Adventures in Japanese natural honing.

[BDF]

I have been honing on synthetics and pasted balsa for years with good success, at least in the end. Several weeks ago, I purchased a Jnat from a member here (thanks Steve!) and have been frolicking with it since. An interesting journey so far. Of course at first I could barely get an edge on a razor and certainly not a shaving edge but in the last week or two I finally stumbled on what I was doing wrong and have successfully put a shaving edge on several razors. Not the best edges known to man but sufficient for a reasonably close, comfortable shave even ATG. I have a couple of razors that Alfredo put a Jnat edge on quite a few years ago and while quite sharp and smooth, they do feel different than razors honed on extremely fine synthetic abrasives. First of all, I find that stropping is not beneficial on a razor that has been wiped on 0.5 micron Cr2O3 or 0.1 CBN pasted balsa. But it is not only beneficial on a razor honed on a Jnat, it is required to get a sharp, smooth edge. Further, additional stropping on a Jnat edge is beneficial while again, not much at all on a very fine synthetic edge.

It seems that there is a tooth or a set of grooves that grab hair out of proportion to the pressure used on a Jnat edge. In other words, the razor cuts much better than it should based on the feel of the blade against the skin. A synthetic edge can actually be sharper and yet takes a bit of pressure to actually cut hair. Both are smooth and comfortable to me, even shaving against the grain.

Certainly not jumping into the 'which one is better' ring here, just mentioning how I perceive at least some of the differences between the two edges. And of course this is based on a couple of Alfredo's edges from years ago, and my recent humble attempts with the only Jnat I have ever used. So no global, overall judgement but rather an early report on how they behave in my view.

Now if I can just avoid buying a pile of rocks just to see how they work, all will be well. So far, no problem ignoring that rabbit hole although I do have my eye on a different, more local stone that supposedly works well. So maybe just one more stone.....

 

[Herrenberg]

Now if I can just avoid buying a pile of rocks just to see how they work, all will be well. So far, no problem ignoring that rabbit hole although I do have my eye on a different, more local stone that supposedly works well. So maybe just one more stone.....

Ah, that sounds familiar. Welcome to the rabbit hole.

"Buying a pile of rocks just to see how they work" might be the title of my autobiography, if I ever write one, which I won't.

 

[H Brad Boonshaft]

Stropping any edge will always improve it. if stropped properly.” Wiping” an edge on a pasted paddle strop, is stropping. So not any wonder that it improved a synthetic edge. Paste can cure a lot of honing sins.

You really cannot compare your first shaving Jnat edge to one of a honer with years of experience on a Jnat, especially if you had issues getting the razor to shave off a Jnat. It not the stone, there is probably a little skill involved on Doc’s part.

The easiest way to get a good Jnat edge is to finish the razor with a solid 8k shaving edge. When you can consistently improve an 8k edge with good shaving Jnat edge, then you can experiment with more advanced Jnat edges, (1k bevel set to smoking Jnat edge with just diamond slurry).

A year from now your Jnat edges will be as good or better than CBN edges. I doubt you will find a local stone that will outperform a Jnat.

You just need to spend a little more time with your stone, experiment with diamond slurry thickness and pressure. You do need some pressure to start and as the bevel improves and the edge gets straighter you ease up on the pressure and thin the slurry to straighten the edge.

Jnats can be as simple or complicated as you make them.

 

[Tomo]

If Jnats are a rabbit hole then Mount Everest is a mole hill.

A fascinating topic that you could spend a lifetime studying.

 

[Tomo]

although I do have my eye on a different, more local stone that supposedly works well.

What is your local stone?

 

[Green Bob Shaving Newbie]

Interesting.... what stone are you using?

 

[cotedupy]

Enjoy the ride!

Some random thoughts, that may or may not (probably the latter) be of interest in terms of how you think about them.

Compared to other whetstone-producing countries Japan has huge breadth. They produce stones made from all sorts of different things; shales, sandstones, metamorphic, igneous... pretty much everything basically. About the only generalisation I could make about jnats is that they're not particularly good sharpening, particularly in low and medium grit ranges.

They are pretty good at finishing a razor though. This is because there are certain types of Japanese stone that really nail a sweet spot between cutting (abrasion), and refinement. Japanese razor finishing stones are shales (mudstones) pretty much exclusively I believe, let's compare them to a couple of other general types of popular razor finishing stone - novaculites and slates...

Novaculites are a type of pure silica that has kinda been fused together and it cuts like crazy; a fresh hard/translucent is aggressive, and leaves a pretty grippy edge. It's why people burnish the hell out of them when they get them if they're using for razors. I use them on knives occasionally and I do the opposite - I rough up the surface on an atoma. Slates are shales that have been compressed and transformed with heat and pressure, which tends to have the affect of flattening and smoothing the silica in the stone, making them cut slowly. They lean more toward polishing and refinement than they do abrading.

Shales are basically compressed, or 'lithified' mud. The nature of the initial mud deposit and extent of lithification can vary a lot, and shales can go all the way from very hard to very soft, and very fine to very coarse, at which point they might start tipping over into what we'd call 'sandstones'. If the initial mud has a high silica content it will cut better, equally if the stone is softer more of this will be released in use and it will cut quicker.

You do not want a soft stone as a razor finisher, as it will release too many particles and introduce an element of randomness. Certain types of jnat work well because they are very hard for shales, yet with a high enough silica content of reasonable abrasive power that it will still put an edge on a razor, rather than just smoothing out what's already there.

---

Almost all natural sharpening stones get their abrasive properties from silica/quartz, which has a hardness of 7 on the Mohs scale, which works because hardened steel is around 6. The majority of synthetic stones get their abrasion from Silicon Carbide (SiC), or Aluminum Oxide (Al2O3), or a combination of the two, both of which are around 9 on the Mohs scale. They are inherently better at abrading steel.

Another member made a simple, but perceptive, comment on a thread a little while ago when they said that synthetic stones don't give as good a razor edge as the best natural stones because they're not designed to. In fact they're designed not to - they're designed to sharpen things by abrading them. If you want a synthetic edge that starts to mimic a fine natural stone, you need to go to a way higher grit level than you'd find in the natural stone.

I've never used a diamond / other paste but it makes sense that it would work well - diamond is, obviously, very hard, so very fine pastes might cut as well as considerably coarser natural stones based on silica. And the fineness of the particles might mimic some of the refining properties of a natural stone. Which is a fairly complex formula based on the composition of the bind, and how it works.

---

An interesting side note to all this... the very 'best' or most expensive Japanese natural stones are not really prized for their honing or sharpening abilities, they're valued for their polishing abilites on kitchen knives and Hatana, and pretty patterns on the stone. You can pull a mirror finish on steel out of very fine diamond paste, but the very best Japanese stones might be able to put a bright mirror on hard steel, and a dark haze on soft steel, creating 'kasumi' contrast between the two. The best stones for this might be quite fine, but slow cutting, and slightly softer and more friable than a razor finisher.

Long story short... there are huge number of variables in natural stones, even within the same type. And when they work together in the way that you want, synthetic stones or solutions are a little one dimensional in comparison. Though as you've noted above - when taken to extremes the results of very fine pastes can be extraordinary (as I say; I've never used one, but have no reason to doubt it). A natural edge may be less fine, but more refined, with the two working equally well but in slightly different ways.



[I'm not a Jnat exert by any means, but I have a few and have used quite a lot of various types. The above is just my thoughts and experiences, and probably all quite obvious anyway.]

 

[BDF]

For those asking about the stone, I really do not know much about it. It was purchased from a member here, based on advice about that person from Alfredo (Doc226). The gentleman who sold it to me says it is a good finisher for razors. It is a Nakayama stone, gray in color. No idea what type of Nakayama nor any idea where it came from.... other than Japan I suppose As this is the very first and only Jnat I have ever used, I just do not have any opinion about it nor can I gauge it regarding hardness, fineness or anything else. It feels very hard to me but then again it IS a rock. It slurries OK and cuts well enough but it is not as aggressive as the stones in some (most?) honing videos and takes a while to generate any swarf from the razor. The gentleman also sent along a small rubbing stone that appears to be the same or a similar stone and that stone generates a coarser slurry than the base stone does when slurried with a diamond hone. The stone is almost shiny when dry and leaves a surprisingly shiny bevel on a razor. This was a surprise to me because the few Jnat edges I have are a bit cloudy. This stone produces finishes that look like a razor honed on very fine synthetics.

I did manage to get a very impressive edge on a Red Imp, comfortable even ATG and yielding a very close shave.

I was thinking about picking up another whetstone (not a Jnat) but I think I will be better off using one stone this early on, no need to introduce more variables. This stone can yield an excellent edge so I will keep using it on different razors to build skill.

 

[cotedupy]

For those asking about the stone, I really do not know much about it. It was purchased from a member here, based on advice about that person from Alfredo (Doc226). The gentleman who sold it to me says it is a good finisher for razors. It is a Nakayama stone, gray in color. No idea what type of Nakayama nor any idea where it came from.... other than Japan I suppose As this is the very first and only Jnat I have ever used, I just do not have any opinion about it nor can I gauge it regarding hardness, fineness or anything else. It feels very hard to me but then again it IS a rock. It slurries OK and cuts well enough but it is not as aggressive as the stones in some (most?) honing videos and takes a while to generate any swarf from the razor. The gentleman also sent along a small rubbing stone that appears to be the same or a similar stone and that stone generates a coarser slurry than the base stone does when slurried with a diamond hone. The stone is almost shiny when dry and leaves a surprisingly shiny bevel on a razor. This was a surprise to me because the few Jnat edges I have are a bit cloudy. This stone produces finishes that look like a razor honed on very fine synthetics.

I did manage to get a very impressive edge on a Red Imp, comfortable even ATG and yielding a very close shave.

I was thinking about picking up another whetstone (not a Jnat) but I think I will be better off using one stone this early on, no need to introduce more variables. This stone can yield an excellent edge so I will keep using it on different razors to build skill.

Sounds very nice!

Nakayama is the quarry, so that's where it's from within Japan. A grey, or blue-grey Nakayama finishing stone would be called 'Asagi' or 'Mizu Asagi' (which describes the colour).

 

[BDF]

OK. As I said I am extremely ignorant about natural stones, Japanese or otherwise. That is why I appreciated a couple of the folks here for helping me out and setting me up with a stone that should work for razor honing. Otherwise I would have to go to AFramesTokyo and hope for the best although how would I even begin to make reasonable choice? Is a $1,800 stone really worth the cost? How about a $3,000 rock? Can a perfectly useable stone be had for $100?

This is what the stone looks like. This photo was taken by the seller. It is a little bit more gray than it looks in the photo. Pretty large stone and very thick although a bit on the short side. It makes a nice bench stone though not really applicable to holding in the hand- it is quite heavy.

Pretty uniform though it does turn a sandy color on one edge, and that edge also has a translucent material right at the edge. Looks almost like a piece of quartz perhaps. Very consistent surface and while it does have a small area of tiny bubble shaped pores in it, overall it is homogenous and consistent across the stone.

 

[cotedupy]

I don't think your picture uploaded properly there, but the way you describe it, with the sandy colour coming in at on of the edges, is quiite typical of Nakayama Asagi as far as I can see.

Re price - You don't have to spend silly amounts of money, no. Like everything jnat prices is dictated to a certain extent by scarcity, and the most expensive ones are not necessarily going to be razor honing type stones anyway. They're for doing certain things to polish swords and knives. If you try to polish on some mega-hard Ozuku razor stone it's going to be terrible. The other thing which drives price as I mentioned is visual appearance; when you see jnats with very long names - most of that is describing colours and patterns on the surface of the stone.

If you like your stone (and a Nakayama Asagi should be an excellent razor stone), and want to experiment more without spending a huge amount on another full-size stone, then something that's worth trying out is different types of nagura. I'm quite new to nagura, as you wouldn't use them so much with knives, but it seems a very interesting area. The tomo Nagura you have will be very hard and fine, but you can get different types of softer ones - look out for Mikawa Asano - and play around with the results they give.

FWIW - my favourite razor finisher is a stone that I think is possibly a Nakayama Asagi (though I have no way of telling). It's superb.

 

[H Brad Boonshaft]

Photo does not load.

Pricy Jnats are based on the type of stone, size, appearance, provenance, (Collectability) and the stone dealer’s advice, which can be more valuable than the stone.

Small clean (plain) stones can easily be had for around $100. Chef Knives to Go sells a (small) Koppa Nakayama for $85 that will easily hone a razor. They sell out in hours once in stock, so you must get on their Email list to be notified when in stock.

You do not need an 8-inch stone to finish a razor.

Take a look at Alex Gilmore’s videos on JapanStones, for great, no nonsense how to hone on a Jnat advise, (Axe method of honing razors)

With a Diamond plate and your tomo nagura you already have all you need.

 

[BDF]

Not sure why the photo is not showing up for some as it is visible to me. ??

Anyway, let's try this way to post a photo.

Edited to add: The stone is a bit darker and more gray than it shows in this photo.

 

[Steve56]

I could see the image.

 

[cotedupy]

Not sure why the photo is not showing up for some as it is visible to me. ??

Anyway, let's try this way to post a photo.

Edited to add: The stone is a bit darker and more gray than it shows in this photo.

Pretty! Certainly looks like a Nakayama Asagi. You probably wouldn't call it 'Mizu' (which means 'water' and is a colour description).

Nakayama stones are very well liked, and never cheap, so it sounds like you've started with a good one .

 

[Empire straights]

Pretty! Certainly looks like a Nakayama Asagi. You probably wouldn't call it 'Mizu' (which means 'water' and is a colour description).

Nakayama stones are very well liked, and never cheap, so it sounds like you've started with a good one .

I'm so interested in jnats but I'm so scared to jump down that money pit. I think if I could find a semi soft, very fine koppa I could stop there. Like all the rest of the jnat junkies.

 

[BDF]

I was fortunate that two gentlemen from this forum guided me and helped me out with a Jnat as I have absolutely no idea what I was looking for and even more importantly I would not know if a poor edge was me, the stone or both. Now I have some confident it is me making the fair to good edges.

Cost was not the goal in buying this rock but rather getting a decent, hopefully good or even better stone was. So the price was not really important and I was not hunting a bargain. That said, it was not overly expensive anyway so I am very happy with the stone. It is a bit on the short side though plenty long enough to hone on, and definitely not a hand- held stone as it is thick and heavy. The gentleman who sold me the stone offered another one that looks very interesting but I am trying to avoid variables right now so plan to stick to this stone for a while at least, perhaps my only Jnat in the future also.

It is amazing how different honing on a stone is compared with honing on film. The best way I can describe it is that while it seems that firm, thin film on top of a glass plate would be very rigid, a stone is much, much less forgiving. It is harder to get the entire edge contacting through the process. Not sure why this is but this is what I am learning.

Pretty! Certainly looks like a Nakayama Asagi. You probably wouldn't call it 'Mizu' (which means 'water' and is a colour description).

Nakayama stones are very well liked, and never cheap, so it sounds like you've started with a good one .

 

[BDF]

Honed a no- name razor with the same blade size, grind and profile of a Red Imp hollow ground razor on the Jnat. The edge did not seem that great but it was undercutting slurry and starting to stick to the stone so I thought those were good signs. After stropping, it did not feel uber- sharp to me but when shaving with it, it was very sharp and smooth much to my surprise. Not as sharp as extreme grit synthetics but still a great shave, even ATG. Only problem is that this is a New (old stock vintage) razor with a spike point and I forgot to mute he so a couple of little red streaks during the shave. This is probably my fault and not the stone's fault . That is probably what you get for $3,000- a stone that jumps off the table and mutes your razors for you.

 

[Steve56]

You can bump the keenness a bit with some clear water strokes at the end.

Also try your last finishing strokes on thin slurry going with very slow and shorter strokes - Iwasaki said that made the pressure go away and he is right.

 

[BDF]

This is an interesting learning curve, trying to use a Japanese natural to hone a razor to a shave ready, or better yet, a fantastic shaving edge. After a lot of stumbling and fumbling, I went back and watched a bunch of honing videos to try and pick up some type of method or at least a direction. And I think I have a recipe that works.....

Coming from film and pasted balsa, a Jnat is very unforgiving and requires a lot of attention to blade placement, pressure and blade torque. But I think I did pick up clues toward a useable method from honing videos, and here is what I have found (note: I have been using a Jnat for a couple of months so none of my info. is certain and some or all of it may well be wrong).

The big thing I have found as a path toward success is torque applied and watching the blade undercut slurry or water. So what I have been trying is this:
1) make a fairly dense slurry. Apply a bit of torque and lap the stone with the razor. As the edge moves toward fully undercutting the slurry, back off the torque a bit. The edge will stop undercutting the slurry but keep lapping the stone with the same reduced torque until the edge again fully undercuts the slurry. Continue this progression (less torque and laps on the stone until the edge fully undercuts slurry with the new, lower torque) until the razor fully undercuts the slurry with <almost> no torque.
2) Thin the slurry with water. The edge will not fully or sometimes not at all undercut the slurry. Add torque until it does undercut the slurry. Then back off the torque a bit and hone until again the entire razor undercuts slurry with <almost> no torque. At that point, again dilute the slurry.
3) Repeat the above process until the slurry is almost fully diluted, staging the torque as needed to achieve full undercut. As the slurry nears clear water, it will begin to suction down to the stone. At that point I have been adding perhaps 20 full strokes on the stone with very little pressure and torque. By this point, a clean razor will tree- top albeit poorly. Still, it is a marker for me to stop honing and go to stropping.
4) Strop on linen, maybe 35 laps or so and then somewhere between 30 and 50 laps on leather. Then it will tree- top quite well although not as well as, say, a razor finished on very fine pastes on balsa. Still, I have found a Jnat edge to have a different type of shaving than an uber- grit finished razor. It is not as sharp but has a property I can only describe as having 'teeth' that grab and cut hair beyond its inherent sharpness.

Color me happy to have found a repeatable path to honing on a Jnat, at least the Jnat I have as well as several razors I have been honing on it.

As always, many thanks to those who post instructions as well as videos about this. This is just not how film reacts and pasted balsa is so forgiving that it really requires very little technique or skill to use. And pastes on balsa are very, very effective. But this thread is not about what method(s) is best or even preferable but rather about a person who learned to hone on film and pasted balsa trying a completely different method- a Japanese natural. I am not searching for a 'better' way to accomplish a thing but rather trying out a completely different method just for the sake of trying it.

For whatever it is worth, even if I go back to pasted balsa, I really do like the wide range that a Jnat covers almost effortlessly- from a 1,000 grit bevel set all the way to shaving sharp with one stone.... kinda' nice coming from film.