Tomonagura confusion

[Claude]

I am struggling to get my head around the right approach to building a tomonagura slurry. I understand that this should be used as the bridge between the final nagura slurry (probably either mejiro or koma) and just plain water without any slurry.

In reading up I have found several suggested options and would be grateful for some clarification:

1) A small separate piece of the same finishing stone. The slurry generated is obviously the same as the finishing stone and has the benefit of not leaving scratches (on the stone)

2) A small piece of a harder j-nat. I assume would act the same as above, i.e. slurry is from the primary finishing stone and doesn't leave scratches

3) A fine diamond plate / card such as DMT1.2k or Atoma. Again, slurry comes from primary finishing stone but can leave scratches. I know there was some recent debate on the impact of the scratches and that So uses this technique

4) A piece of another softer (but also very fine) finisher. I assume the slurry would come from this "nagura" and not the primary finishing stone and is therefore just a very fine nagura (like koma etc). I understand that this is what Stefan (mainaman) uses from his recent videos although I saw a post on foodieforums where he mentioned using a diamond card

Option 1) would appear to be the best but how many people actually have a separate small bit of their expensive j-nat finisher?

Thanks in advance for the guidance.

Claude

[zib]

Maxim sent me Tomonagura with my Shoubudani. Tomonagura literally means "small piece" I believe of your same stone" I may be mistaken... Most vendors supply you with a Tomonagura. That is the preferable method and the one I'd always opt for. Scratching the surface of such a fine finishing stone, (I'm assuming you have something like Oozuku or Shoubudani?) is not good. The surface of my stone is like glass, there are no scratches.. I'd recommend contacting Maxim or Teshiba-san and asking them for a slurry for your stone...They may have one...it's worth a shot...

Here's a pic of mine, Tomonagura at top. This is before lapping, Kanji is still present. The thing with this stone, is it's fineness. I do use a Diamond plate, DMT 325 to generate slurry on other stones, Like Naniwa's, but they're nowhere near 60k grit.... I pretty much have matching slurries for everything else...

If the other's say they are doing the Diamond plate with good results, Well, then you have another option....
Stefan is the one's that pretty much brought this method to the limelight, I'd listen to him...

[JimR]

You seem to have a good grasp on it, actually.

Basically, a small piece of "similar" finishing hone is what you're looking for. It's vanishingly rare to have one identical, i.e. saw off a piece of your hone for use as a slurry stone, so you can discount that.

Another finishing hone with no impurities or wild variations is probably best. A little softer is ok, but if the tomonagura is much harder you run the risk of scratching your hone.

[mainaman]

For razor honing, I used to use perforated DMT 1.2k for slurry making. I stopped using diamond plates long ago because I did not like the results very much, I use tomoagura exclusively now.
You can try each approach and see what you like best.

[Claude]

Maxim sent me Tomonagura with my Shoubudani. Most vendors supply you with a Tomonagura. That is the preferable method. Scratching the surface of such a fine finishing stone, (I'm assuming you have something like Oozuku or Shoubudani?) is not good. The surface of my stone is like glass, there are no scratches.. I'd recommend contacting Maxim or Teshiba-san and asking them for a slurry for your stone...They may have one...it's worth a shot...

The stone I am using is an Oozuku Karasu I got from Morihei



Morihei's advice was to go from mejiro to plain water. I have done this and have got great results but I am interested in playing around with the options. I previously bought a Wakasa Karasu from Maxim which did come with a tomonagura (I think it is a piece of the same stone) and I may try use that.

Claude

[infamous]

You seem to have a good grasp on it, actually.

Basically, a small piece of "similar" finishing hone is what you're looking for. It's vanishingly rare to have one identical, i.e. saw off a piece of your hone for use as a slurry stone, so you can discount that.

Another finishing hone with no impurities or wild variations is probably best. A little softer is ok, but if the tomonagura is much harder you run the risk of scratching your hone.

Maxim has a really nice hard shoub with a corner broke off that can be used as an identical tomonagura. I kinda wish I had bought it when I had the cash.

[zib]

Try it, See what kind of results you get. You never know.

[Disburden]

I am struggling to get my head around the right approach to building a tomonagura slurry. I understand that this should be used as the bridge between the final nagura slurry (probably either mejiro or koma) and just plain water without any slurry.

This statement is confusing me . If you mean tomonagura slurry comes before mejiro or koma, that is incorrect, tomonagura/honzan slurry is the final slurry. For example this is my order of nagura:
Botan
Mejiro
Koma

Final tomonagura oozuki asagi slurry on the same stone.all the other stones prior are less fine...

[DrNaka]

Before you use the slurry of the nagura be sure that your stone is mirror smooth.
I have discussed this matter with onimaru-san here:
http://straightrazorpalace.com/hones...bie-asagi.html

You can use mikawa nagura, the tomonagura from maxim, your other stone wakasa or a kitchen knife blade to make your Ozuku smooth.
You can use your fine diamond stone if it is torn enough but I think you get more smooth finish on your stones with other Jnats.
Just try out and find your "necessary smoothness" as Onimaru-san describes. I do not think that you get this necessary smoothness with a new diamond.

For the slurry you can use mejiro or tomonagura.
Or a very very torn diamond which do not alter your stone smoothness.
You will use water only for the last stage so the nagura you make slurry is not so important (if you have asano stamped mikawa nagura or tomonagura) .

Anyway it is very important to have a very smooth surface.

There are pro and con of tomonagura softer and harder than your stone.

softer tomonagura
Pro: it will not dish your base stone so much.
Con: It will take more time to smooth the scratches which are made by coarse diamond which you used to flatten the stone.

harder tomonagura
Pro: You get more slurry from your stone and it works faster.
Con: Your stone dish more and it may make deep scratches on your stone.

[infamous]

The worst is when you get a huge deep scratch in your stone while you are making a slurry with your tomonagura and you have no idea where the offending particle came from. That happened to me the other day the first time I tried out the huge nakayama tomonagura I got from aframes tokoyo. Thankfuly I had the sense to try it on a pretty crappy kitta I had. I'm afraid to use that nagura again even though it may have not been the naguras fault. This is the danger in using nagura from someone you don't know really well.

Always test nagura out on a cheaper stone before you use it on your best finisher.