Jnat after escher.

[Brooksie967]

Fooling around, as we all do, and decided to take a maxed out escher edge to my hardest Jnat, my 5+ Ozuku Mizu Asagi.

At the point where I had finished honing on the yellow/green escher there were very few scratches seen at 60X magnification. Eschers are funny things; they really do leave a gleaming mirrored finish on a bevel which is unlike any other natural I've seen.
2 x shave ready razors were brought to the 1k mark on a chosera 1k. Each razor was put through a coticule dilution progression to a maxed out coticule edge. 40X strokes on escher with creamy slurry and then the bevel was inspected after every 20 x strokes to check when all the coticule scratches were removed. Approx 60 strokes needed per razor to do so.

Then I started on the jnat, clear water only, with 40 X strokes and re-inspected the bevel. Honestly there was no noticeable change.

Another 40 x strokes and the very few shallow scratches that the escher left had been removed and all that was left under 60X mag was a perfectly mirrored bevel. Strop and HHT5 the entire length of the blade.

This was repeated on a second razor with identical steel (a 2 day set of 1800's sheffield steel, one wedge one more hollow ground).

Spine wear was also inspected and results mimicked that of the bevel.

Test shave tomorrow to see what's happened.

Thoughts:

1. This bevel looks completely different than one that's gone through a progression that involved jnat slurry. Typical jnat edges are 'hazy' and there was nothing that suggested haze on these bevels.

2. Test shave may reveal one of two things: situation A would be that I like this edge better. B would be that I like it less. If A is the outcome, I will repeat this on a variety of razors to see if results are similar.

Reasons for this experiment:

1. Recently I've been finding that my face is liking an escher edge over my typical jnat edge.
2. I had nothing better to do today.

 

[Obiwan]

Very interesting. I've usually tried my jnats after a synthetic or a coticule, but never an escher. Cool, keep us posted.

 

[alx gilmore]

Test shave tomorrow to see what's happened.

Thoughts:

1. This bevel looks completely different than one that's gone through a progression that involved jnat slurry. Typical jnat edges are 'hazy' and there was nothing that suggested haze on these bevels.

2. Test shave may reveal one of two things: situation A would be that I like this edge better. B would be that I like it less. If A is the outcome, I will repeat this on a variety of razors to see if results are similar.

Reasons for this experiment:

1. Recently I've been finding that my face is liking an escher edge over my typical jnat edge.
2. I had nothing better to do today.

Brooksie

You are only polishing and burnishing your blade if clear water on a level 5+ stone is what you are talking about. Very little honing is going on at these stages with clear water. Even a medium hard J-nat will leave a bright finish on your blade if the stone is used under running water. It is the slurry or absence of that will leave either a hazy or a polished finish. As simple as that.

Does your Escher leave a hazy finish if you use it with a slurry?
Alx

 

[GreekGuy]

I agree with Alx regarding the cutting ability of a JNat at this stage. If you wanted to use a JNat after an Escher I would suggest a very slight tomo slurry, and diluting it or allowing the slurry to break down further to polish.

I think this is an interesting idea, but I tend to use either an Escher or JNat, not both on the same blade. I'm curious to hear more about your experimentation.

 

[Brooksie967]

Alex, I'm really trying to figure out if this jnat can be used at a water only stage at all.
I find that if i've gone through a full nagura progression even after 50 laps on just water there is still a haze to the edge, this is not so with the escher edge then Jnat.

At the point of escher on water finish under 60x mag there were very few scratches noticeable. I rolled the razor in my hand under direct sunlight and inspected the bevel at every angle as I've noticed under direct light scratches can seem to disappear while viewed at an angle they become apparent again.

Re escher with slurry: There are more scratches on the bevel with slurry but no haze to speak of. I've mentioned previously that the escher is peculiar in the sense that it really does leave a different looking, far more mirrored bevel, than any other natural stone I've tried.

 

[SliceOfLife]

I like that word. Burnishing.

But yeah, using a super hard jnat on water only after another finisher reminds me a lot of going to a trans ark after a finisher or a LWW after my DMT 1.2k. I'm not really introducing a new scratch pattern to the bevel as the cutting is so shallow that I'm only scratching the surface of the negative space left by the scratches (the negative-negative space?). Under a scope, if checked frequently, you don't so much see new scratches (unless you mess with light angle to really look for them) as you see the existing scratches getting thinner and the gaps between them increasing as they get mowed down (decreasing the edges std dev, as I like to think of it).

 

[Steve56]

Have to agree with burnishing. A CW finish on my hard fine Ozuku not only polishes/burnishes the bevel, but the stone too as can be seen with a strong reflection in the hone surface, or with angled light. If the stone is this hard, try a dilute slurry that is so thin you might question if there is any.

Cheers, Steve

 

[Brooksie967]

I've actually worked with this stone for a better part of a year with varying thicknesses of slurry and 4 different tomos after a b t m progression. Nothing has left a bevel this mirrored so far.

 

[SliceOfLife]

Could be a couple different things, but the most probable reason would be that the escher is taking you further than you were getting on tomo slurry before, allowing your work on water to proceed more quickly. Were you noticing significant differences between the finishes off the four tomo's? Was your technique before the Nagura progression the same as your technique before the escher?

 

[alx gilmore]

The only way I have been able to put a very bright mirror finish on a good hard blade using a Jnat was to tape the spine with 2 or more pieces and hone directly under running water. This produced a mirror finish but only just at the very edge after about 50 strokes as seen under my microscope. I have tried to polish a full bevel with running water and it did begin but it was only after hundreds of strokes and it never did get totally bright. Just too much surface area to deal with.

I have noticed as Ian states if I am not mistaken, that the brightness begins to develop as the high points of the scratch pattern begin to shallow and flatten out rather than any new and finer scratches replace the coarser or varied previous scratches. This leads me to believe more in the burnishing effect where the stone loads with swarf filling up the voids so at some point less metal removal is happening while a burnishing effect takes over.

There is still some room here however in my mind that some cutting at a super fine level is happening but only up to a point. I have collected dried slurry after lapping millimeters off several stones and went to a plate glass lapping surface with it. With a flat fresh glass surface and a totally bright blade honed on my 30,000 Shapton I went at it with the dried awase powder that was abraded from the stone with a #600 Atoma. I found that with the first few passes on the glass a few shallow scratches were left on the blade, but after 5 to 8 passes no more fresh scratches appeared and very little visible abrading action was occurring. I can only suggest that 1)the cutting action continued but at a microscopic level beyond my lenses resolution, 2)the abrading action halted.

The next step I roughened up the glass with carborundum paper and applied the dried slurry. This only 1)extended the life of the abrasion period by providing some small amount of fresh particles drawn up from the valleys of the scratched glass, 2)and or the glass provided some form of scratches themselves.

So much of this is guess work with me and speculation.

sorry for any confusion,

Alx

 

[Steve56]

I'd agree with Alex. When I sharpen or lap, I wipe the slurry up with lint free towels and use them to polish. Hakkas and suitas are known for their "kasumi" or hazy finish they impart, yet slurry on a paper towel only polishes, even from a stone as coarse as about 2k equivalent Japanese natural.

it would be wonderful if you could produce a kasumi finish with only slurry, but you cannot.

Cheers, Steve

 

[Brooksie967]

Very interesting stuff guys and it's all noted.

As far as the different tomos used, every time I finish with one there is a haze left over, some a darker haze, some brighter and more 'mirrored' but still hazy.

The only way I've been able to achieve this is escher right to the jnat which happened randomly as I was just fooling around to see what would happen.

As far as scratches go, I can't see any at the 60X mag, i'm sure there are still there and the optics of this loupe are questionable as it was dirt cheap, but it's still a very bright polished mirror that lacks any remnants of haze.

I've now done 4 blades this way, test shave in the morning.

 

[Gamma]

I like the word burnishing also.
I've often said, and once I got into a big arguement over this, that finishing on an Ark is more like polishing/burnishing than it is like cutting.
I do feel that one of my Nakayama has a similar 'feel' to an Ark in some ways - but sensations are often subjective concerns I suppose. Water-only laps on that stone requires a black belt in Ninja science so the even thinking about attempting that is a rare event
I've jumped from Eschers of all flavors to Jnats of all flavors. I happen to like Escher edges so it seemed like a natural almost mathematical event.
Thing is - I get mirrored bevels and hazy bevels regularly - I don't really pay much attention anymore to be honest.
Mostly - it seems to depend on my finish technique on the Jnat. So I wouldn't be able so say one way or another if the Escher had anything to do with the bevel's visual appearance.
On their own - Dark blue Eschers seem to have left brighter bevels than the greenish ones - at least for me.

One thing I do believe though, and it seems to fit into this thread's story line - is that changes in particle sizes and shapes (from stone to stone) has a tremendous effect on edge refinement and bevel polish. I don't mean so much in a 'grit' sense here, although that has to be part of the story by default - I'm talking more about how the abrasives work on the steel.
But that's my own private Idaho... one that keeps me awake at night sometimes.

Whether or not there's a metric to track any of it, or even if trying to figure it out is imporant in any way - I have no idea.
But it's fun so who cares?

 

[SliceOfLife]

Greens tend to be softer and Dark blues tend to be harder... but the hardest thuri I've ever owned was a y/g, and I've had a half dozen or better soft DB's, so it's not an absolute rule. Still, in general the greens kick up more autoslurry in use than DB's, so that'd explain the blues giving a better mirror on the bevel.

I went Escher/thuri to Jnat for a good year or two as my favorite finish, until I picked up a Mejiro Nagura to replace the Escher level honing. Won't say that the final edge is necessarily any better than before, nor can I really comment on how the bevel look changed under magnification, it's just a matter of convenience. Going DMT's to Jnat is a bit easier than DMT's to Thuri to Jnat. For a brief time I went Escher to Jnat on water (until I found a tomo I liked), but my edges were much improved once I added a tomo into the mix. As I indicated above, that progression didn't really do anything for me that Escher to Ark couldn't do.

 

[Kentos]

I must say you gentlemen have taken honing to another level! Very interesting stuff.

 

[Brooksie967]

Well the shave this morning was pleasant! A definite increase in keeness over a regular escher edge but some of the smoothness was gone.

Will try one of the other razors (did 4 total last night) to see how different steel reacted. It's my feeling that sheffield steel is softer than say new dovo steel and the dovo is what I used this morning.

 

[Brooksie967]

So I've been dabbling with this for a few days now and I'm finding that the finishing on water is corresponding with a regular nagura progression. Incredibly keen edges are being produced but they are lacking smoothness.

I've actually been dabbling with finishing on an escher after maxing out my jnat edge and have been more pleased with these results.