Thread: Grit to mesh to micron conversion

Originally Posted by crazycliff200843

I'm curious as to what one grit would look like. I'm imagining a rock about the size of a baseball. I'm probably way off, though. Or does that even make sense?

If Jimbo's calculations are correct that 1 grit is 14755 microns, then you'd be looking at pieces of rock a little bigger than 9/16" in diameter.

Great information Smokingtbird.

I was wondering where the Chinese 12k ranks on your list, micronwise: according to JIS, on par with Norton or Shapton?

Also, how would the slurry change things for natural stones or waterstones (if there is such a thing as a standard slurry color or consistency you could use to compare) and change their position in the list?

Thanks

Well, that is certainly a good question, but the problem is in the answer....

With man made stones, the company that makes it, uses their proprietary method for sorting grits and they come out with an extremely uniform stone that has "X" size grit according to them..... but the particles they use are made of different materials or are bonded in different ways and can sometimes make for a stone that cuts quicker or slower and finishes rougher or smoother than another company's stone that has the same listed grit or micron size. So in my experience, even 2 stones that are supposed to be the same grit, sometimes finish a little rougher or smoother than each other.

To make matters worse, when you try to classify natural stones it becomes hopeless, because there is no company that is controlling the grit size. The "Chinese 12k" you asked about for example: I have 1 of them and have used 2 others and I would personally classify them ALL as different grits!

The one I have is an extremely fine stone that gives me a better looking and better feeling edge than my Belgian coticule, Norton 8K, or Shapton Pro 12K; although if I flip the stone over (best edge side is a uniform dark charcoal color, and the other side is a hair lighter and has a pearlescent shimmer in bright light) to the prettier side it is a much faster cutter and produces an edge that is a bit more coarse than the coticule.

The lowest grit of the others I tried left a passable edge, but wasn't as smooth as either the coticule or the shapton 12K, and the other one was kind of in the middle though closer to the coticule.


The moral of all this babble, is that every natural stone is different and in some cases different sides of the same stone are different....and I have even heard of people using a natural stone long enough to have the same stone change grit size or cutting characteristics over time.

I for one, like my Chinese hone, and use it regularly for my final edge but I wouldn't be doing that if I had one of the others I have tried. I recommend using what you have if it gives an acceptable edge, and if it doesn't then by all means look for something finer to fill the bill.

I hope I answered your question, even if it wasn't the answer you were hoping for.

Just in case you're interested I would classify my Chinese stone with the dark side at about 14K or so and quite slow cutting and the pretty side at around 8K to 9K but medium to fast cutting. But like I said yours will almost certainly be different.

I completely forgot to reply to your question about slurry and how it changes the stone's cutting ability....

There are more experienced people to answer that question, and here's a link to a thread that talks about using natural stones to go all the way from dull to shaving by just changing the slurry.


From personal experience, I would say that my Chinese hone can go from the cutting ability of my Norton 4K to it's final finishing of around 14K by using thick slurry on the pretty side and thinning it out to water and flipping the stone and doing a lightly milky slurry thinning to water. But I've only done it a couple times as it took me probably 2 hours to do!

This is one of the reasons I stay with SRP, always very informative and with great scientific method and honest inquiry. However, the question I'm going to ask were is the one I know MUST be on the minds of all include pundits of the thread. JIMBO, if you don't mind, what is your general field of expertise?? Anothe way to state is, what'da do 'fer a livin'????

Thanks for all the info fellow's , I really do appreciate it'
much.

tinkersd of SRP.

I know Jimbo's been busy recently, so before he comes with his gormless-twittyish answer I'll say that he normally makes a living out of what follows lies and damn lies

And, of course there's his second job:


I hope this brings him back soon, I shaved today with a razor I have on loan from him, very nice.

Hay, GUGI, got a lot of history there, do ya??

I'm thinking JIMBO's got more brains than most of us, that's all.

I used to hav 'em, but now i'm older and the truth will and did out!!!

tinknersd

Originally Posted by HenrikWL

I don't know if this has been posted before, or even if it's interesting. But I found a conversion chart for grits and microns (and meshes, whatever those are).

Just Ask Jeff: How are grit/mesh/micron related and what is what?

To my understanding, hones are measured in grits, while pastes are measured in microns. This chart helped me see the connection. Maybe it will do someone else some good too.

It's just a nomenclature thing. A 325-mesh sieve in the standard US Sieve Series and Tyler Mesh Series (used in the geo- and material sciences, etc.), for example, will screen out particles larger than ~45 micron. This link lists that same 45 micron size as being '40-50 mesh' (??) and it's 'hone equivalent' as 325-grit. Just a different classification scheme....

Originally Posted by Woodash

It's just a nomenclature thing. A 325-mesh sieve in the standard US Sieve Series and Tyler Mesh Series (used in the geo- and material sciences, etc.), for example, will screen out particles larger than ~45 micron. This link lists that same 45 micron size as being '40-50 mesh' (??) and it's 'hone equivalent' as 325-grit. Just a different classification scheme....

Yes....

And in the world there are multiple classification schemes.

Because there are multiple international standards a Japanese 10K
and an American (US/ISO) 10K hone will differ.

One web site reports"
"15µm Silicon Carbide(SiC) Film - This abrasive is an equivalent of 1200 Grit US,
or 1000 grit in Japanese Whetstone grit classification."

Some makers report the average grain size and others report
the maximum grain size.

For the most part grit finer than 1000 fall off the bottom end
of grit standards and are best thought of as vendor standards
not international standard. This lack of standards for
fine hones confuses some folk.

For this reason it can pay to purchase hones all from
one manufacturer or take a lot of time and research
the topic (or luck).

As others noted the material in the hone is important.
Some vendors transition from one abrasive to another
abrasive compound because in their experience and
their customer feedback guides them to it for specific
grits. CrO, SiO, Al2O3, Diamond, Garnet, Ceramic,
Al2(SiO3)3, boron nitride, numerous carbides etc. all
act a bit differently.

The sponsors of this site often have "sets" of hones.
These value packs make a lot of sense.

hello,
does anyone knows how we can measure the grit size in diamond coated burs