Had to try a J Nat, did I buy the wrong one?

The Shapton 12k is fine but I'd recommend going further. I'm getting a lot of customers giving me glowing feedback about edges finished to 16k glass backed Shapton. 30k is what I hone out to for folks but a lot of people stop at 16k due to the cost of the 30k. What color would you paint a violin? I mean, if you were to paint one.

 

I am interested in getting a finer stone but the prices seem to increase exponentially, that is another reason I picked up a moderately priced J Nat. My next purchase will be a higher grit synthetic.

For the violin I was thinking pink would look good or maybe a paint that glows under black lights. Mozart played under black lights sounds good to me. I will run it by my gf and she what she thinks. I thinks she removed the really old violins that need painting... I will have to search again.

 

neon green sounds good. With neon pink tiger stripes. Blacklight reactive too.

 

I like it, if she does not like I can just paint over it.

 

What leads you to believe the stone you have is not fine enough. Most will prefer a well finished Jnat edge to that of a synth regardless of the grit. And when discussing Jnats or any natural stone, grit is meaningless. Also more expensive Jnats are priced by size, color and predicted efficacy. Fantastic stones can be found for under $100 because they are small, irregular, or the seller has no idea what he has. Given equal fineness, I would value a softer stone that has greater density of cutting particles than one that is harder but has fewer cutting particles. That would not be the norm. Folks usually pay more for harder stones. Knowing grit density is the toughest part to know.

The point is, you need to learn the stone you have. It may well be fantastic. In the mean time a few trailing edge strokes followed stropping on aluminum oxide to create a micro-convex can help you add a little keenness.

 

I have no idea if it is fine enough, I think it is. I bought it out of curiosity and to learn on a cheaper (smaller) stone. I want to try a finer grit synthetic stone, in order to compare it to the J Nat and what I already use. This next purchase is well into the future, I am going to concentrate on what I have.

Thank you for all the advice and comments. Since I am new to this it is a big help.

 

An amateur/beginner honer that maybe honed 5 razors on less stones with access to an SEM does not instill a get amount of confidence in his findings for me..

or

Magnified pics at a gazillion power honed by a rank beginner means little to me

Huge Grain of Salt to be sprinkled

 

I for one would listen to a PH.D. of physics trained in strict scientific principles with access to a scanning electron microscope rather than someone speculating on anecdotal evidence.

 

and I would not listen to anyone that never honed a razor before he posted his findings..
Sorry but those are the facts of most of his pics, saying he has a PHD is irrelevant unless it is in honing, and his lack of hands on experience means you are basing his findings on a rank amateur with SR's and Stones...
Now if he actually is a Physics PHD and wants to talk about String Theory or something in his field of expertise I might listen, but SR's nope sorry not interested in his findings until he proves he can hone first

edit:
If he wanted to do a real study he had access to a few experienced Canadian honers to help him, but he did not use them He posted his amateur findings and many people never bothered to even question his lack of experience and fell for the allure of pretty pics very disappointing for our community

 

The question was, do jnat particles break down. Something speculated about but never properly tested. He did just that. Just because we don't like an answer does not mean we should impugn the messenger. By the way, metallurgy and material science fall under the domain of physics.

 

I beg to differ. He proved his one stone used with newbie hands while honing did not break down the grit... ie he had no clue what he was doing. His results are invalid due to zero peer review.. I believe that is really the Scientific Process which he declined to even consider

 

How hard is it to create a slurry and examine the particle. Then rub steel on those particles and examine again. That certainly does not require 5 years of honing experience. Which peers are you referring to that he declined? His pics on micro-bevels are fantastic. Also the pics of the edge folding when killed on glass. I had always assumed it flattened out, I was wrong.

 

Yes you have mentioned the PHD several times, again irrelevant in this discussion..
Again if you chose to believe unfounded results from him that is your choice

IIRC @mainaman had some lengthily discussions on this with Todd in the past maybe he has more to input for you on the J-nat subject

 

I do not see a shred of evidence that support his claims. The guy takes pretty pics of stuff but that does not make him necessarily right about his claims? To prove what he claims he has to be able to measure the thickness of the slurry particles, they are flat and layered like pastry. Keeping in mind that the structure of any finishing J-Natt is layered, it is most logical to assume that the slurry particles will break down predominantly by shearing along the seams. Next step would be to do statistical analysis and count how many particles are there with different thicknesses. Then depending on the results there will be evidence for or against slurry breakdown. Obviously this kind of experiment has to be controlled very tightly for the results to be meaningful. What is even more damning is the fact that an SEM cannot take images of the sides of individual particles in any medium, the nature of the experiment does not allow for good control.

Pretty pictures of J-Nat slurry and edges have been taken before the fellow in question started his Ph.D, so it is not like people have not tried to see what is going on. If anyone is interested in scientific discussion of the nature of sharp take a look at that article
https://www.wickededgeusa.com/wp-content/uploads/2012/10/knifeshexps.pdf

Here some pics of J-Nat slurry, taken years before the site in discussion existed. Some of the pics were produced for the book issued by the Kyoto Stone Association, some were taken by a fellow with a PhD in Physics.

http://www.japanesenaturalstones.com/jns-grit-fines-and-hardnes/

We do not know if the slurry breaks down or not, no solid proof either way. We, however, know that in Japan is it a common knowledge that J-Nat slurry breaks down. I am willing to give those folks the benefit of the doubt on the subject, they have been around those hones for close to a thousand years after all.

Finally I can't understand arguments where someone's degree is stated as an argument that that person must be correct this is a logical fallacy.

 

If we could assist the OP on learning how to use his new stone, this would be of great benefit to both him and the TSD community.
I realize that differing opinions exist on certain honing processes but lets try and keep our focus on Keith's j-nat and not let the discussion get derailed onto other potential points of contention.

 

... and back to my J Nat. I will try it again this weekend. I bought some cheap SR to practice honing. I will try to one on the J Nat and the other on my synthetic stones. I will report back.

 

The way this industry works, especially for the man made stones, is that the finer the grit, the more manufacturing and quality control go into the final product. There's also a large amount of expertise. This is why the market is so crowded with lower grit stones. More time, more expertise = more cost.

 

Today I touched up 2 razors on the J Nat and the rest of my razors on the Shapton 12k. I will shave with J Nat touched up razors later this week and report back.

 

So I touched up a Jerry Stark 6/8 on the J Nat and then followed that with some pasted strops, Dovo red/black and then 200,000 grit diamond paste. This time the results was a big improvement over my first attempt. I did more passes on the stone this time.

I do not see the same swarf that I see on my synthetic stones, but I can create a slurry easily with a DMT or the slurry stone. Should I have kept going until I saw the swarf?

 

When I touched up the Jerry Stark I also touched up my first ever razor, a Whipped Dog sight unseen razor. I think it is a 5/8 but it has always been willing to take a nice edge. After the J Nat I used my Dove red/back pasted strop followed with 0.1 diamond paste. I did my normal stroping routine and the shave was the best yet for using the J Nat.