Thread: Coti bout standard and select differences?

Originally Posted by Sebrazor

Wowza, very interesting. Sound like a real challange with this one.
I have a very hard vintage La Veinette that was very rough after lapping with 1.2k wet/dry and the result was bad.
Even hard slurrystones brought no improvement. I purchased some 2k wet/dry and it was a little better. After many hundred laps with a razor it is quite smooth now and very fine.
I have an other even harder stone that was very different. After the 0.8k wet/dry it was like glass. No honing effect, no edge improvement, a dead stone with or without slurry. I lapped this one with a coarse diamond plate (about 300grit) and smoothed it with a hard slurrystone. Then it was a fast stone with slurry and a good polisher.
It needs many tiny hollow spaces under the blade, scratches so to speak. It was like an LesLat from the hardness but there was a creamy or oily honing feeling when lapped with 0.8k or higher. Really like an oiled glass plate, very strange.
How behaves your stone while honing? Is there a smooth or a coarse sharpening feeling?
Sorry, what is a PHIG?

PHIG - People's Hone of Indeterminate Grit. Typically marketed as a Chinese 12K or a Guangxi hone. This stone is very hard, rather slow, but also makes a fine finish. I like using it to test how fast a stone will make a slurry because it is so hard that typically none of the mud created will contain pieces of the PHIG.

How my coticule behaves really depends on pressure, and honing media. If I use any amount of pressure it feels quite coarse. The same can be said for shave lather and pure oil. It's almost like those 2 create a suction that pulls the blade to the hone, and make it cut as though some level of pressure was being applied to the blade. Water is a little less coarse, but the shave was still quite bad. And of course with pressure the stone feels coarse, I would say it's like running the blade over wet/dry sand paper.

But with oil that is cut with spirits to thin it, the blade does not stick and it feels much smoother provided that absolutely no pressure is added to the razor. And of course, this is after lapping, polishing, and thoroughly burnishing the surface of the stone.

I have to say that, of all of the stones I have read about and experimented with, coticules seem to have the most character. I read about stones like yours that seem dead when only polished to 800 grit and it simply amazes me. Every last one of my natural stones requires a fairly good polish to be a good razor stone. 800 grit simply will not do, yet this is too much for your coticule. As you say, very strange.

Then you have a vintage La Veinette that seems similar to my stone - it would not perform until polished to 2K grit and burnished with a razor for several hundred laps. And there is mine, which had to go 2 steps further - Chromium Oxide polishing with a buffing wheel after thousands of laps with a razor, and use of a thin honing oil as opposed to water. Now it can behave like a razor finishing stone.

Someone told me once that there is not as much variance as I seem to think from one coticule to the next. But I have held in my hands a very hard coticule rubbing stone that was as difficult as any other stone I own to create a slurry with. I currently have 2 rubbing stones that are much softer and can create a milky slurry in 20-30 passes across any stone I have. And I have also owned at one point a stone that almost seemed to melt, and would be milky in 10 passes or fewer. If these small bout 1-2 rubbing stones can show such variance, I can only imagine the difference from one hone sized stone to the next.

Which by no means makes them 'bad,' but it does make me quite glad that I began learning with other hones and had more time to study and learn before obtaining a coticule. If I had gotten one of these earlier on, I would perhaps have spent months or longer trying to figure out the right formula to get a good edge, or possibly have given up entirely and sold/traded it off. Even though this did put up quite a fight, I've only spent a handful of days getting it calibrated and zeroing in on a method that works.

Thank you very much for the information. Yes, I would say there are bad stones for razors among Coticules. But I do not think that such problematic stones are sold as selected, though, I had one selected with hard invisible inclusions which caused chips on the edge. But the seller sent me a new and everything was ok. With Jnats it seems to be easier, a Nakayama Asagi hardness 5+ seems always to be a good razor hone. I have a couple of softer Cotis that outperform many of my hardest ones. When honing whith the weight of the blade they can produce a mirror polish without self slurrying. Some are super easy to use and can sharpen a razor from a King 1k to shaveready in two or three minutes. I think the variety is what I like the most among Cotis, even if the one or another specimen can be frustrating.

Originally Posted by Marshal

PHIG - People's Hone of Indeterminate Grit. Typically marketed as a Chinese 12K or a Guangxi hone. This stone is very hard, rather slow, but also makes a fine finish. I like using it to test how fast a stone will make a slurry because it is so hard that typically none of the mud created will contain pieces of the PHIG.

How my coticule behaves really depends on pressure, and honing media. If I use any amount of pressure it feels quite coarse. The same can be said for shave lather and pure oil. It's almost like those 2 create a suction that pulls the blade to the hone, and make it cut as though some level of pressure was being applied to the blade. Water is a little less coarse, but the shave was still quite bad. And of course with pressure the stone feels coarse, I would say it's like running the blade over wet/dry sand paper.

But with oil that is cut with spirits to thin it, the blade does not stick and it feels much smoother provided that absolutely no pressure is added to the razor. And of course, this is after lapping, polishing, and thoroughly burnishing the surface of the stone.

I have to say that, of all of the stones I have read about and experimented with, coticules seem to have the most character. I read about stones like yours that seem dead when only polished to 800 grit and it simply amazes me. Every last one of my natural stones requires a fairly good polish to be a good razor stone. 800 grit simply will not do, yet this is too much for your coticule. As you say, very strange.

Then you have a vintage La Veinette that seems similar to my stone - it would not perform until polished to 2K grit and burnished with a razor for several hundred laps. And there is mine, which had to go 2 steps further - Chromium Oxide polishing with a buffing wheel after thousands of laps with a razor, and use of a thin honing oil as opposed to water. Now it can behave like a razor finishing stone.

Someone told me once that there is not as much variance as I seem to think from one coticule to the next. But I have held in my hands a very hard coticule rubbing stone that was as difficult as any other stone I own to create a slurry with. I currently have 2 rubbing stones that are much softer and can create a milky slurry in 20-30 passes across any stone I have. And I have also owned at one point a stone that almost seemed to melt, and would be milky in 10 passes or fewer. If these small bout 1-2 rubbing stones can show such variance, I can only imagine the difference from one hone sized stone to the next.

Which by no means makes them 'bad,' but it does make me quite glad that I began learning with other hones and had more time to study and learn before obtaining a coticule. If I had gotten one of these earlier on, I would perhaps have spent months or longer trying to figure out the right formula to get a good edge, or possibly have given up entirely and sold/traded it off. Even though this did put up quite a fight, I've only spent a handful of days getting it calibrated and zeroing in on a method that works.

i've only honed on coticules, nothing else. i learned how to hone on coticules, nothing else. While they do have individual personalities and take some figuring out, figuring them out is still pretty simple and straight forward.