What's new

Split Stone

The quality of the edge gets better as the slurry is allowed to concentrate - ie the longer the slurry concentrates and is honed on, the finer it gets. Some slurry stones go up to 30,000 grit. With lower grit stones, the hone cuts quickly when the slurry is first raised, but the edge is not as good - as the particle size becomes finer the edge gets finer, so you can use the same japanese natural stone after, say, an 8000 grit hone or less and go on all the way to a very finely polished edge on the one stone.

Regards,
Neil

That does not make sense. Please explain why that is.

Unless your saying that the finer grit the stone, the better quality the slurry, thus the better quality edge.

I'm reading it as saying "slurry will give you a better edge than no slurry."
 
That does not make sense. Please explain why that is.

Unless your saying that the finer grit the stone, the better quality the slurry, thus the better quality edge.

I'm reading it as saying "slurry will give you a better edge than no slurry."

Its not just me who says it Leighton - a lot of people who use them say it - try googling the relevant terms. I'll come back with anything I find later...
 
Its not just me who says it Leighton - a lot of people who use them say it - try googling the relevant terms. I'll come back with anything I find later...

Japan Woodworker site: Final Steps

After the scratches have been removed by the Aoto, the final step is to hone the edge on the Awaseto until the wire edge disappears and the bevel is well polished. The most effective polishing action is obtained by first rubbing a Nagura stone over the surface of the Awaseto.

SRP: Have you tried producing a slurry with a nagura stone? This should produce the correct grit and be less agressive. In order to get the most out of natural or natural "type" stones, you need to do this; unlike the Shaptons.

Japan Shave Blog: People who are familiar with Japanese hones will have heard the word "Nagura" before. Those who haven't, well, basically when you use a natural Japanese stone to sharpen things, very often it will have a smaller stone with it that you rub all over the surface of the hone to make a thin mix of water and grit rubbed off that smaller stone. The smaller one is called a "Nagura". This is used in traditional Japanese honing to help increase the range of a hone's effect--often, a hone with a nagura will polish faster and more smoothly than just a hone itself.

Mainaman (contributor): With my finisher with slurry I am able to get a razor from 5k stone all the way.

JimR, SRP: Oz, it is my understanding as well that the slurry is what breaks down...

Toyamaryu.org: Slurry is formed on the top of the stone as it breaks down. This paste acts as a lubricant and as an abrasive. The stone needs to be periodically re-wetted. Use water with dissolved baking soda to keep the stone wet. Don’t wash the paste off the stone. Use your hand to dip water onto the stone and keep the blade clean. A small rag can be used, but be careful not to leave thread or other pieces of debris on the stone or blade. You will need to switch water when you switch stones or the coarse grit in the water will leave scratches in the blade. The finer stones need to have a paste formed with a nagura stone to work properly. The nagura stone is soaked with the water stones and rubbed on the top of the finish stones to form a paste.

KevinT, SRP:
If you wonder what smoothing effect a finer stone slurry may add-you could try some awasedo milk on your 8 or 12k

IanS, SRP: the proper way to use a finishing japanese stone is to get a slurry, continue honing (grinding it down) and letting it concentrate so that you're honing on something similar to a very fine grit paste.

Hi_bud_GL in answer to IanS: This is correct.Longer you use better edge you will have.


Theres tons more - you just have to type the words in to your search engine and read what comes up. Lots of it is in affirmation, lots of it is against. That's often the way it is when people describe subjective rather than objective things - I think we all realise that from postings on forums such as this.
 
What? Obviously slurry cuts faster and is more effective in terms of time. My question was why does slurry make a better/sharper edge than no slurry.

The japan blog quote states your position in an indirect method. It says it makes the edge smoother. But smoother compared to what? No slurry? Smoother and duller? Smoother and sharper? Again, smoother relative to...?

I'm open minded, but all the evidence and experiments I've done point to slurry making the stone grit act as a coarser stone, not finer.
 
What? Obviously slurry cuts faster and is more effective in terms of time. My question was why does slurry make a better/sharper edge than no slurry.

The japan blog quote states your position in an indirect method. It says it makes the edge smoother. But smoother compared to what? No slurry? Smoother and duller? Smoother and sharper? Again, smoother relative to...?

I'm open minded, but all the evidence and experiments I've done point to slurry making the stone grit act as a coarser stone, not finer.

What??? So many questions! And none of them to do with what I originally wrote. Whatever the answer, it doesn't really matter if one finds the resulting edge "better" - another highly subjective term. There's a lot more info on the web, like I said, I'm happy to leave it there for those who want to put in a little effort and find it.
 
what SORT of slurry? Belgian slurry is garnets that don't cleave, japanese slurry is grains that DO cleave. they're not identical in action. I'm aware that japanese slurry takes polishing to a higher level once it begins to break down, but to get the 'final polish' with belgians you'ld likely wash off the slurry and hone with water.

Garnets act differently than other abrasives. Even other natural abrasives, or maybe I should say, especially other natural abrasives. Whether there are similar significant variations in the types of stone used in Japan, I've no clue, but it wouldn't be wise to make assumptions.

I can appreciate your confusion. There's a tendency to make assumptions across the range of natural stones, that turn out to be incorrect. I've stumbled onto capabilities that weren't at all obvious to me at first
 
What? Obviously slurry cuts faster and is more effective in terms of time. My question was why does slurry make a better/sharper edge than no slurry.

The japan blog quote states your position in an indirect method. It says it makes the edge smoother. But smoother compared to what? No slurry? Smoother and duller? Smoother and sharper? Again, smoother relative to...?

I'm open minded, but all the evidence and experiments I've done point to slurry making the stone grit act as a coarser stone, not finer.
Interesting points, but the initial slurry is the same grit as the particles that are bound in the stone, when you work the slurry it gets finer and finer and you end up with particle size that is a lot smaller than what you started with. If am wrong here please correct me. My argument here comes from my experience with my Asagi. With slurry I get that sandblasted looking bevel with no slurry a scratched bevel. So said that Asagi is scratchy and when used with no slurry it takes a lot of skill to avoid the scratches on the bevel. If anyone can use Asagi like that I am interested to read their impressions.
As fart as slurry vs no slurry, when I talked to So about that he said that slurry will slightly round the edge thus producing longer lasting edge, no slurry will give you the ultimate wedge shaped edge but probably not as durable as with slurry. I can't comment on that since I have not shaved with the same razor more than a few times but with slurry the edges I get are great for my taste and really do not need improvement in terms of sharpness.
I would like to hear what other memebers experiences are.
 
I only have experience with one fine Japanese natural hone and a nagura stone so I don't know if this is typical or not. The hone itself is very slow and gives a very smooth edge that is not necessarily sharper. The nagura stone is another type of stone altogether with very fine particles. When I make a slurry with it, very little of the material comes from the hone (I can tell because the stone is dark and the nagura light). The nagura slurry does definitely break down over time and the edge it provides is incredibly sharp. In this case, it is the nagura slurry that is doing all the work and the hone is just a smooth surface for it to work on. It's not at all comparable to the situation of a coticule, where the slurry is the same composition as the surface of the hone, only more so.
 
I only have experience with one fine Japanese natural hone and a nagura stone so I don't know if this is typical or not. The hone itself is very slow and gives a very smooth edge that is not necessarily sharper. The nagura stone is another type of stone altogether with very fine particles. When I make a slurry with it, very little of the material comes from the hone (I can tell because the stone is dark and the nagura light). The nagura slurry does definitely break down over time and the edge it provides is incredibly sharp. In this case, it is the nagura slurry that is doing all the work and the hone is just a smooth surface for it to work on. It's not at all comparable to the situation of a coticule, where the slurry is the same composition as the surface of the hone, only more so.
Interesting, when I talked to So about nagura he recommended to us DMT for slurry. He said that no nagura is as fine and will scratch the bevel of the razor. Some people say that there is a ngura that is very fine and works just great.
 
Interesting, when I talked to So about nagura he recommended to us DMT for slurry. He said that no nagura is as fine and will scratch the bevel of the razor. Some people say that there is a ngura that is very fine and works just great.

Mr. So may very well be correct as I don't have any kind of microscope to look at the bevel and am just relating subjective impressions. The way I measure the sharpness of my razors is by how long the BBS lasts, with acceptable being 8-10 hours and exceptional being 12+. I also wonder if the smoothest bevel actually results in the closest shave ... smoother definitely ... but maybe not sharper. In any case, the slurry from my nagura does get finer and finer because it gets embedded in the skin of hand in a way that coticule slurry doesn't.
 
Top Bottom