Other than the color it's hard to tell them apart.
JNat edge?
- Thread starter Seraphim
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- #22
FWIW - the 'cutters' in the Jnats are by-and-large ~micaceous clay minerals which are platy in nature. The Al2O3 is corundum and is much more equidimensional in nature. A 0.3u corundum particle will cut like a 3u particle while the micaceous particle from the Jnat will have an effective thickness much smaller than the 'ab' dimension and will tend to cut less as the particles 'slide past each other' in slurry. Also looks like there are far fewer corundum grains in the film than there are micaceous particles in the Jnat. Be interesting to see what the scratch pattern looks like from each of these same materials.
Just waxing poetic...
Just waxing poetic...
It's my understanding that the efficaciousness of any given abrasive particle, or rather the difference in efficaciousness between two 'like' abrasive particles is not related to the simple difference between their respective diameters; instead, the difference between the cubes of their diameters seems to be some sort of quasi-logrithmic calculation used to determine the percentage of higher or lower cutting ability one particle will have when compared to another. Ratio is ratio - but since the reasoning behind using the cubed diameter is also directly related to quantity of particulate possible in the slurry, and how a larger surface responds to abrasion differently than a smaller one - one might also factor in mass as an addional variable also, but that's another journey down a long road.
As noted, particle shape, and lets not forget friability, also factor in at a base-line level - I don't know that simply comparing the diameters (or cubes therof) of particle x against particle y can be used to postulate a possible outcome.
For example - .5 micron Crox cuts a whole lot differently than .5 micron mono diamond.
I'm not saying you cant reproduce a visual/physical effect of the honing results from a Jnat with films.. I just think the math is skewed and it's probably not taking anyone in the right direction.
I believe that Seraphim is onto a solution, or a close-enough approximation - but I feel that the solution to the puzzle might be less mathamatical, and more ingenuity-based.
Therefore - I believe he will succeed. I could be totally wrong and he still might succeed... but I just felt like typing a little bit here and since I guess I'm done I suppose I'll just step back and wait for the next photos.
I probably wont ever use films, they seem too clinical. But - I am enjoying the puzzle.
As noted, particle shape, and lets not forget friability, also factor in at a base-line level - I don't know that simply comparing the diameters (or cubes therof) of particle x against particle y can be used to postulate a possible outcome.
For example - .5 micron Crox cuts a whole lot differently than .5 micron mono diamond.
I'm not saying you cant reproduce a visual/physical effect of the honing results from a Jnat with films.. I just think the math is skewed and it's probably not taking anyone in the right direction.
I believe that Seraphim is onto a solution, or a close-enough approximation - but I feel that the solution to the puzzle might be less mathamatical, and more ingenuity-based.
Therefore - I believe he will succeed. I could be totally wrong and he still might succeed... but I just felt like typing a little bit here and since I guess I'm done I suppose I'll just step back and wait for the next photos.
I probably wont ever use films, they seem too clinical. But - I am enjoying the puzzle.
I was thinking that if people can raise a slurry on a Jnat with a diamond card, then the slurry raised by the nagura on a film should approximate that similarly. In thinking deeper, I wonder if the films are too abrasive despite their small micron size? IOW when on a tomonagura slurry its the slurry doing the cutting, not the main stone. So maybe he needs to go to a finer film, or one that has worn down to where it barely abrades, allowing the nagura slurry to do its work? In theory his first attempts should have been successful as that 3 micron film has to finer than a Jnat, no?
I think the main stone plays a part in the slurry breakdown, and I believe it also releases new particles at the same time - so the Awasedo must be factored into the equation. Those particles, I believe, do not all break down identically so there's another variable.
In my own non-clinical testing, there is a difference in honing on slurry generated by a diamond Nagura, as opposed to slurry released via Tomo Nagura.
I'm not certain about how many people have a Tomo that's cut from the Awasedo they hone on. I do, I cut if off myself, and the finish from the slurry it generates is different then one from another 'Tomo' nagura.
3 um is, according to one chart - about 4k JIS. 1 um would be around 10k. I remember reading somewhere that the abrasive particles in nagura are around 1-1.5k in diameter.
Ok - now I'm really going back into the bleachers to watch. d
In my own non-clinical testing, there is a difference in honing on slurry generated by a diamond Nagura, as opposed to slurry released via Tomo Nagura.
I'm not certain about how many people have a Tomo that's cut from the Awasedo they hone on. I do, I cut if off myself, and the finish from the slurry it generates is different then one from another 'Tomo' nagura.
3 um is, according to one chart - about 4k JIS. 1 um would be around 10k. I remember reading somewhere that the abrasive particles in nagura are around 1-1.5k in diameter.
Ok - now I'm really going back into the bleachers to watch. d
Ah, 3mic is too large then. I would think since my jnat actually has a mirror finish at extreme viewing angles it's pretty high grit.
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- #28
My estimates are based on what I'm seeing in the resulting edge and scratch patterns.
I used the nagura with 0.5um film, and the resulting edge is still most strongly affected by the slurry particles (I have to see if I captured an image).
My personal, and very limited experience is that a JNat simply does not finish to as high a refinement level as is possible with uber films/pastes. I gave that JNat edge a shave, and it felt pretty similar to an edge I would get off the 3um film itself, a bit better than that, again, if I were estimating I'd say the finish level of this JNat edge would be a straight up 2um finish.
I'm on my iPhone at the moment, I'll try and post more data later.
I used the nagura with 0.5um film, and the resulting edge is still most strongly affected by the slurry particles (I have to see if I captured an image).
My personal, and very limited experience is that a JNat simply does not finish to as high a refinement level as is possible with uber films/pastes. I gave that JNat edge a shave, and it felt pretty similar to an edge I would get off the 3um film itself, a bit better than that, again, if I were estimating I'd say the finish level of this JNat edge would be a straight up 2um finish.
I'm on my iPhone at the moment, I'll try and post more data later.
My guess is that you might want to try more Jnats.
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- #30
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- #31
+1,
how much release from the base you going to get depends on how hard it is. that is the reason one does not want too soft a stone for ebase since there is lot of released new slurry that does not break down completely before new slurry is released. There are some stones that are so hard they will mess up the edge if not used carefully those do not release any slurry when used.
I think someone might do a better job than I can on a Jnat.
What is interesting to me is you prefer more refinement on finer grit, while I kinda like it the way it is. This is despite my love of CBN. Or are you reverse psychology-ing me?
What is interesting to me is you prefer more refinement on finer grit, while I kinda like it the way it is. This is despite my love of CBN. Or are you reverse psychology-ing me?
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- #34
I think someone might do a better job than I can on a Jnat.
What is interesting to me is you prefer more refinement on finer grit, while I kinda like it the way it is. This is despite my love of CBN. Or are you reverse psychology-ing me?
It depends on how that higher grit is applied.
When finished on an unyielding surface (i.e.- super high grit lapping film directly on a plate, of pastes applied to a firm backing such as balsa or benchstrop) it seems to over-refine the edge, leading to an unsupportable structure and immediate edge degradation and discomfort during the shave (often theoretically attributed to the sharpness of diamonds creating a "toothy" edge, but I have a differing opinion).
Here is an example I've used before--
Before the shave (razor finished to 0.1um diamond film, this shot was taken a couple of years ago, the micrscope lighting setup was different):
After the shave:
When finished on a reasonably high grit (1um-0.5um), with a yielding substrate (either wet paper beneath the film, or paste applied to a hanging cotton belt), this seems to modify both the cutting attributes of the grit, as well as the geometry of the resulting edge.
Here is the same GD that the original Jnat honing was done on. I rehoned it to remove at least one variable, that being the razor itself. Finished on lapping film to 1um, then a few swipes on the chromox belt.
Before the shave:
After today's shave:
You can see that there was little to no degradation of the edge.
With all that hot air out of the way, then I will also add that lately I have been preferring the feel of the edge finished on either Dovo red or 1um diamond on a cotton belt. The chromox edge tends to cut a bit too close for my comfort, and I'm still feeling a bit "tight" after today's shave. The Dovo Red seems to retain most of the keenness, but backs off from harshing out my skin post-shave.
Here's the Dovo Red edge (I just stropped up that same edge above), which looks like this:
Supposedly, Dovo red is like an 8k finish according to their website/info I could find. That certainly doesn't look 8k to me!
Another finish, this time the 1um diamond (just stropped this up too)
So, yeah, I'd be interested in trying out some other Jnat edges. I'm interested in finding out as empirically as I can what seems to make so many people enjoy the shave they get from them.
I have zero experience using a slurry stone (as shown by my use of the wrong edge of the thing!), so perhaps my Jnat honing skills are to blame for me results. Also the lack of a suitable Jnat hone upon which to use the slurry stone has also limited my findings here.
Thanks, Kent for the loan of the razor and nagura for this study. I'll send them back to you not much the worse for wear...
You are welcome. I look forward to trying your edge. Maybe we can try it again next year when my technique improves...
I think, for me, some of what I like about Jnat edges translates out as what Maniaman calls his 'Zen Experience'. It's an emotional thing, not unlike being hypnotized; i.e - you can't be hypnotized if you don't believe you can be hypnotized. So - I believe in my Awasedo and therefore I can hone very well on it.
Not that a Jnat edge isn't its own thing, but its more like the zen thing plus the Je ne c'est quoi the edge has.
Think about it - the edge has to split a hair effectively and efficiently.. it has to do it close to the skin, and it has to not abrade the skin past a certain point. That's just about the whole enchilada.
Ok, so - like, how sharp does it really need to be to do that? There has to be a limiting factor of how sharp is sharp enough to cut the whisker cleanly. The action of refining the edge by dimensions expressed in sub-micron units of measure has to be governend by the laws of diminishing returns. They must also, simultaneously, be governed by un-chartable variables such as the steel's ability to hold the edge and whiskers resistance to being cut.
Realistically, there can't be much of an 'improvement' in an edge past a certain point. I really do believe that a lot of the 'mystique' in these stones stems from the owner's sense that they feel more attached or connected to it for some reason. As a result, the owner hones better because of this. Yes, I do believe that Jnat slurry can be much finer than Coticule slurry or perhaps anything else out there. How much finer, I don't know - but I don't believe that the abrasive particles from any natural stone is going to surpass the 30k mark (and still cut) when honing a razor. Maybe I'm mistaken, but I'm hard pressed to digest the concept of abrasive particles breaking down one complete order of magnitude and still working at a perceptible level. But - again - perhaps I'm wrong and that is exactly what happens. I've decided to keep an open mind about such matters, and that's why this experiment is so interesting to me.
Still - Jnats are, technically, no easier or harder to hone on than Coticules, synths, pastes, or whatever. All those other honing options seem to be able to offer edges sharp 'enough' and in some cases 'too' sharp for one's skill level.
Still - I think my personality 'clicks' with Jnats better. I also click with Coticules, Eschers, and synths - but not the same way. That's the emotional thing... it's like that perfect pair of sneakers that you could always jump higher or run faster in because they fit so well.
I've been thinking about Seraphim's test today.
Yes, I know - I should think less.
One more thing - Jnat slurry breaks when it's worked, sure. But sometimes, at least this is how it seems to me, it really has to be worked to death to get it 'there'. When the slurry is 'there', then you get the edge results that some of us prattle on about. I don't know that Awase slurry on film is going to get 'there' without adjusting the testing method a bit.
Not that a Jnat edge isn't its own thing, but its more like the zen thing plus the Je ne c'est quoi the edge has.
Think about it - the edge has to split a hair effectively and efficiently.. it has to do it close to the skin, and it has to not abrade the skin past a certain point. That's just about the whole enchilada.
Ok, so - like, how sharp does it really need to be to do that? There has to be a limiting factor of how sharp is sharp enough to cut the whisker cleanly. The action of refining the edge by dimensions expressed in sub-micron units of measure has to be governend by the laws of diminishing returns. They must also, simultaneously, be governed by un-chartable variables such as the steel's ability to hold the edge and whiskers resistance to being cut.
Realistically, there can't be much of an 'improvement' in an edge past a certain point. I really do believe that a lot of the 'mystique' in these stones stems from the owner's sense that they feel more attached or connected to it for some reason. As a result, the owner hones better because of this. Yes, I do believe that Jnat slurry can be much finer than Coticule slurry or perhaps anything else out there. How much finer, I don't know - but I don't believe that the abrasive particles from any natural stone is going to surpass the 30k mark (and still cut) when honing a razor. Maybe I'm mistaken, but I'm hard pressed to digest the concept of abrasive particles breaking down one complete order of magnitude and still working at a perceptible level. But - again - perhaps I'm wrong and that is exactly what happens. I've decided to keep an open mind about such matters, and that's why this experiment is so interesting to me.
Still - Jnats are, technically, no easier or harder to hone on than Coticules, synths, pastes, or whatever. All those other honing options seem to be able to offer edges sharp 'enough' and in some cases 'too' sharp for one's skill level.
Still - I think my personality 'clicks' with Jnats better. I also click with Coticules, Eschers, and synths - but not the same way. That's the emotional thing... it's like that perfect pair of sneakers that you could always jump higher or run faster in because they fit so well.
I've been thinking about Seraphim's test today.
Yes, I know - I should think less.
One more thing - Jnat slurry breaks when it's worked, sure. But sometimes, at least this is how it seems to me, it really has to be worked to death to get it 'there'. When the slurry is 'there', then you get the edge results that some of us prattle on about. I don't know that Awase slurry on film is going to get 'there' without adjusting the testing method a bit.
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1) 'Steel on Stone' - what works for me. Call it a primal thing or something.
2) Lapping film - while I'm sure it works very nicely - it seems kind of like trying to buy nice produce from Wal-Mart. It may be great, but the vibe is weird.
3) Lapping film with Jnat slurry - like trying to learn Spanish from an English-French dictionary. A lot of information, but all kind of confounded....
2) Lapping film - while I'm sure it works very nicely - it seems kind of like trying to buy nice produce from Wal-Mart. It may be great, but the vibe is weird.
3) Lapping film with Jnat slurry - like trying to learn Spanish from an English-French dictionary. A lot of information, but all kind of confounded....
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Couldn't say it better.
Also, don't be surprised you get better results with a system you have used for years, every day, and for a lot of razors, than with one you are only starting out, and noone ever tried before you
We were trying for the Nobel Honing Prize. I accept the blame for the hare brained idea
