HONING THE MASTRO LIVI WAY

[cugel]

In my reading of the subject its not the single cutting particles that are breaking down, rather the size of the particles containing multiple single cutting units. ie chemical bonds aren't being broken. Its just pieces of "dirt" that contains abrasive. You start with big pieces and those pieces of dirt get smaller.

Best demonstration I have done is to compare a diamond slurry on a jnat (large particles since the DMT plate is 600 grit) vs. a slurry generated from a very hard fine tomonagura (smaller particles). In my hands the DMT slurry cuts way way faster and its unlikely thats due to diamonds in the slurry from the plate since my edges are great. Nobody is claiming the particles that actually cut the steel are getting smaller, or they shouldn't.

I think of it as a popcorn ball (remember those disgusting things) vs. plain old popcorn. The popcorn is the cutting particles and they stay the same. What changes is how they are presented to the steel. Working the slurry breaks down the popcorn ball (held together with binders in the stone, clay etc.) but not the popcorn itself. I realize how silly this sounds but thats my take on it.

 

[Namkcakram]

I genuinely believe the slurry does break down from everything I’ve observed in use with multiple stones honing razors, cutlery, and woodworking tools of various steel compositions tempered anywhere from 58-66ish Rockwell. I actually notice the slurry breakdown effect much less with tools, because the pressure used combined with the fat laminated iron bevels and generally softer stones seems to make auto slurry everytime. Woodworkers don’t generally view slurry in much the same way we do. You just kinda flatten the stone by diamond plate and then hone on whatever is still floating on the surface. The tool will generally kick up more slurry than is there currently anyways. Nobody really finishes tool edges on ultra hard awasedo, a finisher they’d put on a high pedestal might be a medium hard very fine suita or something.

I’m not a believer that there is magic, but varying pressure does not explain the “breaking down” phenomenon. I know my stones and I can experiment for myself with varying pressure and see that there is a correlation between pressure used and bevel results, but there is a SEPARATE correlation between the Amount of time a slurry is used and the effect on the bevel. It is affected by the pressure you use, but the “breaking down” effect is very much an additional, separate, observable, and repeatable phenomenon. Results also vary but are as repeatable as anything else in this hobby from stone to stone. The slurry from a given stone will generally start at a certain scratch pattern time after time, and it will “break down” to a certain level of scratch pattern time after time. If you plotted out the starting and finishing effects of the slurries you’d end up with something resembling a viscosity chart of different oil weights across a temperature range. This slurry starts *here and over the course of ~20 minutes it peaks out *there. The results for me would be repeatable between stones, and that’s the part where experience and knowing your stone comes into play. If a blade is tempered hard, slurry X might break down too fast for the bevel polish to keep up, but slurry Y stays coarse for quite a while and might be a better starting point. You might run Y all the way down and then start again with X and the starting point for X is a step backwards in finish quality, but 20 minutes in the results are noticeably better than if you had ended on Y or tried to skip Y and go straight to X. Those are observable repeatable results that you can’t explain away with “you’re using better technique”.

Now what causes that to happen? I don’t have that answer and it seems nobody does, but trying to explain it away with incomplete data is nearly as irrational as saying it’s some type of magic. I’m a chemical engineer so it REALLY irritates me that I don’t have the means to test and measure and prove anything here. All I can say is it’s not a pressure reduction thing, there’s definitely something more complex happening there from what I have been able to observe. I like to think I’m a pretty rational person, but I’ll believe this one just on my own testing even if i have no evidence to write a peer reviewed publication about the subject.

 

[buca3152]

Let's say the slurry changes instead of breaking. It leaves finer stria under mag after you work it. So something is happening.

 

[stone and strop]

In my reading of the subject its not the single cutting particles that are breaking down, rather the size of the particles containing multiple single cutting units. ie chemical bonds aren't being broken. Its just pieces of "dirt" that contains abrasive. You start with big pieces and those pieces of dirt get smaller.

Best demonstration I have done is to compare a diamond slurry on a jnat (large particles since the DMT plate is 600 grit) vs. a slurry generated from a very hard fine tomonagura (smaller particles). In my hands the DMT slurry cuts way way faster and its unlikely thats due to diamonds in the slurry from the plate since my edges are great. Nobody is claiming the particles that actually cut the steel are getting smaller, or they shouldn't.

I think of it as a popcorn ball (remember those disgusting things) vs. plain old popcorn. The popcorn is the cutting particles and they stay the same. What changes is how they are presented to the steel. Working the slurry breaks down the popcorn ball (held together with binders in the stone, clay etc.) but not the popcorn itself. I realize how silly this sounds but thats my take on it.

I believe this has been proven as well. The binder breaks down, the actual abrasive particle does not.

 

[Namkcakram]

Let's say the slurry changes instead of breaking. It leaves finer stria under mag after you work it. So something is happening.

One of those things that can’t be explained satisfactorily, but is supported by anecdotal evidence everywhere you look.

 

[buca3152]

Imo it's easier to just use these stones and judge them for their results. The textbook stuff I leave to you guys. Lol.

 

[kohalajohn]

buca3152, when you say the microscope shows finer stria after working it, that does support the idea of breakdown.

But that could also be due to the person using progressively lighter pressure. Maybe it's both.

The fact that the jnat folk use a progression of stone and nagura, suggests there is no breakdown. If breakdown occurred, there would be no need for a progression.

But then on the other other hand, Doc226 no longer uses naguras. He just rubs an atoma 1200 on a jnat and goes all the way on that one slurry.

So does that mean doc226's slurry is breaking down? It could. But another explanation is that light pressure would cause the razor to lightly glide over the big boulders, and just the tip of the big boulders would caress the steel. So you have fine stria. And maybe a smoother shaving experience, more so than if the fine stria were being created by very small bounders being ground hard, all the way, into the steel.

Big boulders being gently pushed, would create wide shallow valleys. Small bounders being pushed hard, would create the same shallow depth, but narrow valleys instead of wide ones. Maybe the former effect feels better. So if mastering pressure is important, that may explain why the jnat world is seen as more of a skill world. People don't talk glowingly of some honemeister who uses norton synths. But they praise doc226 and his skills on jnats.

I think you could take coarse sandpaper and with a very soft and skilled and gentle touch, create the same effect on wood as if you were using fine sandpaper. Only let the very tops of the heads of the huge boulders touch the wood.

Maybe I'm wrong.

Maybe every theory is correct. The popcorn ball theory is correct, that there's a huge clump of crystals and the clump is coming apart as you hone. I kinda like that one.

And it's also true that we learn to use lighter and lighter pressure as we go, so the particles don't dig in as deep.

Maybe the only reason to use intermediary progression stones is to save time and ensure we don't screw it up. A 4/8 synth will do what it does regardless of our skill set. You don't have to have the "sense" that you're grinding down slurry at the right rate, and the "sense" that you're adjusting your pressure at the right rate.

 

[buca3152]

Here's my typical progression. 1 k chosera to mid-range stone with atoma 1200 slurry. I work that and then spray off the slurry from the mid-range and dump it on my finisher. The razors goes right to polish. Meaning there is a very short process to refine this edge. I'm more interested in the process and result. Not necessarily having to know exactly what is happening only that I am getting the desired result. Not knocking the knowledge seekers. Just saying the analysis of many of these things takes more time than actually doing them.

 

[Namkcakram]

buca3152, when you say the microscope shows finer stria after working it, that does support the idea of breakdown.

But that could also be due to the person using progressively lighter pressure. Maybe it's both.

The fact that the jnat folk use a progression of stone and nagura, suggests there is no breakdown. If breakdown occurred, there would be no need for a progression.

But then on the other other hand, Doc226 no longer uses naguras. He just rubs an atoma 1200 on a jnat and goes all the way on that one slurry.

So does that mean doc226's slurry is breaking down? It could. But another explanation is that light pressure would cause the razor to lightly glide over the big boulders, and just the tip of the big boulders would caress the steel. So you have fine stria. And maybe a smoother shaving experience, more so than if the fine stria were being created by very small bounders being ground hard, all the way, into the steel.

Big boulders being gently pushed, would create wide shallow valleys. Small bounders being pushed hard, would create the same shallow depth, but narrow valleys instead of wide ones. Maybe the former effect feels better. So if mastering pressure is important, that may explain why the jnat world is seen as more of a skill world. People don't talk glowingly of some honemeister who uses norton synths. But they praise doc226 and his skills on jnats.

I think you could take coarse sandpaper and with a very soft and skilled and gentle touch, create the same effect on wood as if you were using fine sandpaper. Only let the very tops of the heads of the huge boulders touch the wood.

Maybe I'm wrong.

Maybe every theory is correct. The popcorn ball theory is correct, that there's a huge clump of crystals and the clump is coming apart as you hone. I kinda like that one.

And it's also true that we learn to use lighter and lighter pressure as we go, so the particles don't dig in as deep.

Maybe the only reason to use intermediary progression stones is to save time and ensure we don't screw it up. A 4/8 synth will do what it does regardless of our skill set. You don't have to have the "sense" that you're grinding down slurry at the right rate, and the "sense" that you're adjusting your pressure at the right rate.

You’re explaining away the part where it goes slurry fresh -> microscope with coarser Stria -> honing a while -> microscope with finer Stria. Yes that’s possibly a pressure thing. But you’re not addressing the whole picture.

What you’re not explaining is fresh slurry from coarser stone/rough stria -> hone for a while -> much finer stria, THEN start with fresh slurry from a finer nagura and the stria are visibly coarser than the end of the previous stage -> hone a while -> stria are mysteriously much finer than end of previous stage.

Pressure would explain it all away if it were a smooth progression, but it isn’t. A good long progression is one step back at the beginning of each stage followed by 2-3 steps forward after the slurry is broken down and honed on for a while. You can re-introduce fresh slurry from the next finer stone and see another step backwards again.

That’s all observable and repeatable while trying your best to control constant pressure and stroke technique.

Believe me I’m a man of science and it bothers me that I don’t have a satisfactory answer because I want to know what’s going on at least as badly as anyone else here, but it absolutely can’t be explained away by something as simple as a pressure variation.

 

[Namkcakram]

The difference is also pretty pronounced when you go side by side with a slurried coticule and a slurried JNAT. The garnets are drastically harder than any forged steel so on coticule slurry you can observe dilution and pressure change, but total lack of any abrasive break down. Then you do the exact same process with a similar density JNAT, and you can see dilution or pressure changes but there’s definitely an extra unexplained X factor present. The JNAT particles are much closer to the hardness of forged steel, especially steel left nearly un-tempered like some Japanese razors. Given that the theory most people go with to explain the X factor is breaking down or some type of burnishing of the abrasive particles. Anyone else can choose not to believe the slurry particles change over time, but you still have to address the X factor that everyone observes and I haven’t seen a more compelling theory yet.

 

[dundak]

So you find that you can go from 3k to finish on a convex ark?
.

You can go from bevel set to any finisher. That’s what I do and have never used a progression.

I’ve heard lots of explanations why but they never compute and I have never seen superior results over the 1 or 2 stone method.



Sent from my iPhone using Tapatalk

 

[buca3152]

A very simplistic method works. So that means that much of what we did is not necessary. I will say that for sure. So I think it's beneficial to say "do this to achieve that". The textbook version however is much longer. Lol.

 

[kohalajohn]

Evidently a lot of european professional blade makers say that we use far too many stones.

I certainly learned that this morning. I went from bevel setter to finisher and it was fine.

And about slurry breaking down. What stoneandstrop says really sounds like the truth to me:

"I believe this has been proven as well. The binder breaks down, the actual abrasive particle does not."

So you start off with a big clump of binder and particles. The clump breaks apart over time. And in addition, you use less pressure as you go along.

 

[cugel]

For someone like me who is not an expert at honing, more stones = more chance for errors!

 

[Namkcakram]

Evidently a lot of european professional blade makers say that we use far too many stones.

I certainly learned that this morning. I went from bevel setter to finisher and it was fine.

And about slurry breaking down. What stoneandstrop says really sounds like the truth to me:

"I believe this has been proven as well. The binder breaks down, the actual abrasive particle does not."

So you start off with a big clump of binder and particles. The clump breaks apart over time. And in addition, you use less pressure as you go along.

You tell yourself whatever you want, but again you’re insisting there’s a change in pressure when I’m telling you constant pressure yields full “break down” effect. It’s not hard to rule out the varying pressure hypothesis. Repeatedly. The clumps hypothesis can explain most of what we observe, and it definitely explains why “diamond nagura” slurry takes forever to get to a real final finishing state but tomo nagura slurry can put you straight into the finishing realm instantly.

 

[alex1921]

I would like to point that the article with the "binder breaks down but the abrasive doesn't" has a lot of limitations. Few random pictures of slurry and this major conclusion is drawn? That wouldn't fly in any scientific magazine so I would take it with a grain of salt.
Something is breaking down, I am not gonna argue what, but something does. You can see it, you can feel it. Specially with thin tomo slurry.
Theoretically and practically there is a limitation to how much whatever breaks down does break down. If I use coarse suita slurry it will not look the same as a nice fine tomo slurry. Both on the same hard stone. The result is gonna be different.
Add to that that a botan will never reach the degree of refinement of a koma but again, with both you can feel the change was you hone.
Conclusion, things are more complicated than they seem, slurries interact with base stone differently etc.
I think that's the reason why you can use different Jnats and get a decent result but occasionally find a superstone that just blows your mind.

 

[Chan Eil Whiskers]

 

[Namkcakram]

I would like to point that the article with the "binder breaks down but the abrasive doesn't" has a lot of limitations. Few random pictures of slurry and this major conclusion is drawn? That wouldn't fly in any scientific magazine so I would take it with a grain of salt.
Something is breaking down, I am not gonna argue what, but something does. You can see it, you can feel it. Specially with thin tomo slurry.
Theoretically and practically there is a limitation to how much whatever breaks down does break down. If I use coarse suita slurry it will not look the same as a nice fine tomo slurry. Both on the same hard stone. The result is gonna be different.
Add to that that a botan will never reach the degree of refinement of a koma but again, with both you can feel the change was you hone.
Conclusion, things are more complicated than they seem, slurries interact with base stone differently etc.
I think that's the reason why you can use different Jnats and get a decent result but occasionally find a superstone that just blows your mind.

Agreed completely on the most commonly referenced articles about this... not up to any standard of “proof” , but definitely far better than what I’m equipped to do and measure right now.

The big thing that jumps out at me looking through are 1: if everything breaks down and silicates remain unchanged, the stria should actually get deeper as you hone longer. And 2: the photos didnt seem able to capture what could be a burnishing or smoothing of the cutting edges on irregularly shaped silicates. Rounding off a few cutting edges that are only angstroms wide could drastically change the cutting effect on the bevel. That would basically explain everything that’s observable from the finer and finer stria to the particles seeming to remain almost constant size.

 

[SliceOfLife]

Agreed completely on the most commonly referenced articles about this... not up to any standard of “proof” , but definitely far better than what I’m equipped to do and measure right now.

The big thing that jumps out at me looking through are 1: if everything breaks down and silicates remain unchanged, the stria should actually get deeper as you hone longer. And 2: the photos didnt seem able to capture what could be a burnishing or smoothing of the cutting edges on irregularly shaped silicates. Rounding off a few cutting edges that are only angstroms wide could drastically change the cutting effect on the bevel. That would basically explain everything that’s observable from the finer and finer stria to the particles seeming to remain almost constant size.

Silica particles do fracture and round off. Like I mentioned, anyone who uses sandpaper knows this... and there's a lot less silica on silica interaction there vs slurry honing on a stone. I believe high end papers actually rate their particles based on how much use before they are appreciably worn down. Jnat users popularly suggest taking advantage of this fact in a way that most stones don't. Like I mentioned, I think that's mostly based on honing larger tools for VERY long periods of time (ask a sword sharpener why they charge several hundred dollars to sharpen a sword and the answer will be the time involved being hours, even days of labor).

I think based on that heavy use (Hours under several lbs of pressure) of slurry, people have translated that down to fifteen minutes under less than an ounce of force under a razor creating the same effect... which I don't see being reasonable. And the sellers of low end stones on places like eBay absolutely LOVE this theory... go look at all the listings about how you can't consider the jnat refinement based on what the stone actually does because it's only limited by YOUR skill because "magical slurry".

And if the practicality of breaking down silica with minimal time and force is called into question, the friability of the matrix medium is a quick and easy backup argument... but I suspect the truth is probably that you're just seeing the effect of more time on an extremely fine abrasive in a very low force honing technique. If you're looking for slurry breakdown and you get additional refinement with more time spent... you're going to find slurry breakdown, whether or not that is actually the reason.

 

[Namkcakram]

Silica particles do fracture and round off. Like I mentioned, anyone who uses sandpaper knows this... and there's a lot less silica on silica interaction there vs slurry honing on a stone. I believe high end papers actually rate their particles based on how much use before they are appreciably worn down. Jnat users popularly suggest taking advantage of this fact in a way that most stones don't. Like I mentioned, I think that's mostly based on honing larger tools for VERY long periods of time (ask a sword sharpener why they charge several hundred dollars to sharpen a sword and the answer will be the time involved being hours, even days of labor).

I think based on that heavy use (Hours under several lbs of pressure) of slurry, people have translated that down to fifteen minutes under less than an ounce of force under a razor creating the same effect... which I don't see being reasonable. And the sellers of low end stones on places like eBay absolutely LOVE this theory... go look at all the listings about how you can't consider the jnat refinement based on what the stone actually does because it's only limited by YOUR skill because "magical slurry".

And if the practicality of breaking down silica with minimal time and force is called into question, the friability of the matrix medium is a quick and easy backup argument... but I suspect the truth is probably that you're just seeing the effect of more time on an extremely fine abrasive in a very low force honing technique. If you're looking for slurry breakdown and you get additional refinement with more time spent... you're going to find slurry breakdown, whether or not that is actually the reason.

It’s PSI exerted on the hone that matters, not actual force. An elephant can stand on most hardwoods without any effect at all, but an 85lb super model in high heels will leave visible pebble shaped indentions every heel strike.

Japanese tools are intentionally designed with wide (enormous by our standards!) bevel surfaces to facilitate honing at a perfectly consistent angle for those extended periods. The force exerted and the soft wrought iron/low carbon steel portions of the bevels contribute to much more auto-slurry. Those factors combined with the honing techniques most commonly used for a sword, kanna blade, chisel blade, kitchen knives... really nobody honing other objects is staying on one batch of slurry for any extended length of time. The “more pressure for hours” argument really doesn’t hold up if you’re familiar with honing other Japanese tools on JNATs. We’re the only weirdos trying this hard to go a full honing session on one batch of slurry with no auto slurry. We also have the lightest tool weight by maybe a factor of 10 (against kanna blades or chisels), but we have the smallest bevel contact surface area by at least a factor of 25 (to those same tools) or even a factor of multiple hundreds if you have a flat stone and smiling razor. Surface area and weight are both single order factors in the compressive pressure on the slurry so we must be at least in the ballpark of a fat katana bevel on a huge stone with 1/4 a polisher’s body weight bearing down.