Waterstone reality.... an Asagi of Indeterminate Origin (AIO), part 2

Slurry slurry slurry...... A funny sounding word in its own right, and it just gets MORE odd when you use it.

DMT #1200 slurry.

This is new territory for me, in terms of natural waterstones. My finest stone is a koppa (piece or splinter, sort of) Ozuku asagi, but this stone is finer yet and the action is smoother without being soft. Really easy to use and FAST, for its grit. I thought that the Ozuku was relatively fast, but THIS waterstone is about 4x faster! When I close my eyes and touch the Ozuku, I think of a blackboard, a writing slate, cold, sharp. When I touch this stone, I think..... cool, firm, a hard surface dusted with powder...

I want to try this stone with the ODC, but first I need to go back and do a bit more ground work..... and a reality check.

T=30sec. each stone (I'm not hardcore or anything).

This is the "ink" stone and the Ozuku asagi, using the ODC nagura. The slurry on Inky has oxidized to more of a gray/brown, but it was black a few seconds ago. The slurry of the Ozuku is still black. I am concentrating on polishing just the steel, so I am using a stroke parallel to the cutting edge.

When I use the ODC, I give the stone just a few swipes, barely enough to see. It is a VERY mild abrasive and as the ODC breaks down, it seems to expand about 10x in volume. Strange stuff.

T=15sec.

Even stranger..... With this stone, the slurry forms but only gets a bit darker, a gray tinge. "Normally" the ODC breaks down and quickly turns black with iron particles. With this stone, the slurry just sits there, as though the stone isn't working..... VERY interesting!

I THINK that what is happening is this......

A typical natural waterstone is composed of a range of particle sizes that are mostly larger than the particles of the ODC. The smaller ODC stuff acts as a cushion or filler, reducing the metals exposure to the abrasive. As the ODC degrades, more of the base stone's surface is exposed. In effect, the largest, most jagged particles are buffered by the ODC until they are worn down to a common size with the other abrasive grains.

 The slurry is the worn and degraded particles that have been dislodged from the parent stone. They both abrade the tool steel surface AND the stone surface as they get ever smaller.....

This stone behaves differently, with the ODC slurry at least. Magnify the last drawing 10x....

This stone seems to have an average particle size that is slightly SMALLER than that of the ODC. The ODC is masking or preventing the steel from making contact with most of the parent stone. Only a few particles are larger than the ODC, so they would be responsible for the slight darkening in color of the slurry. 

I feel that this is significant. I think that I have found the practical limits of the ODC nagura. This speaks well of both this stones quality AND the utility of the ODC nagura. WAY cool!

T=15 sec. 

No nagura and almost no slurry formation, but the stone doesn't feel super hard and is quite friendly. That dark patch on the upper left corner of the stone is basically all swarf. Amazing.

Full mirror on both steel (hagane) and iron (jigane). This blade is harder than most and somewhat special.

 Different blade, still good, but not AS hard. About as hard as my daily "users".

T=15 sec

I set the bevel to the stone, close my eyes, and slowly "guide" the blade. You can "feel" the stone remove the metal. I haven't felt ANY scratchy bits yet, not even the two dark spots. 

This bevel is reasonably flat and, if you look close, you will see some rust pitting but almost no scratches left over from other stones. 

Like I said, this is new sharpening stone territory for me, and I think that I know why.

Alex Gilmore at The Japan Blade  has a few stones that look similar, like this beauty....@$2,100!

Nakayama Maruka awasedo ttoishi

Here is my AIO again.

Very similar, especially the skin, although his are stamped and have a known provenance. If you go to his site (Item Nakayama #19), you can watch a video of his stone in action. The speed of metal removal is comparable to mine.... incredibly FAST!

I must admit to a certain degree of , not scepticism but maybe uncertainty, about how GOOD these old Toishi were/are. These old premium stones are an order of magnitude better than anything that I have used to date.

This is my A-team grit progression.... Inky, Ozuku, and AIO.

The bar has been raised.

Time is on my side - petrified wood sharpening stone

So, since I've recently been working with Sheetrock, plaster, and tape, my poor little brain has been getting all twitchy because a few days have passed without me sharpening anything.-- *sad*--

I had heard somewhere that you could use petrified wood as a sharpening stone. Hmmmm......

The small piece was a test and.... it actually did something! Go figure. It is no surprise that it would scratch the metal since petrified wood isn't actually wood at all, but more of a wood shaped piece of quartz. The process is called permineralization and the Wikipedia gods will tell you all you need to know about that. I, on the other hand, can tell you how to sharpen a chisel using a fossil. Maybe I can contribute an entry?

Anyway, what surprised me was that the scratch pattern was actually fairly even with a slow, but respectable, rate of metal removal. It even felt like a sharpening stone. Decent feedback, a tendency to"squeak" and grab-the-earth at times, and VERY little slurry production because the stuff is pretty hard. That said, it only took me about 15 minutes to turn this chunk of fossil into a sharpening stone.

I polished the flat grain face to 1200 grit and when I get around to it, I'll stick it onto a piece of stone to anchor it.
While not the fastest stone around, it is definitely a keeper. My wife's grandfather picked it up who knows how long ago, so it has history in more ways than one. And it looks cool!


How did it work?

We'll start with the Frankenstone (3000-5000)

Too hard, needs slurry.

DMT 1200 diamond nagura.

Black swarf ( it's working!)

Not too bad...kinda slow, but pretty smooth, some scratches but shallow.

Not a full mirror, but close. Definitely shiny steel and some superficial shine to the iron/jigane.

Control/reality-check. Ozuku asagi. Faster, smoother, and only the finest of scratches. Perhaps not a fair comparison?

The green mystery inkstone. This feels very similar in use and the scratch pattern is similar. This IS faster, though.

Let's mix it up even more. I'm going to try using the P-wood with the ODC nagura.

Faster metal removal, smoother action and just all-around easier to use. The ODC gives a nice even matte finish to the jigane. I like that.

Still WAY better. Ozuku asagi w/ODC. Faster, smoother, easier. Nice definition. 

Well, you can't have too many sharpening stones. This was just sitting in a shoebox and, surprise surprise, it works like your average super-hard Japanese natural waterstone. Not the greatest, but definitely interesting. I looked at some other pieces of petrified wood at a store in town, most of which looked like rocks. Agate or something. This piece is probably an example of incomplete metamorphosis and still looks a fair bit like wood. A conifer of some sort.

When I first got interested in natural sharpening stones, I thought that they were very rare and special (well, the best ones ARE!) but it turns out that the darn things are everywhere. The trick is to first learn how to use natural stones and having a "real" sharpening stone will help. That way, if you are having problems, you will know that the fault lies with your technique. The stone is a known quantity. The second thing would be that a nice stone makes sharpening fun ( well, some of us are easily entertained....), but a bad one will keep you from ever learning anything because you won't use the darn thing. Then you're back to the whole dull tool situation. Also, as you get better, your preferences and priorities will change, so don't sell the farm just to buy into some system. Ebay is full of "systems" that someone else outgrew. At the least, buy used and let someone else pay the depreciation.

I wish that I had learned some of this stuff sooner.

Toishi envy....

The pile of kanna parts and pieces was really getting in the way, time to finish up some more tool rehab and rehabilitation...

Wow! Seeing these in a pile makes me think.... I don't know what it makes me think.... I DO need to make a tool rack, that's for sure! The tool R&R was mostly just blade repair, dai adjustment and fitting, correcting warpage. The usual round of tasks that are required for most of my Ebay purchases. These were all beaters.....clean and functional now.

Speaking of Ebay....I have heard that most of the Japanese tools are overpriced, non-functional items that no one in Japan wants. The good stuff stays in country and is bought and sold elsewhere, cause it ain't on "the bay". Where is it? The good stuff?

It's at Yahoo auctions, Japan. I am SO envious! REALLY good stuff (like I've NEVER seen on Ebay!) and about 1/3 the U.S. prices..... It looks like most sellers won't ship international.....*sigh*... speaking of envy...



Tanaka Kiyoto, my Toishi hero, has been trying out some newly mined stones.

From the blog "Perspective of guitar production house", craftsman Tanaka Kiyoto.

Nao natural whetstone is operated by a really great sounding guy who is bringing some REALLY nice stones to public attention. He is digging them from the parent stone, cutting them to size, testing (using some very impressive kanna blades!) the performance on a variety of tools, and writing about his findings. Reading his blog and follower comments makes me realize how little I know about Toishi and how they are properly used. It IS good to know that other people have the same affliction, of wanting to sharpen things just for the pleasure of sharpening. I need to learn if there is an actual word or phase for this.... maybe there is a support group?

What Nao natural whetstone has is native rock...... nice stuff. What I've got..... Remember the picture at the top? The white thing in the background... that was either a doorstop or a piece of rubble from the old stairway to our house, I can't remember which. I tripped over it for about the 100th time, then thought "What the heck....".

Crunchy quartz

Smooth quartz

"Use what ya brung". I know. Too hard. Doesn't release grit. Too scratchy.... Yep, all of the above. I'm starting to feel as though my day isn't complete without firing up the diamond wheel grinder. I cut and smoothed 2 sides to 1200 grit, just to see if there was any difference in the grain orientation. If that was, it was not too significant.

This was about 30 seconds work, beginning with a diamond nagura slurry. It did something..

Much better. This was 15 second, maybe, using the ODC nagura. 2000 grit or so.

This thing actually worked to a degree. I will use it a bit more to see how much of the abrasive action was due to the surface profile left by the diamond plate and how much was the actual stone itself. It seems to be a somewhat slower mid-range stone, around 2000 grit, but with a very consistent and shallow scratch pattern. The finish is more akin to a sandpaper finish, rather harsh and reflective, but also easily erased by a higher grit stone. The ODC nagura helped the stone produce a nice creamy slurry that cushioned the feel considerably and made for a tolerably smooth feel. I was quite surprised, so much so that I had to double/triple check, then compared the resulting finish to......

My green "Ink" stone. It took about 30 seconds to erase the quartz scratches. Hazy mirror.

Ozuku asagi, 30 seconds more and full mirror on steel.

This was totally for fun, I was expecting NO success at all. What I found was a pretty big surprise. Not world class, by any means, but.... interesting. I tried: straight water (slow, a bit rubbery, some "grabbing the earth/stiction"), diamond nagura (smoother, much faster), ODC #3 (coarse crunchy grit, thicker creamy slurry, fastest), diamond again, water again, ODC#1 (smooth nagura, thinner slurry, better feedback, slurry degraded too fast).

Then: "Ink" stone, Ozuku, quartz w/ODC#1.... Ozuku, quartz W/ODC#3, Ozuku finish.

Back and forth quite a few times, but the scratches are really easy to erase. The stone may have "mellowed" in use, we'll see. Very hard. Rather slow. Might be good for flattening ura's?

Interesting yard rock. Not anything like Nao natural whetstones, though. His Wakasa waterstones make my heart go all a'flutter. Check out his blog to see some of the shavings he pulls.... beautiful smoky mirror finishes, WAY cool ren-tetsu iron kanna blades..... My eyes are green....

Au naturel - Ink stone (not) mystery stone

Another Ebay mystery. I took a gamble and bought this stone from an Asian antiquities seller. He listed it as an ink stone, but without a well to hold ink......hmmm. The pictures showed what looked like tiny spots or holes, like you see with a suita stones, and it also had some prominent streaks of renge (red pattern). Looks like a sharpening stone to me. Luckily, it works like one too.....

Size 150-100-20 mm, olive green, evergreen, red and white. Slightly translucent!

This is the face that I use. All sides are finished, so no skin.

The spot is a low point. I REALLY didn't want to surface this thing down. It's HARD!

Uses basically no water

SUPER hard! This stone is really beautiful, lots of color and looks 3D. When I received it, it was all polished up with wax, I think. It looks like a gemstone, like a low grade jade or marble. Jadeite? Jasper? Funny to think of me sharpening old rusty tools with a semi-precious gemstone, haha. I tried it out, and the tools had a bad tendency to dig in and gouge and it felt very "grabby" or sticky. The tool would skate, then grab and gouge. Ha! Street fighter stone!

I lapped it with great difficulty using a 1200 DMT diamond stone. It forms a milky white, very thin slurry. Once it was flattened, it worked well. Needs a nagura! Expert stone, way above my pay grade. I'm still learning.

Shall we?

DMT 1200 slurry, sometimes gray, other times white.

T= 1 minute ( after jyunsyou). See the reflection in the steel?

Nice bright mirror!

Forms a creamy slurry, dries slowly and gives a crazy deep finish that just improves the longer that you use it. Surprisingly fast considering how hard it is. I have no idea what this stone is, but it acts like something special. From the photos of the 100's of other stones that I have looked at, it looks a bit like an ozuku asagi, but it is pretty well impossible to tell, especially from photos. I can't speak for everyone, but my photos suck. Ozuku is a mine in japan, asagi is just the color green, I think. It doesn't matter, but I am curious. I would buy another, but I am pretty sure that I couldn't afford it. Definitely a razor stone.

I haven't done it yet, but one of these days, I am going to do isolation tests to more accurately gauge the grit of each of my stones, as a reference piece. It is actually completely irrelevant, but when I started buying stones, I pent a lot of time looking for this type of information. I am currently working my way through Tanaka Kiyoto's  blog. He is a Japanese luthier and writes at great length about tools and sharpening stones. Oh yeah, and crafting guitars. He seems like a REALLY cool guy. I also really wish that I could read kanji. As it is, with Google translate I am only getting about 20% of the content and there is a lot to learn, if you know what to look for. I strive to learn enough to ask the right questions.


---Addendum---
Speaking of asking questions, I am still trying to figure out what this stone is. There are some ink stones without wells, I have found.

So there ya' go.