Thread: grit, grade, mesh, micron & finish

Well, there is always the micron rating which is somewhat less ambiguous. There are so many factors that at some point one must rely on actual observed performance rather than manufaturer's hype.

Did you see Bart's thread referenceing an interview with a tech rep from DMT? It discusses some of the things you mention here.
http://straightrazorpalace.com/hones...formation.html

Yeah, I had read that, and it is actually another reason I ask. With the diamonds of the fine embedded about 60-70% of their size is the same true for the EE? If so, the 3 micron diamonds would have about 1 micron exposed. Does that mean they act more like a 1 micron abrasive, about 8k JIS, or is the bonding of waterstones keeping it relatively finer still? Of course, monocrystalline diamond is kinda rectangular & very hard and makes a harsher edge to comparably sized abrasives of many other types anyway.

Also, his comment on controlling pressure applies to any hone that can handle it without being damaged. I do wonder why they don't have a ~12 micron & ~6 micron plate to go between the F & EE. Though I personally am not opposed to going by 1/3 instead of 1/2 for progression, particularly with the speed of diamond.

I have thought about this quite a bit also, and have also read the info from Bart about the DMTs...

With the grit comparison sheet that I cobbled together from info lots of people helped find, I was hoping to clear some of this up....alas is it much more complicated than it looks!

Take the 0.5 micron size diamond for example, people complain about getting a rough shave from diamond that is half that size (0.25 micron), most likely because of it's shape and hardness....if it's CrO, some people have used the 3 micron size and gotten beautiful shaves, probably because the particles are softer and more round.....if it's Cerium Oxide, I believe I read where someone had tried "400 grit" Cerium Oxide and got a decent shave from it, probably because it's so soft and maybe because of it's particle shape (which I don't know), or maybe because it broke down into smaller pieces or something.....

Another example of this was in the thread I first posted the grit comparison in, Glenn compared using a Norton 8K and a Shapton Glass 4K Here ....he didn't say much about it, but I would assume by his reply, that he thought the norton was a smoother edge....

I expect that the Norton 8K gives a smoother edge than the Shapton GS 4K...now whether this is because of the 0.68 micron larger particle size listed by their manufacturers, the binder they each use, the height that each particle protrudes above the binder, the hardness of the abrasive material each uses, the shape of their respective abrasives, or some other factor I never even though of.....who knows....

I would love an answer to these very questions you have asked, but unless someone devotes the rest of their life and an untold fortune in equipment, I don't exactly expect any real answers that we can take as fact.

Well, the DMT EE 8k is comparable to a Naniwa 3k in finish. Other 8k stones seem to be finer than the DMT, but then again the Japanese rating system is different. I don't even know how they come up with the numbers.

Originally Posted by Smokintbird

Another example of this was in the thread I first posted the grit comparison in, Glenn compared using a Norton 8K and a Shapton Glass 4K Here ....he didn't say much about it, but I would assume by his reply, that he thought the norton was a smoother edge....

That post is an excellent example of what is puzzling. On the surface, I can see how it is easily confusing to think one 8K is rougher, beyond acceptable variability, than another 8K. 8K should be 8K. But, 8K what? Is it as confusing to say this 3 is coarser than this 1.84 (now using same scale, microns)? Or, is it more confusing to say this 8K is the same as this F2000 (different scales, same size particles)? Can you shave off of all 8K edges? Is the 8K DMT an acceptable stopping point? If not, is 1 micron diamond lapping film? If you can shave off a 12K, can you shave off a 2K? 2K CAMI is a little finer than 12K Glasstone, and is 1 micron average size like the lapping film.

Obviously, you can't look at just numbers without reference to determine where stones should fit. I personally feel micron rating trumps all other scales because it is more easily understood, and no country, consortium, or company is going to make up their own micron the way a new mesh or grit grading system can be. If the micron changes, it will change for everyone.

Now once you get some idea of particle size, you need to look at the other properties. Well, unless you have HAD, then you just buy them all anyway. Otherwise, all things mus be weighed. If someone said they had a natural Japanese stone that operated over a short range of finishes by creating a slurry or using with plain water, that information alone is as useful as saying you have another stone that is 3K. 3K what?

Oh, and that natural wasn't a Karasu that could provide finishes on the order of 6K to 10K Naniwa, it was an Iyoto that worked more like 500 to 1000. Dang.

edit: I'd also like to throw the ceramics and Arkansas stones out there. Sal Glesser said the different grade ceramics are all the same particle size, but the stones give different finishes. The ultra fine is fine, just surface ground. The medium can eventually wear out, while he says the fine & UF should not. IIRC, Arkansas are similar, the diatoms were all about the same size (3-5 micron), but the different novaculite stones perform based on other factors that determined the density of these little fellers. Stranger still, a hard black or translucent are said by some to create a shaving edge, while no charts I have seen on the web grades them any finer than around 2-4K

Here comes the confusion again????

Guys please don't put words in my mouth I can speak (or type) for myself...

Here is my stance:
You are confusing people to death with the different grit comparisons period end of story...

a Norton 8k you can shave off of
a Shapton GS 8k you can shave off of
a Naniwa SS 8k you can shave off of
a Naniwa Chorsea 10k you can shave off of
a Yellow coticule you can shave off of
a very fine translucent Arkansas you can shave off of
almost all the Japanese natural stones you can shave off of
the Charlney Forest you can shave off of
the BBW Bart proved you can shave off of
a SpyderCo UF you can shave off of
a DMT 8k some people say you can shave off of (I haven't done it)
you can shave off of just about every Barber's hone ever made...

I am quite sure there are more I am missing...

Soooooo that is my stance, when it comes to analyzing your scratch patterns, and trying to put things in order that's great, BUT when it comes to shaving, all the scratch patterns/ grit comparisons in the world don't seem to mean a thing.....

I am sorry that you think I was being negative in all those previous threads, but what I saw was a ton of very mis-leading information that would lead to new people buying way more stones than they need, and actually wrecking their honing by adding un-needed stones, that the charts show should go in sequence....

This of course is JMHO

Originally Posted by gssixgun

Here comes the confusion again????

Guys please don't put words in my mouth I can speak (or type) for myself...

I didn't think you were confused, but your statements would be ones that those with no experience with the stones, but access to the charts, could potentially ask. My basic message to new sharpeners is 'grit doesn't matter'. It does, in a sense, but imo, it's better to start with something stable that can't be confused with another scale - like initial average micron size, and compare micrographs and others' impressions through actual use, if you can't sample the stones themselves. I sometimes see people list their sharpening progression, and they do just as you say, unneeded stones, wasting steps by overlapping abrasive sizes.

Originally Posted by hardheart

Stranger still, a hard black or translucent are said by some to create a shaving edge, while no charts I have seen on the web grades them any finer than around 2-4K

Under the US grit rating, that sounds about right. A translucent Arkansas is quite fine, it's estimated to be 8k JIS grit on our wiki, which agrees with my experience. Used dry, it's more like a ~10k stone (JIS rating).

yeah, but it was a JIS comparison, not CAMI. Very strange.

Someone told me that grit rating was not determined by particle size alone, that other characteristics of the hone were involved. I believe this to be completely false. The Norton and DMT are 8Ks becasue they use the mesh rating and have 3 micron particles. That has nothing to do with the binders, nickel plating, the fact that one uses diamond and the other doesn't, etc. Those 8Ks do not compare, nor do they have to compare, to glasstone, super stone, sigma power, gold stone, cerax, etc.

8 miles does not compare effectively to 8 kilometers. They are different measuring systems, but both measure distance. One is 60% longer than the other, the number '8' is completely irrelevant and denotes no similarity. I believe the same holds true for hones. The manufacturers simply cannot make an 'effective' grit rating. They don't know what you're sharpening, how you're sharpening, and they aren't collaborating to compare their finishes on some baseline material, angle, number of strokes, amount of pressure, etc. What is 'effectively' an 8K edge? One that matches a Kitayama? One that matches a G1 stone? One that matches a D8EE? They all say 8, which 8 is the 'effective' one? Mesh, JIS, something else? I like microns. Microns are microns. Once I know my 1K/4K progression in mesh is 14/6 micron, then I can effectively compare to JIS. Which would not be 1K/4K, because then I would be going 11.5/3 micron. Instead of a little less than half size, I'm progressing down to a little more than a quarter. Then I wonder why my stones seem slow, or the finish doesn't match.

I wish I was better at straight shaving, or had more honing gear so I could do more & better comparisons. I just rehoned my razor with the 4K King, 15 laps with a single layer of tape, no CrO after. I would like to compare this to Norton 8K since the particle size is the same. The shave was not great, but I am not a great shaver. My face is not raw, and I'd say I got about as good as a quick 2 pass with the Mach 3.

this is what meager fare I currently have - 4 diamond plates, 4 diamond cards, 1 diamond steel, 1 Fallkniven DC4, 4 naturals [aoto/kiita/Ch12K/mudstone] 4 Matsunaga King grits, 1 glasstone, 1 Norton water, 3 Norton oil-crystolon & india combos, 5 leather mounted on wood, 2 Spyderco rods, 1 Norton/St Gobain stick, 50 carats 0.25 diamond, small bottle HA 0.5 chromium oxide, small tub HA 3 micron SiC, 0.3 alox lapping film, awaiting 10K super stone

I am going to stop my participation in the old practice of referring to non rated stones by some number that really holds no meaning. Sal Glesser has stated that Spyderco will not provide a grit rating to their sharpeners because they can't. The man founded the company on these tools, not the knives, and he will only go so far as to call them medium, fine, and fine with surface lapping. They all have similar sized abrasive particles, they cannot be assigned a grit. Same with Arkansas stones. The diatoms all fell within a certain size (not the real reason), the abrasive their skeletons became will not differentiate in size from washita to translucent. Specific gravity can work for grading, but there is not grit measurement appropriate. I will not call them 800, 2K, 12K, or otherwise, because that means there would be a 'standard' finish provided at one of those 'standard' grits. There isn't. I asked what grit range a J-nat would fall under, just hoping to get an idea of how coarse to how fine they can go, but I will never be able to say that a kiita or asagi is 31,500 grit, or 43,782 grit.

Originally Posted by matt321

There are so many factors that at some point one must rely on actual observed performance rather than manufaturer's hype.

+1 ... that is all you can do and come to your own conclusion on what works for you IMO.