Norton waterstones and dmt stones to Japanese waterstones.

[yepimonfire]

So I've done a bit of research and discovered the grit rating on nortons waterstone goes by micro mesh, not JIS like most water stones, so I'm creating a conversion table. Dmt stones also follow MM. I found this important because I was looking to replace some of my nortons as they wore down with naniwas, which go by JIS.

220 MM is closest to JIS 280
1000MM is very close to 1000 JIS. I couldn't find an exact micron conversion, however a 1200 JIS is only 1 micron larger, and 1500 JIS is two microns smaller. So somewhere between there.

The 4000 and 8000 grits is where it gets way off.

4000MM is more equivalent to 2300JIS
8000MM is exactly equivalent to 4000JIS, so if you go replacing a worn down norton with a naniwa or any other waterstone, keep this in mind. Below 1000 grit it's not a big difference. Higher grits are approximately halved in JIS.

 

[eKretz]

Umm. Check the stickies.

 

[Jason B.]

Only if it was that easy.

 

[eKretz]

The sticky grit chart is about as good as you're going to get. After that, you're stuck with the wonky manufacturers and their selective adherence to the numbers. From there, the numbers don't always give a direct reference to the quality of finish you'll get either.

 

[Allen R.]

Only if it was that easy.

This ^ , you haft to also factor in the type of abrasive used ,for example a 4k king waterstone will start to polish an edge where a 4k shapton won't give you a hazy mirror edge. Same with diamonds my 8k dmt will not give the same level of polish as an 8k waterstone. I could write a book With this post but just refer to the Jason's post.

 

[Rey HRH]

This ^ , you haft to also factor in the type of abrasive used ,for example a 4k king waterstone will start to polish an edge where a 4k shapton won't give you a hazy mirror edge. Same with diamonds my 8k dmt will not give the same level of polish as an 8k waterstone. I could write a book With this post but just refer to the Jason's post.

I guess I'm only starting to understand this. I've looked at the grand unified grit sticky.

I only see Shapton on the chart and not King. Are you saying that if there was a column for King waterstones, the 4k King would also be on the same row are the 4k Shapton to denote that both have the same micron size but the actual results will be different? So for the same grit size, the results will be different for different types of material e.g. ceramic versus diamond plate?

 

[Jason B.]

I guess I'm only starting to understand this. I've looked at the grand unified grit sticky.

I only see Shapton on the chart and not King. Are you saying that if there was a column for King waterstones, the 4k King would also be on the same row are the 4k Shapton to denote that both have the same micron size but the actual results will be different? So for the same grit size, the results will be different for different types of material e.g. ceramic versus diamond plate?

Yep, and that's only scratching the surface (no pun intended)

 

[Obsessed with Edges]

I guess I'm only starting to understand this. I've looked at the grand unified grit sticky.

I only see Shapton on the chart and not King. Are you saying that if there was a column for King waterstones, the 4k King would also be on the same row are the 4k Shapton to denote that both have the same micron size but the actual results will be different? So for the same grit size, the results will be different for different types of material e.g. ceramic versus diamond plate?

This will be the case anytime abrasives of different type are compared. Natural abrasives are less hard than most synthetics (like alumina/ceramics, or silicon carbide), and diamond will be harder than any of them. All other factors being equal (including grit size), harder grit will cut deeper and leave a coarser finish. Not to mention, the particular shape of the abrasive particles (jagged & sharp, versus rounder or blocky) will sometimes drastically alter how aggressively they cut. AND, another factor called 'friability' (tendency for a particle to break down in use, to smaller size) will introduce it's own set of complications, as it'll deliver a finer finish as the grit breaks down, after first cutting much more aggressively with a coarser finish.

With just aluminum oxide and ceramics alone (used in making many synthetic waterstones, for example), there are likely hundreds or more variations in the type/shape/hardness of the grit going into making the stones, and each one can be engineered for specific shape, hardness and friability, depending on the desired performance objectives. Different binder materials holding the grit together will also affect how easily a stone sheds or holds it's grit, and that in turn will affect how aggressively it works, for a given grit. Stones that shed grit easily will continually expose fresh grit, which keeps them cutting more aggressively. A stone which doesn't shed it's grit easily in use will eventually slow down as the grit at the surface begins to wear down, losing it's sharp cutting edges (which makes it cut less deep, therefore leaving an effectively 'finer' finish than when new).


David

 

[Llasi]

This may help.

 

[Allen R.]

This will be the case anytime abrasives of different type are compared. Natural abrasives are less hard than most synthetics (like alumina/ceramics, or silicon carbide), and diamond will be harder than any of them. All other factors being equal (including grit size), harder grit will cut deeper and leave a coarser finish. Not to mention, the particular shape of the abrasive particles (jagged & sharp, versus rounder or blocky) will sometimes drastically alter how aggressively they cut. AND, another factor called 'friability' (tendency for a particle to break down in use, to smaller size) will introduce it's own set of complications, as it'll deliver a finer finish as the grit breaks down, after first cutting much more aggressively with a coarser finish.

With just aluminum oxide and ceramics alone (used in making many synthetic waterstones, for example), there are likely hundreds or more variations in the type/shape/hardness of the grit going into making the stones, and each one can be engineered for specific shape, hardness and friability, depending on the desired performance objectives. Different binder materials holding the grit together will also affect how easily a stone sheds or holds it's grit, and that in turn will affect how aggressively it works, for a given grit. Stones that shed grit easily will continually expose fresh grit, which keeps them cutting more aggressively. A stone which doesn't shed it's grit easily in use will eventually slow down as the grit at the surface begins to wear down, losing it's sharp cutting edges (which makes it cut less deep, therefore leaving an effectively 'finer' finish than when new).


David

That's the first page in chapter 1 lol, Also the reason stones are of different price and quality depends on type of abrasive used and binders. A king stone for example while a good stone IMO is at the bottom of the barrel it is a soft stone that wears quickly (more binder less abrasive), while a shapton is a very hard stone and wears slower. Another reason a king 4k will polish and a shapton wont is the king 4k will load up and polish instead of cut where as a shapton will just keep cuttING and you won't get the polish. Some stones like the naniwa 2k green brick of joy claim to be able to give a 5k polish, because the stone wears and clogs so quickly that if you know what your doing you can use this to get a much higher polish than the rated grit of a stone. In fact a lot of stones are like this you just haft to know what your working with and what your doing.

 

[Rey HRH]

Another reason a king 4k will polish and a shapton wont is the king 4k will load up and polish instead of cut where as a shapton will just keep cuttING and you won't get the polish. Some stones like the naniwa 2k green brick of joy claim to be able to give a 5k polish, because the stone wears and clogs so quickly that if you know what your doing you can use this to get a much higher polish than the rated grit of a stone. In fact a lot of stones are like this you just haft to know what your working with and what your doing.

So if you wanted to create a road map for the ultimate polishing in freehand stones, which stones and grits in successive order would you list? And I would assume one can get off the road at any time when they reached their target finish.

Let me be more self-serving with my question: Say you start with DMT Diasharp diamond stones, at what grit do you stop and switch to a different type? Would you switch to Shapton stones and at what grit or do you go to a different kind of stone?

 

[Allen R.]

My finishing stone is always a lapped spyderco UF benchstone, no matter the steel, I usually stick with my dmts from xxc to eef but it really depends on the knife. IMO and from my expierence the UF stone is the finest finishing stone I have for the money. How I get their depends on my mood and time. I have a ton of waterstones from king , naniwa ,bester,shapton,and norton, ranging from 220-12,000, but it's still hard to beat the dmts and spyderco for time.

 

[Kentucky]

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