


I think an expensive stone of any thickness glued to a wooden base is taking a chance. I say this with the hope that I am not offending anyone here as a reader, but this is something to consider. The proper way to mount a stone is so the stone floats in a custom fit carved out cavity, there should also be drainage usually in the form of channels to the sides, and the stone should fit in a still manner without any jiggling from side to side which would put undue pressure on it from below. You should also be able to lift out the stone periodically to clean under it.

Some stones are so good and fine and match your steel so well that it is worth using them until they become little pieces. You can glue them up and mount them, but with diminished size comes diminished value so as far as reselling them that is a factor. If you have a good stone take care of it like a baby, if it just an average stone get as much use out of it as possible and in any way as possible. Even little flakes and chipped off pieces can be used to polish little tight corners or areas of rust as finger stones or to use as slurry stones. In the end the value of these stones is in the use. Alx

I don't know anything about using epoxy on a fault like that, but when a stone is cracked a bit, it seems like you could make it perfectly functional by simply preventing the blade from touching the cracked area.

For example, why not take a strip of fine sandpaper and wrap it over something round, like a pencil eraser, then lightly trace back and forth over the crack a bit? This would both lower the level of the undesirable minerals in the crack and round the edges so that the blade would pass right over it without catching on anything. I don't mean making a big canyon; you'd only need to drop it a smidge. Sanding it enough to make a functional difference would probably be barely visible.

I think i will end up splitting the stone in 2. to take out fault line. What happens at the moment i use only half of the stone and it is not comfortable. if i split it then i don't have anymore fault line and edge will be fine. will not broke down.
just thought,