Grit standards?

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Ryansknives

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Nov 9, 2019
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So is their a standard for Grit when it comes to abrasives or is the standard all set by the manufacturer? I received a King KW65 today. I’ve never used Japanese water stones. Just run of the mill junk and the Edge Pro stones. Their is a huge difference between the Edge Pro stones and the King. The edge Pro 1k stone is way way harder and leaves a more vibrant finish than the King 1k stone. I think it would take me 3 days to sharpen a knife with the Edge Pro 1k. Well probably not that long but no comparison. So is their a standard and are they tested or is it up to the manufacturer to rate the grit?
 
There are permanent threads just above the list of changing threads in the slightly yellow colored area of this section of Blade Forums. They are called "stickies".
Here is a link in any case click on this :)
 
Ryansknives said:
The edge Pro 1k stone is way way harder and leaves a more vibrant finish than the King 1k stone. I think it would take me 3 days to sharpen a knife with the Edge Pro 1k
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Yes I know what you mean.
Still though the King 1K or was it 1200 was my first real sharpening stone back in the eighties. It was not coarse enough either to sharpen many of the dull edges I encountered on.

You may want to invest in some coarser stones for the Edge Pro. At least down to 220. I have stones for the Edge Pro down to 60. Check out Gritomatic for a source and also check out some of the extra coarse diamond stones for the Edge Pro.

In general the Shapton Glass stones tend to sharpen finer than the numbers might lead one to believe. For instance for my usual finish stone for a free hand bench stone is generally speaking an 8,000 and produces the polished but useful edge I like. But with the Shapton Glass stones 4,000 is very similar (more like 6,000) and is a satisfying stone for me to end with.

Usually though to begin to sharpen a significantly dulled edge I drop back to Shapton Glass 220 and for reprofiling or correcting the angles of a factory edge I go down to the 60 grit etc.
 
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There are a number of different grit grading standards. The King stones would be using the Japanese JIS system, while the Edge Pro 1000 is graded in the FEPA F scale. There is quite a lot more to this, as within each specific grade there is room for considerable variance, and even if particle size distributions were exactly the same stones could perform very differently due to differences in abrasive type, particle shape, bond type, porosity, fillers, lubricants, etc. Despite these substantial factors that are not expressed in single number I believe there is still value in knowing the approximate median particle sizes of various grit ratings, and I have expended considerable effort in producing a compact reference that I call the Grand Logarithmic Grit Chart (GLGC) in recognition of the Grand Unified Grit Chart that inspired my effort. That chart can be found at http://myplace.frontier.com/~mr.wizard/GLGC/ — please see the README.txt file for explanation, and please respect the license therein.

I also recommend reading https://uama.org/abrasives-101/

Gritomatic Gritomatic is the English version of https://www.ru-chef.ru/blogs/articles/Зернистость-с-чем-ее-едят up yet? That would be a good response to this.
 
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Ryansknives said:
So is their a standard for Grit when it comes to abrasives or is the standard all set by the manufacturer? I received a King KW65 today. I’ve never used Japanese water stones. Just run of the mill junk and the Edge Pro stones. Their is a huge difference between the Edge Pro stones and the King. The edge Pro 1k stone is way way harder and leaves a more vibrant finish than the King 1k stone. I think it would take me 3 days to sharpen a knife with the Edge Pro 1k. Well probably not that long but no comparison. So is their a standard and are they tested or is it up to the manufacturer to rate the grit?
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This is the thread Wowbagger Wowbagger was referring to.

https://www.bladeforums.com/threads/the-grand-unified-grit-chart.856708/
 
The major grit standards you'll encounter are ANSI (American), FEPA F (European), JIS (Japanese) and µm (microns), which is the most universal measure since it's an actual measure of the diameter of the grains. The different grit standards (other than µm) are very close to equivalent to one another at the very coarse end of the spectrum, but diverge pretty rapidly from one another as you enter the higher grit ranges. Natural stones do not have a grit rating, despite what you'll sometimes see listed, and these are made up numbers extrapolated from the kind of finish the company expects from graded stones in that grit range. There is not industrial standard for grits higher than 8,000 JIS, so if you see higher ratings than that (which one often does) then this is also an extrapolated number. Furthermore, bear in mind that abrasive papers, diamond plates, and other coated abrasives usually have a different grit rating system than bonded abrasives, and there are many other variables that affect the actual surface finish and edge produced from a given stone.
 
Water stones are usually on the JIS, though this varies. Shapton is a bit coarser.
India stones, SiC and Diamond stones are normally FEPA F.
Gritomatic uses the Russian scale, can't remember the name. Though in they've been labeling in FEPA F this past year.
Diamond spray and CBN for stropping is normally in mircrons.
There is a conversion chart floating around the internet.

You can go by general range - ie set a bevel with a coarse water stone (say 320 JIS), use a medium diamond stone, and finish with black novaculite (roughly 1000-1200 FEPA F). Different scales, but it functionally works.
 
O Ourorboros If you email me at wadenorton2008@yahoo.ca I can email you a very easy to use pdf chart just title the email pdy grit chart.

I find that opposite it's mainly the Boride Venev and a few others that are listed in FEPA F but I know what you mean it's hard without a a chart.

The other grit rating system your thinking of is called Micro Mesh I think but I could be wrong,if it's the one I'm thinking of it's mainly for diamond paste and emulsion's.

If you see a diamond paste and it say's 5/3 what it's means is that it's a 5 micron paste and there can be 3 micron particles at the smallest size that slipped threw during the filtering process.
Also it should be noted that there will be between 97 and 98% 5 micron particles in the mix and between 2 and 3% 3 micron,the target is for there to only be 2% 3 micron particles in the mix.
 
wade7575 said:
O Ourorboros
I find that opposite it's mainly the Boride Venev and a few others that are listed in FEPA F but I know what you mean it's hard without a a chart.

The other grit rating system your thinking of is called Micro Mesh I think but I could be wrong,if it's the one I'm thinking of it's mainly for diamond paste and emulsion's..
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Thank's for explaining the 5/3 thing.
I'm sure my Venev OCB stones have FEPA-F as well as the Russian system. My Venev SiC water stones are labeled in JIS.
Yes, I forgot that diamond stones also use the Mesh system.
I don't know if this is how the Edge Pros are labeled, I was talking about the benchstones.
Really at this point I know how my stones finish and pick based on that and the steel they can handle.
 
wade7575 said:
The other grit rating system your thinking of is called Micro Mesh I think but I could be wrong,if it's the one I'm thinking of it's mainly for diamond paste and emulsion's.
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Micro-Mesh® is a registered trademark for cushioned abrasive from Micro-Surface Finishing Products, Inc. I am not aware of use of that phrase elsewhere in abrasive terminology, but it is a natural combination so it wouldn't surprise me. If you find that it is please let me know.

wade7575 said:
If you see a diamond paste and it say's 5/3 what it's means is that it's a 5 micron paste and there can be 3 micron particles at the smallest size that slipped threw during the filtering process.
Also it should be noted that there will be between 97 and 98% 5 micron particles in the mix and between 2 and 3% 3 micron,the target is for there to only be 2% 3 micron particles in the mix.
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That does not match the information provided on https://www.ru-chef.ru/blogs/articles/Зернистость-с-чем-ее-едят According to my reading of that the GOST 9206-80 grade 5/3 can have oversize particles as large as 7 microns, up to 5% can be over 5 microns, and up to 5% less than 2 microns. If I may, what is your source for this?

Ourorboros said:
I don't know if this is how the Edge Pros are labeled, I was talking about the benchstones.
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The original Edge Pro silicon carbide and alumina stones use the European FEPA F grade.
 
In that article only 7/5 was mentioned that I could see not 5/3.

Also I didn't read the whole thing and that looks like that maybe for powders fr sharpening stones but I can not say.
I was told what I said by Konstantin of Gritomatic and a guy from the Ukraine who owns his own company and sells Diamond Paste's and Emulsions and other diamond products and they both told me the same thing I stated above.

The reason I'm guessing that article is for powder for sharpening stones is because if you had to filter that much power to that strict of a tolerance I mentioned it would be very time consuming.

It is possible I misunderstood what I was told by Konstantin and the Diamond paste guy but how I said it was how it was told to me.
 
Gritomatic said:
https://www.gritomatic.com/pages/grit-fundamentals
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Very nicely put together. I like to say that "anything becomes complicated when examined closely enough" and it's fully true when it comes to abrasives. Most people just look at grits of unlabeled classification and think "a higher number means it'll produce a finer result" when that's not always inherently the case, due to how it compares to other grit ratings and formulations. Understanding what grit ratings actually mean is a solid step towards de-mystifying that false perception. :thumbsup:
 
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