Thread: Help with extremely though coticule

Hi

Some time ago I got a new coticule. La veinette, combo with manganese lines, cloudy blue hues. The stone is hard, very hard. The first slurry stone disintegrated, I wrote the mine itself and got another one. (let me say, the costumer services of Ardennes is first rate).

The second slurry stone seemed to be tougher, but after a couple of months I notices that all the slurry comes from the slurry stone and not the hone itself, so I wrote again to Ardennes and they sent me 2 slurry stones, from the same la veinette vein both combo with BBW and tough as they come.

My problem now is that I cannot make any slurry at all its like rubbing 2 pieces of glass.

I do want to make the hone work, for touch ups its amazing, from hht 0, with dificult shaving to hht4 and amazing shave, it take only 100 laps on water. I would like to use it for the entire sharpening process.

How can I make some slurry with such a hard stone?

Thanks

Well, coticules are very different from one to another. Some stones are producing slurry very easily, others don't (as you saw with yours).

It's not a bad thing having the slurry coming from the slurry stone, and it will indeed help you to use your stone at different steps of the sharpening.

Tough coticules may be good for finishing the job. I would use yours with a soft slurry stone for the begining steps, and with clear water and no slurry at the end of the process.

I think you may lost some of the good properties of your stone if you try to obtain slurry anyway (with a diamond stone for example).

Either get an Ez lap 26F diamond stone and ware it out a bit before using it for slurry.
Either stick to making slurry from a softer coticule slurry stone.

I often runninto this problem with hard jnats...you want to use the stone's slurry but cant get at it with a tomo.

So I currently use a well worn out EZ-Lap 26F 600grit(@1000 after 5 years of use) that does not dropp any grit. This is my go to tomo and slurry stone

How long to make slurry with the hard slurry stones?

Like ovidiucotiga, I have hard jnats and with a similarly hard tomo it may well take 3 minutes of rubbing to get a light slurry, but the results are usually very good.

As far as I can tell, when a jnat seller says the stone is hard and takes 'advanced honing skills', they mean you have to be patient raising slurry and don't push too hard. After all, once you have the slurry nothing else is different. And when you're buying a high-end thin Japanese kitchen knife they'll sometimes say that you need 'advanced knife skills'. As best I can tell, this means not trying to turn the knife clockwise or counterclockwise with the edge in contact with the cutting board.

Neither skill is really very advanced but is just part of using specialized tools.

Cheers, Steve

Like using a Les Latneuses Hybrid stone it is like trying to milk a rock. If you have a slurry stone the same it will give a light slurry, but takes some time and don't push too hard. Based on the fact that you have multiple slurry stones now. I would use them in a progression on your base stone. Start with the softer stone to do the grunt work and finish on the slurry from the hard tomo and base stone to just water. I do this with my really hard coticules and it works very nicely. As Steve said above it can take a bit and seems like you are getting nothing, but it eventually comes up with a light slurry and that slurry still works very well too.

I am fortunate enough to have an antique glass hard Coticule that displays the same characteristics as yours.

I have used different slurry stones with it and can do as the above post says;
" Start with the softer stone to do the grunt work and finish on the slurry from the hard tomo (nagura) and base stone to just water. "

The type/source of the slurry stone seems not to matter, just the grit size it produces. As you say, the edge at finish is a great smooth polish.

It is one of the few Coticules that really soensn't need CrOx to be ready for un-pasted stropping and a great shave!

Keep on keeping on, you have a winner!
Cheerz!
~Richard

I haven't thought much about the amount of variance in Coti hardness. I guess it the same with most species of stone.
Do harder cotis usually cut faster or do they just normally provide a finer edge?

Another non coticule user with an idea. I use hard slates and slurry on most of my naturals. The more water you put on the hone, the harder it is to make slurry. I makes a very tiny puddle and then wet the slurry stone only a tiny bit and then work it in a dry area and get it started. Once you get a little slurry it help to make more slurry. I also rarely make heavy or thick slurry. Add water in very slowly as you build the slurry.

Originally Posted by JP5

I haven't thought much about the amount of variance in Coti hardness. I guess it the same with most species of stone.
Do harder cotis usually cut faster or do they just normally provide a finer edge?

In my opinion, the harder stones, by themselves, cut slower as the surface is hard and prevents much grit from being exposed or loosened from the matrix.
JMO, YMMV
~Richard

You could also try what I believ is called the "smashed slurry" method. Basically make a slurry with both stones dry, I've gotten my best results with slurries that way. Just be sure to add water slowly, so you don't wash it all off.

But from your results, it doesn't appear that you need a slurry...