If you guys are really curious, the abrasive particles in Jnats are actually quite a bit finer than you'd suspect from their initial grit due to the stones containing macro-structures made up of particles bound together. These structures break down during use into the individual particle size. This happens much more on the surface of the stone, the act of slurrying being mostly sufficient to fully disassociate these structures in the free slurry. However, with certain techniques matched with certain stones, free slurry is more efficient at refining the structures embedded in the stones surface than a tool on water is, creating a sense of the slurry actually refining with use. And I know this because potato.
Is japanese natural awasedo grit really friable?
- Thread starter alx gilmore
- Start date
Do you have a pic of the potato?
Sorry, I made hash this morning.
Im with you brother! If I want to learn to drive, I dont need to know every facet of how a car works. And these discussions have been had for a long time. Nothing good comes out of them IMO. If anything they impede or intimidate some readers from taking the first step. The lapping film guys are right about us. Too much ado about nothing. Rub steel on stone with various small rocks, work them, shave test repeat until you find the results you like. Hone and shave, hone and shave is the only way til you are satisfied with what you have.Thank you for stating this. As a person new to honing on JNATS, sometimes not knowing is bliss for me. Case in point, I started out using a microscope all the time on my edges. Now, I use a loupe more often and my senses of hearing, eyesight and feel while the blade is on the stone to tell me what is happening. Do I believe that my slurry breaks down? Yes. Can I prove it to anyone else here or another "un named forum full of condescending experts"? No. Do I care? No.
Why?: Because no one else shaves with my edges for money. And, of the very few who have shaved with an edge that I honed for free or for a nominal fee, I got no complaints either because they were a. satisfied or b. They were being too nice to me.
I for one don't like to see these conversations degrade into nonsense. It's certainly good for the newbies like me to read these conversations and learn but, I find it disheartening to read some of the quips and barbs being exchanged between people whom I have had respect for. If I want that, I can go to another forum to get berated, chastised and made to feel inferior.
We don't have that here thank goodness. And sometimes, even the most experienced honers get too involved in minutia and lose track of the goal, the smoothest sharpest edges.
Besides, everyone knows that it's really all about Unicorn farts that smell like Skittles anyway.
Frank
I don't know, I kinda like these discussions. If everyone agreed on everything there wouldn't be a need for a forum, just a webpage with facts would do.
Hearing other people's theories on how a stone works, or seeing actual pictures of slurry is actually pretty cool. I can't have enough of those SEM pictures! Granted it probably won't help much when honing though.
Hearing other people's theories on how a stone works, or seeing actual pictures of slurry is actually pretty cool. I can't have enough of those SEM pictures! Granted it probably won't help much when honing though.
You win the internet.
I can't tell you how many times someone took offense to being disputed, questioned, or debated on a forum and I physically face-palmed at the reasoning it takes to feel that a medium specifically made for these things is not the place for them.
I'm a little disheartened when folks so strongly suggest that delving into the minutia of why, is somehow wrong headed and fruitless. By understanding why JNats operate the way they do it enables me to take empirical data from experience with hones I know and combine that with theory and opinion from folks I have found to be knowledgable on the subject. I then make decisions on tools and techniques and add that result to my knowledge base. I am continually amazed at the intellect and willingness to share of many on this forum.
Theres nothing wrong with knowledge seeking if there can be a way to prove or disprove something. The conclusions in threads like this are inconclusive ALWAYS. Like the chicken or the egg. Everyone agrees it works. BUT it is not the first or last, its been a while since a tape or dont tape thread has been up. LOL
You are correct about measuring size distributions, particularly if you are trying to use sizing/counting software. However, I think that in this case the largest particles will dominate the "effective" grit, even if they are only 1/1000 of the particles (by count). And yes, there are several alternative explanations.
I assume you are familiar with Mica - the Phylosilcate particles (silicate not silica) will cleave into thin, flexible, soft, sheets just like Mica does on a macroscale. This is the "binder" component.
The Silica (abrasive) may be in the form of a "superparticle" if it is a copuscular agglomerate, like an opal. It seems to me that these particles would have to be bonded strongly enough to act as a large grit particle (and released from the stone as one) but weakly bonded enough to break into individual particles with the typical amount of time/force used in honing.
IMO, there is a general principle in knowledge expansion:
observation ---> explanation/model/theory ---> extrapolation/prediction ---> testing the prediction & new observations ---> improved explanation and understanding
If someone doesn't have experience with hard and fast stones and using nagura it might seem like nothing is happening. I find with softer stones that release slurry automatically its a lot harder to observe a breakdown. Now with nagura on a hard base stone it's pretty easy to see this.
Try taking a knife with a wide bevel and finish it on a hard stone with water only. Then raise a slurry. Inspect after a few strokes and witness the cutting force of the slurry as well as the finish it imparts. Continue working slurry and observing. I believe it's easy to see that the finish improves as slurry is worked.
It's a lot harder to see this effect on a razors bevel and especially with some if the well ground razors that appear to have bevels the width if a human hair.
Try taking a knife with a wide bevel and finish it on a hard stone with water only. Then raise a slurry. Inspect after a few strokes and witness the cutting force of the slurry as well as the finish it imparts. Continue working slurry and observing. I believe it's easy to see that the finish improves as slurry is worked.
It's a lot harder to see this effect on a razors bevel and especially with some if the well ground razors that appear to have bevels the width if a human hair.
We know, from a scientific standpoint, that the silica particles in Silaceous Shale stone can be friable.
It's a fact - but 'can be' and 'will be' are two different things.
We also know that we hone on slurry, and the edges we are creating, with continued effort, are refining progressively.
So it's not too hard of a jump to see where this is going - but it is an assumption.
Maybe - the slurry breaking down isn't what is happening. But it seems like that is what's happening. I'm good with that.
I'm not too particularly concerned about any possible issues resulting from a mistaken belief here.
I do know that when I hone a razor on a Jnat it gets sharp. So - it seems like the reason to use them panned out pretty well.
I didn't choose to get into, or continue to use, Jnats because the slurry breaks down. It really doesn't matter if it does or it does not. Really - it doesn't. I think it does - to what extent? Dunno - but it really doesn't matter.
Because - I mean - you know - Potato.
It's a fact - but 'can be' and 'will be' are two different things.
We also know that we hone on slurry, and the edges we are creating, with continued effort, are refining progressively.
So it's not too hard of a jump to see where this is going - but it is an assumption.
Maybe - the slurry breaking down isn't what is happening. But it seems like that is what's happening. I'm good with that.
I'm not too particularly concerned about any possible issues resulting from a mistaken belief here.
I do know that when I hone a razor on a Jnat it gets sharp. So - it seems like the reason to use them panned out pretty well.
I didn't choose to get into, or continue to use, Jnats because the slurry breaks down. It really doesn't matter if it does or it does not. Really - it doesn't. I think it does - to what extent? Dunno - but it really doesn't matter.
Because - I mean - you know - Potato.
The abrasive particles on sandpaper break down. Anyone who has used sandpaper knows this. Sandpaper doesn't dull JUST because particles are lost. The ones that are there lose their edge. Likewise with Diamond plates. EVENTUALLY. Everything breaks down. Do Abrasive particles on Jnats break down at a rate where the avg effective cutting grit of the slurry is reduced significantly during the honing of a single tool? No, that's absurd. Of course, the cutting action could be comprised of multiple particles acting upon (or bound to) one another, as heavy coticule slurry is, and as such COULD refine and break down under use relatively quickly as what could be expected from the crystalline structures which perform the cutting action. But that doesn't sound as SPOOKY AND MYSTICAL as individual particle breakdown. Is there any functional difference? Not much. Is it an important qualification for people who like things ordered and reasonable? Maybe. Potato? Absolutely.
Them's fighten words.
Originally Posted by SliceOfLife
....... Do Abrasive particles on Jnats break down at a rate where the avg effective cutting grit of the slurry is reduced significantly during the honing of a single tool? No, that's absurd......
Them's fighten words.
Yeah, not really sure I agree with that. Try it on something wider than a razor bevel and see what you come up with.
I've been spending, unfortunately, long stretches of time these last few days in a hospital waiting room. Putting some of that time to good use, I've looked on the interwebs for any real information (i.e. something published in a reviewed journal or a book vetted by research institutions) in English on the makeup of Jnats. I've yet to find anything definitive, but that's also because of vast swaths of ignorance on my part that may have caused me to overlook something.
What puzzles me is why we keep referring to binders and abrasives. Nothing I've seen so far suggests that Jnats are comprised of components that can be so easily categorized as a binder and an abrasive. What's more, it's not clear that there aren't multiple types of components. Those parts of the stone which we blithely refer to as binders could easily be relatively soft (2-2.5 MOHs is what I've seen) or they could be quite hard (as high as 7 which is on par with an Arkie). As for the abrasive particles, if such a distinction really does exist, I couldn't find anything-yet- which definitively states that such a distinction exists; those particles may also be of various sizes and hardness and shape.
Another thing that surprised me is that the understanding I had of Jnats was that they were all sedimentary rocks That's not as obvious as I thought it was. It seems that many of them my be igneous or metamorphic or a combination of the three. For instance, rocks originally formed as sedimentary can easily go through a metamorphic stage. Those soft "binders" change into something quite different. Were the miners only harvesting sedimentary rocks? How could they tell?
I guess all this is to say that for those of us who can't speak or read Japanese, there's precious little research focusing on these stones that can give definitive answers...or, it says that I just haven't found it yet or am too stupid to understand what I have read. Kyoto Univ appears to have an excellent geology department, but the professors obstinately publish in their native language. How unfriendly.
I'm going to keep looking because this is fascinating.
What puzzles me is why we keep referring to binders and abrasives. Nothing I've seen so far suggests that Jnats are comprised of components that can be so easily categorized as a binder and an abrasive. What's more, it's not clear that there aren't multiple types of components. Those parts of the stone which we blithely refer to as binders could easily be relatively soft (2-2.5 MOHs is what I've seen) or they could be quite hard (as high as 7 which is on par with an Arkie). As for the abrasive particles, if such a distinction really does exist, I couldn't find anything-yet- which definitively states that such a distinction exists; those particles may also be of various sizes and hardness and shape.
Another thing that surprised me is that the understanding I had of Jnats was that they were all sedimentary rocks That's not as obvious as I thought it was. It seems that many of them my be igneous or metamorphic or a combination of the three. For instance, rocks originally formed as sedimentary can easily go through a metamorphic stage. Those soft "binders" change into something quite different. Were the miners only harvesting sedimentary rocks? How could they tell?
I guess all this is to say that for those of us who can't speak or read Japanese, there's precious little research focusing on these stones that can give definitive answers...or, it says that I just haven't found it yet or am too stupid to understand what I have read. Kyoto Univ appears to have an excellent geology department, but the professors obstinately publish in their native language. How unfriendly.
I'm going to keep looking because this is fascinating.
Even if you find data written in Japanese, good luck getting it translated correctly.
My understanding.
There are igneous, sedimentary, and metamorphic Jnats.
The stones we refer to as Awasedo are predominantly shale; they started out sedimentary, and have gone through some of the metamorphic stage that would, eventually, lead to further transformation, i.e. slate.
My understanding.
There are igneous, sedimentary, and metamorphic Jnats.
The stones we refer to as Awasedo are predominantly shale; they started out sedimentary, and have gone through some of the metamorphic stage that would, eventually, lead to further transformation, i.e. slate.
I am new to honing and some of this topic is still a bit over my head. It's unfortunate to see some of the responses posted above. I don't know enough or have enough experience to comment on what I think is happening with slurry particles. I greatly appreciate the information given by OP and the respectful arguments for and against the initial hypothesis.
Some of the comments above are disrespectful and, I feel, are out of line. If the topic is something that has been discussed before and has not been agreed upon doesn't mean it's something that someone else can't try to experiment with or try to figure out. If you have a problem with the thread then don't post in it. I have no argument with those who made arguments or respectful comments against the suggestions by OP. I have an issue with those who chose to make jokes about something because they disagreed with the suggestions made or with the post in general.
Some of the comments made above make someone like me second guess whether I should post questions or ask about different topics as I learn to hone.
Some of the comments above are disrespectful and, I feel, are out of line. If the topic is something that has been discussed before and has not been agreed upon doesn't mean it's something that someone else can't try to experiment with or try to figure out. If you have a problem with the thread then don't post in it. I have no argument with those who made arguments or respectful comments against the suggestions by OP. I have an issue with those who chose to make jokes about something because they disagreed with the suggestions made or with the post in general.
Some of the comments made above make someone like me second guess whether I should post questions or ask about different topics as I learn to hone.
Dunno,
I can tell you that I have set bevels/honed out chips and honed to shave ready on single tomo generated slurries.
How I get from point A to point B is not really that important, what is important is I got to point B
To remove small chips with tomo slurry I started with thickish slurry and honed on it, I saw the swarf build up and the chip disappear. I diluted and the edge got sharper.
Did the fineness come from diluting slurry or breakdown of particle? Dunno.
I use a lot of stuff in my everyday life that I have no idea how it works-I am cool with that.
Like Seraphim says I am a caveman-I rub steel on rock, steel get sharp, I shave.
I can tell you that I have set bevels/honed out chips and honed to shave ready on single tomo generated slurries.
How I get from point A to point B is not really that important, what is important is I got to point B
To remove small chips with tomo slurry I started with thickish slurry and honed on it, I saw the swarf build up and the chip disappear. I diluted and the edge got sharper.
Did the fineness come from diluting slurry or breakdown of particle? Dunno.
I use a lot of stuff in my everyday life that I have no idea how it works-I am cool with that.
Like Seraphim says I am a caveman-I rub steel on rock, steel get sharp, I shave.
LEarning to hone is achieved thru practical suggestions and lots of practice. Not scientific lectures. An illiterate person can learn to hone easily by being shown what is important to do, and what not to do. End of story. Thats my take on it. Its a simple thing to do and the practice is what will get you there. Your own observations and shave tests will tell you whats good or great or bad. The rest is academic. Academics is worthless when you are pondering something that cant be proven one way or the other. Has anyone proven if adding tape to the spine will increase or decrease friablity? How bout left handed and right handed honers, those who use 2 hands, bench honers vs hand honers? There has to be one accepted method that is superior! LOL. No there is not. As all of these variants can produce fine shaving edges. And these threads all end up with some very learned honers saying"I wouldnt say yes, but I couldnt say no".
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