Synthetic Nagura - better understanding requested

Hello everyone,

I'm hoping to get some answers on why synthetic nagura sometimes I have grit ratings? I know that these nagura are more of a cleanup stone/correcting stone, but I do not understand why the grit rating. I know that with the asano nagura there is a progression (typically botan --> tenjou--> mehiro --> komo [sorry for the spelling]) but I have heard that these synthetics are not for progression and to make a slurry from them will pollute the slurry with larger grit than desired. So am I correct, and if so why the grit ratings. I am posting an example in hope for y'all to have an example of what I'm looking at and talking about.

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Synthetic stones are man made and consistent so their performance is known and they can be assigned a grit. Natural stones are not consistent and only through use by many people can a particular stone be characterized as a finisher or pre finisher etc. Over time locations produce certain stones and those pieces from those location get a reputation. A Coticule for instance has no assigned grit rating and you will see members talk about them depending on the location in the mine they are from and the time they were mined. Some say they are fast others say slow some are great finishers and some not so much.

Also grit ratings are somewhat different from certain countries to others especially from the East.

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Originally Posted by thebigspendur

Synthetic stones are man made and consistent so their performance is known and they can be assigned a grit. Natural stones are not consistent and only through use by many people can a particular stone be characterized as a finisher or pre finisher etc. Over time locations produce certain stones and those pieces from those location get a reputation. A Coticule for instance has no assigned grit rating and you will see members talk about them depending on the location in the mine they are from and the time they were mined. Some say they are fast others say slow some are great finishers and some not so much.

Also grit ratings are somewhat different from certain countries to others especially from the East.

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Yes I very much agree. However my question is not about the comparison between natural and synthetic but only mention progression as a reference and know that comparing natural progression and synthetic progression is like comparing apples to oranges.

But my question is solely why the grit rating on the synthetic naguras at all. I notice that for them you will find #1000, #3000, #5000, and #8000. But if they pollute slurry and used for cleaning/correcting, then why the grit rating at all. The closest thing I've found is that you match the nagura grit with the base synthetic stone grit, but what does that do? Why can't you use an 800 with a 8000 base or visa versa?

It depends on your goal

They can be used EXACTLY like the Natural Nagura in a progression on a harder higher grit hone..

ie: I can take those marked synth nargura, put them on a Gokuyama 20K and do everything I can do on a Nakayama and the Natural nagura,,,, Yes really

The edge may feel different but the progression works the same

I think, the toppic becomes convolutet, if you use the term Nagura for each of the different uses it serves in this field.

The pictures you chose are typical for different uses: the first one is mainly used to clean the surface of an artificial stone of residue. The slurry created is not meant to serve for a specified use afterwards, so it's mostly used under running water. The second Nagura is meant to create slurry specifically to be useful during sharpening on your artificial stone.

Let's describe the different uses:

cleaning:
mostly coarser, dense stones of a less harder material are preferred, but you can try any stone you have. If it serves your purpose, go for it.

conditioning:
make the surface smooth, break used and dull particles out of the surface. You want to do that with a suitable stone and that very much depends on how hard the artificial stone is that you are going to use the Nagura on. Many times the first type of Nagura you use for cleaning serve in this purpose too.

create slurry:
you create additional slurry before sharpening on your artificial stone. You want a specific particle size for this, otherwise you would get a coarser finish, a step back in your sharpening process. If you create a certain finer slurry, it helps very much to prevent additional loadup of you stone. Mostly you simply wash the slurry of, and the stone surface should be relatively clean. Slurry helps to brak down the swarf particles and it limits a foil burr.

On artificial stones the first to uses don't need a specific grid of the Nagura, the particles are mostly swept down the drain before the artificial stone is used anyway.

But if you intend to use the created slurry for your sharpening process you want it to be of a clearly defined grid size.

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Originally Posted by gssixgun

It depends on your goal

They can be used EXACTLY like the Natural Nagura in a progression on a harder higher grit hone..

ie: I can take those marked synth nargura, put them on a Gokuyama 20K and do everything I can do on a Nakayama and the Natural nagura,,,, Yes really

The edge may feel different but the progression works the same

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:hmmm: :idea: I think I may like trying that out. :y

What Hein31 and Gssixgun said.

They're fun to play with. A while back I was looking for ways to set bevels with a natural stone and expand the low end of my one-stone honing kit. The solution was a marriage of synthetic and natural materials. I grabbed a Naniwa 800 grit hone and lopped off a nagura sized piece.

Bingo.

Now residing in my Cnat tackle box is everything needed to go from bevel set to final polish on that one stone via nagura.

Rlmn. I'm sorry to high jack your thread but I can't seem to figure out how to send you a private message.
I live in White Pine and I was wondering if I could talk you into honing my sr. Pls email me at brian@briansperfectpc.com.

Thank you

It depends on your goal

They can be used EXACTLY like the Natural Nagura in a progression on a harder higher grit hone..

ie: I can take those marked synth nargura, put them on a Gokuyama 20K and do everything I can do on a Nakayama and the Natural nagura,,,, Yes really

The edge may feel different but the progression works the same



That and you may want a progression, to smooth out a high grit synthetic or even Natural stone face.

I use high grit synthetic slurry stones to refresh synthetic stone faces, when I do not want to get up and use a diamond plate at the sink.

I often use a progression of synthetic full size stones, to finish lap stones, both synthetic and naturals. Does it make a difference, who knows? It does not hurt…

Additionally, using Natural Nagura and Natural stones as slurry stones, produce some interesting results.

I recently honed a razor with a Naniwa 8k Junpaku, Snow White, and,Tsushima slurry, with interesting results, a hazy bevel with a super straight edge. It also removed 4k stria quickly.

Many natural stones continue to break down producing much finer finishes. Do not get, so caught up in the look of the bevel, that you forget about the edge.

Experiment and find what works for you.

Not to derail this thread, but from the comments, I'm interested in a range of base stones for use with synth stones cut to nagura size. Gokumyo 20k and a Cnat were mentioned. Perhaps a translucent Arkansas would work similarly? Or frosted plate glass? Any suggestions?

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Originally Posted by Brontosaurus

Not to derail this thread, but from the comments, I'm interested in a range of base stones for use with synth stones cut to nagura size. Gokumyo 20k and a Cnat were mentioned. Perhaps a translucent Arkansas would work similarly? Or frosted plate glass? Any suggestions?

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The PHIGS it really depends on which yours is some are hard and produce nearly zero slurry other will slurry right up

The Arkies are a good playground for slurries

The lapped Spyderco UF is another good playground

There are few threads on here about using Frosted Glass/Glass you need to search them out

Personally I feel the Go20k is a finisher in it's own right that doesn't need anything but a steady hand but hey go play in the mud see what you find :)

Here is a guy doing just that :) http://straightrazorpalace.com/honin...k-refresh.html

Of course after he posts that is is working for him he is told why it isn't :(

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Originally Posted by Brontosaurus

Not to derail this thread, but from the comments, I'm interested in a range of base stones for use with synth stones cut to nagura size. Gokumyo 20k and a Cnat were mentioned. Perhaps a translucent Arkansas would work similarly? Or frosted plate glass? Any suggestions?

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Frosted glass is kind of fun. I got an old glass barber hone, and on inspection figured out that's pretty much all it is. Little guy works just as well as my Arkies, CNat, and JNat as a base for slurry. I've had good success with all of the above and natural stone material. I can only imagine they work equally well with synthetic slurries.

Well, my curiosity got the better of me, so last night I played around with a 1500 trad. Naniwa cut down to nagura size followed by a coticule rubbing stone as slurries on a Dan's true hard Arkansas. 1500 slurry was cutting pretty aggressively and turned to swarf pretty quickly. Rinsed the blade and stone off and switched to a coticule slurry. As I continued, I could really see the bevel start to brighten as the slurry broke down. Then I rinsed off the blade and stone off and tried some laps with the true hard and baby oil.

HHT after stropping wasn't the greatest and the shave wasn't the greatest either. I wonder if this may have to do with the rubbing stones acting as abrasives on the true hard surface, roughening it for the last setion used by itself with oil. Perhaps it would have been better just to stick with slurries and water?

Coticule slurry is a bit weird. Hard garnet that doesn't really break down. You might have discovered what Coticule users refer to as 'slurry dulling.'

I usually try to slip something in between the final Coticule slurry phase and finishing laps. Either thin slurry from a slate or more laps on the finisher, something to help remove any potential rounding that may have been caused by the coti slurry.

Could've also needed a tad more work on the 1500 to ensure bevels were meeting.

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Originally Posted by Marshal

Coticule slurry is a bit weird. Hard garnet that doesn't really break down. You might have discovered what Coticule users refer to as 'slurry dulling.'

I usually try to slip something in between the final Coticule slurry phase and finishing laps. Either thin slurry from a slate or more laps on the finisher, something to help remove any potential rounding that may have been caused by the coti slurry.

Could've also needed a tad more work on the 1500 to ensure bevels were meeting.

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Thanks. The edge was "shave ready" beforehand, so I really didn't need much from the 1500, other than to rewrite things. The coti slurry brightening the bevel at the end made me think it was behaving differently at that stage. Brightening or "dulling" may have had to do with swarf as well. Normally, I use coticules with straight water. My sense still is that switching to oil on the resurfaced Ark surface may have taken things down a notch. I'll try it again in a few days (just rewrote the edge with a small coticule and a honyama and the edge is looking really good), going 1500 trad. Naniwa slurry > coticule slurry > slate slurry to see how it compares.

Ah, so it was just a touch up to play with the technique then? I've never used baby oil so I don't really have a base of reference for that. I've read in places that thick oil is desired for low grit work, and thin for finishing. I do know that pure mineral oil on my coticule made a rough finish, and had to be thinned with mineral spirit to get where I wanted to be. The same might happen with an Arkansas stone.

:shrug:

Ahh, the joys of slurry… so a lot of variables going on. Unknown grit, Grit size, frangible vs hard grit, pressure, base stone grit and slurry thickness.

When finishing look at the edge, more than the bevel, yes the slurry may be polishing the bevel, but damaging the edge.

With Arks, I keep one side burnished for a known finish producing side, use the flip side for experimenting.

Experiment, and look at the edge, it either improves the straightness of edge or not.

Fun stuff, but for me, a hard ark edge,(Black or Translucent) on water, Smith’s, Ballistol, or drop of oil is hard to beat, stone face will affect results.

My Eschers are pretty fast. I tend to use them with water only. 30 laps no pressure and a marvelous edge [emoji4]


Sent from my iPad using Tapatalk

Getting :OT

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Originally Posted by Euclid440

With Arks, I keep one side burnished for a known finish producing side, use the flip side for experimenting

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Indeed, this may be the ticket in this case.

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Originally Posted by rlmnshvstr8

Getting :OT

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Sorry about that. You're right to rein things in.

A Slurry Thread

http://straightrazorpalace.com/advan...rt-slurry.html


Ask away in there, plus there are tons of ideas and opinions over the last 7 years :p