Thread: Natural Japanese waterstones

Well done, Wilburpan.

Just to start somewhere, I mostly use only natural waterstones. I have a water-cooled Jet grinder -- no heat; waterstone wheel -- and some man--made stones for rough work. But once I've got an edge to where I want it, I much prefer the natural stones. My understanding is that the longer you work the edge, the more the grit compresses, thereby becoming finer. So I have one rough stone (no idea grit comparison, but it cuts about as quickly as my man-made 220 stone, though I'm sure the grit is higher) which I know only as "zebra stone." And a couple of medium and fine stones, though I rarely need the fine if I've cleaned up a blade nicely the first time: a healthy touch-up on the medium (probably around 8000?) and good go on a suede strop with green rouge, and it's in fine fettle.

Becky

I wanted to be able to go from rough to finish on natural stone. So collected a few of the various stones available (mostly from ebay).
In my opinion, (thus far - am no expert), man-made water stones do a faster job in the rough grits (200ish), faster in the lower mediums (800-1000) and about the same in the finer mediums (1200). These are the man-made grits I have.
I'm still playing around with binsui, iyoto and aoto to see where they seem to fall grit-wise compared to man-made 4000 and 8000. Compounding the problem, of course, is the variation in steels I have amongst various tools (none of them I know for sure what kind of steel - can make an educated guess that chisels are going to be white steel. I have one kanna that is supposed to be tamahagane). I have a variety of fine finish stones, but have still not used them often enough on all the tools to know which work best and when I can go from medium to finish (when its optimum). Regardless, I get my edges sharp eventually.
The natural stones enhance anything visible in the steel, which I like to see.
No question about the best edges from the awase-do, though.

Steve

Stolen from the ground
My tools grinding at the stone
All are worn away

Ooops - I have also just started a new thread on this topic. As this thread is already underway (by over an hour..apologies, Wilburpan) I will cross link that thread to this one. If you would like to see what I posted, here it is.

Neil

Neil:

Since yours is the only post so far on the other thread, how about reposting it here? That way we can keep the whole thing in one place?

Regarding your post, as said above, I use natural stones almost exclusively. I took a chunk of money and made some nearly random purchases, and I'm pretty happy with the results. And So is right:
"Using natural stones will enable you to plane thinner (more sheen on the surface of the wood) and at the same time it will make the edge last longer."

That's certainly been my experience. And his explanation supports my (limited) understanding: that the material on the natural stone compresses and gets finer and finer as you sharpen, so that you can achieve with one stone what you would have to use two, maybe three stones to accomplish with man-made.

I've tried to write the names of the stones I buy/have bought on the sides of them -- unfortunately, they're out in my shop right now -- so as to keep some sense of, well, what the hell I'm using... but the truth is I just don't seem to retain it. I just reach for the stones I've learned are best for a given application, and go to work.

It does take time, and a bit more finesse. Most of these stones need careful truing before use, and are very fragile. I bought a hunk of what I referred to in upthread post as a "zebra" stone (all I know of it) -- which is a very effective coarse grit -- and dulled a number of saws cutting it down. Then trued the piece I cut. Within a few days, a crack appeared in the stone. Right across it.

I've reinforced the sides with water-soluble lacquer to try and hold its integrity, which so far is working, but it really is maddening to work so hard to cut the stone, true it, and days later find a crack.

All that complaining aside, now that I've gotten comfortable with these stones, they're my absolute favorites. I tend to use the man-mades on my Western tools, and save the naturals for my Japanese tools.

Not so much because of the like/like factor, but because I tend to sharpen the Western tools with far more haste.

Any of this coherent? Useful?

Ah, well... tired.

I have two natural stones. The first I bought about 2 years ago from Carba-tec. It is Chinese rather than Japanese. My experience has been quite negative to date. It is really hard, and I am not sure what it is supposed to be doing! Does anyone here also have one, and if so will you share your experience.

The other is a Japanese waterstone that Lee Valley had (perhaps still have) on a run out sale. It was about $45. I have only just begun using it, but so far my experience is positive - it has a soft feel compared to my Shaptons and hones quickly. I cannot say what grit is but the guys on the Japanese Tools forum speculate that it is about 20000. (if one could measure a natural stone, that is). Wilbur, I know you have one of thse as well. What do you think?

Regards from Perth

Derek

Hi Derek,

I have two of those LV stones. I've only used the smaller of the two (I can't yet bring myself to erase those lovely stamps on the bigger one) and also really like it. It is fairly soft, but extremely fine grained (probably not the finest available) and puts great edges on my tools.
One of the aspects of natural stone, is the fact that they sometimes have inclusions which are harmful to the steel (areas harder and larger in size than the average grit, so make a nasty scratch). Best way to ensure these elements are either non-existent (no absolute guarantee) or pose a minimum risk, is to buy from someone who knows natural stone (pretty much everyone who has a business selling Japanese tools and such on-line. They either know stones themselves, or obtain their stock from a reputable supplier) or is honest about those that may be more risky or are known to be contaminated to some degree.
I bought two stones off ebay (both from Nakaoka-san [Mifuqwai]) which were el-cheapo because of the (as he describes it) "toxic" flaws. If you want to take the time to locate these toxic areas and remove them (just carefully dig them out to a depth slightly below the surface, same as would be required if a "safe" stone unexpectedly uncovered some) you will be rewarded with a useable finish stone. Of course, the digging out will have to be periodically repeated as the flaws sometimes extend right through the depth of the stone. I don't know how often stones like this will be available, so not necessarily an option. But its definitely worth the higher cost to obtain a natural finish stone and I don't think we will hear of many who don't find the better edge worthwhile.

Steve

Hi, Derek,

Steve's information is real good.

I also have an extremely hard waterstone (from Nakaoka-san) -- Japanese, not Chinese -- and I have to say I find it pretty useless except for a really high polish. Really, really high. It refines the edge further (though at that point, I'm just not sure, even given my compulsive nature), but you have to be so careful -- it's very unforgiving -- that it becomes quite tiresome to use. I find I can approach this quality edge by longer work on a lower-grit (still very high) stone.

Yeah, Steve -- what's up with all that gorgeous calligraphy on the stones? It kills me every time I have to lap it off. Sometimes -- usually if I don't have a whole lot of information on the stone -- I'll snap a photo of it for future reference, in case there's some crucial information there I'll need later (hasn't happened yet: just me being compulsive again).

Derek -- the other thing about those super-hard stones is you have to make sure it's abolutely flat, or you'll never get a good feel for where the blade is -- I'm sure you've had my experience of the blade feeling as though it's more skating over the surface than actually being sharpened by it.

Becky

Hi Becky and Steve

The only other person I know who has that hard Chinese stone is Philip Marcou (plane builder), and he has been exhorting me to use it as he likes it. So I am curious.

I know what you mean about "flat" being important with hard stones. The last time I flattened it with a 10" Extra Coarse DMT diamond plate. It did not make any difference. I now have a Shapton diamond lapping plate, but I doubt that this is going to do it for me.

What I want to know is whether you use a natural stone, such as the LV finishing stone, after a manmade finishing stone, such as a 8000 or 12000 Shapton, and why?

I suspect that the answer is "grit is not grit when it comes to natural and artificial".

Regards from Perth

Derek

Well, here's the rundown of the natural Japanese waterstones I have:

From mifuqwai, on eBay:

Aoto stone: This is a medium stone, probably like a 3000 grit

Okudo Asagi finishing stone - this is really hard, and dark gray in color. It's so dark that I can only tell that it's removing metal by the fact that after I'm done using it, and the water dries up, I see very fine rust colored bits on the black background. I bought this one mainly because it's big.

Ohira finishing stone - I bought this mainly because it was really cheap, since it was about half the size of a small-sized finishing stone. This was my first venture into natural Japanese waterstone, and is also on the hard side, but not as hard as the Okudo stone I have.

From Lee Valley:

One of their closeout finishing stone specials. This is softer, much like what Steve and Derek describe. By the way, it looks like that the closeout specials aren't available any more.

Both the hard and soft finishing stones do a great job on the tools I have. I'm kind of split as to which one I like better. To complicate my life some more, I bought another softer finishing stone from mifuqwai recently -- it hasn't gotten to me yet.

I have a friend that has bought some really high end stones from So at japan-tool.com. I need to find some time to go up to his place and check them out, and see how they compare to my budget specials.

I've bought from LV on that close-out special (haven't tried it yet).

Several from Nakaoka-san. A couple from Alex Gilmore (I'm pretty sure...). Some from So.

I also have coarse, medium, fine, and superfine man-made stones.

On the whole, I'm much happier with the edge I get on the natural stones. (Still haven't gotten out to workshop at the same moment I remember to make note of exactly what I have...) I find the edge lasts significantly longer; they need truing less often (except for the coarse grit, which wears down fast); and they impart that (as I've opined before) lovely kasumi haze. Which, of course, has nothing to do with performance (as far as I know -- any opinions?), but is aesthetically really pleasing.

Given the tough work I've subjected many of my nomi to lately, I'd have to say the natural stones give an edge that holds at least -- at least -- twice as long. And, as mentioned here (or was it elsewhere?), I can touch them up very quickly with a suede strop and green rouge (whose idea was that oxymoronic name?).

The man-made stones are fairly durable -- I find they don't need flattening all that often, and are blessedly free of random inclusions. But no matter how fastidiously I work them, I just don't get the same edge in the same amount of time. I have to believe the "the longer you sharpen, the finer the grit" theory of natural stones accounts for this.

The important thing to remember is that 800-8000 grit man-made stones can be stored in water (not good for 220 or 12000, e.g., on the other hand), but the natural stones should really only be wet down slightly, and as needed, during the sharpening process.

On some natural stones (the harder ones, mostly -- which may partly defeat the purpose), I like to use some nagura stone in order to reduce that skating feeling I mentioned before. Just seems like a more solid bond between stone and bevel.

I find I need nagura on almost all man-made stones.

So, yeah, Derek: grit is not grit. And yet, it is: just a constantly diminishing size. I have yet to be able to guess at a comparison between my man-made and natural stone grits.

Any chance So might weigh in on this and enlighten us? Or Alex? (Or is Alex on the other forum? I'm losing my mind -- I mean memory...)

Yours in galloping senility (at a shockingly early age!),
Becky

Derek,

I have both a 4000 and 8000 man-made stones. But as I understand it, I should be able to go from a "medium" natural stone like iyoto or aoto to a natural finish stone, and that's what I've been doing (with satisfactory results I think). So I suppose my wanting to know how these stones compare to each other grit-wise is just academic. I don't plan on putting the man-made finish stones in play before going to the natural finish stone(s).

Also, with respect to sealing the natural stones, I use Mod Podge (sometimes called Podgey). Its cheap (sold in craft stores and used as an adhesive or sealer top coat on things like paper one wants to waterproof. It dries quickly, but does not form a hard, brittle skin, but rather flexible) and non-toxic. It smells a lot like PVA glue (looks like it too) and can be thinned with water. My binsui stone lost a large chunk along a fault, but I just Pogied it back on and so far, no problem.

Steve

p.s., one thing I've found (as you all probably have) it that too much water on the fine stones causes the blades to skate and slip and chatter (even on the softer stones). A slurry always seems to help, so maybe you guys with the hard stones, you need something to create a slurry (or maybe less water?). I just dip my finger and spread it on a small area (I don't try to wet the whole surface).
Another thing (now that I'm on a roll) that for me ensures an flat bevel (I don't use a guide) is to put the blade on the stone, feel when the bevel is flat and only push it away from me (cutting edge leading of course) for a short distance, not trying to make a continuous stroke down the whole length (regardless of the grit of the stone). I found that trying to extend the stroke too far (arms too far out from the body) imparted either a rocking motion (rounding the bevel) or losing the feel of when the bevel was flat (it could be, but not sure). When I reach the end of my short stroke (happens all the time), I completely lift the blade off and don't try to slide it back, even with lighter pressure. Not the world's most efficient sharpening technique, but works for me. I also work across the surface of the stone not only along its length, but diagonally and even perpendicular to the length. Using the short strokes this way helps keep the surface from hollowing (I'm sure it would howl if it could.
Stay tuned, I'm sure I'll think of something else.

"green rouge (whose idea was that oxymoronic name?)."

A girl that does wood working and has really nice tools. Great. But green rouge! I mean, really.

I just can't picture it,
Steve

p.s., I am kidding, Becky.

Have tried Harrelson Stanley's side-sharpening technique; find it almost impossible: but then, I'm so used to working with the wide edge of the blade parallel to my body, or just slightly skewed.

Like Sheets, I tend to work in small strokes, though on the coarse stone, I'll work in longer strokes toward me to gain even pressure and cut larger amounts of metal. When I get to the finishing stone, I'm much more conservative. Also like Sheets (and who wouldn't like Sheets?), I tend to work the bevel around the surface at all angles and into all corners. Same reason: more even wear on the stone.

When flattening the burr on the back (if I get one -- and sometimes, superstitiously, even if I don't ), I use the long edge of the stone, just in far enough to insure good flat contact.

On a different note, I use the sides and corners of the stones for gouges and parting tools. (Really wish my gouge sharpening technique were better -- any help here?) Not always, but generally. Or I'll cut a piece of a stone and shape it to fit. I have some man-made cones and other shapes, but -- as noted before -- I never feel I have the same excellent contact and results as with the natural stones.

Have I fallen so far in your estimation that you must tell me you're kidding in a pathetic attempt to shield yourself from my Wrath? Hang on... fallen... estimation... See, that sentence started off in one direction, then hung a sharp left. Take two: Am I so far fallen in thy estimation that thou now must needs stoop to inform me whence thou art making of me such keen mockery? What sayest thou, Bedsheets?