Shapton HC (High Carbon)

[Andrew Pitonyak]

Has anyone used the Shapton HC (High Carbon) stones? Can anyone clarify the difference between HC and not HC?

You can find these on both the Glass and the Pro stones. The best that I could find is that you should get the HC if you find the "not HC" version to be unsatisfactory with your high carbon knives.

My best guess is that there are (I believe with almost no conviction) that there are High Carbon Japanese knives that are very hard (and I think have very small particles). I guessed (also with no certainty) that the HC stones might be slightly reformulated to work with harder steel.

So I am curious if a person who does not have a stone and would it make any difference if they purchased the HC version even if they did not need it.

I did find at least one mention on the site here, but that was years ago with nothing concrete stated.

I do own one knife with particularly hard steel and I own PM-V11.

[David Bassett]

Sharpening Supplies says they generally recommend HR, that it is designed for more complicated steels, e.g. stainless. They say HC is best for hard high carbon steels, e.g. razors, and recommend it if HR isn't providing the quality edge you need with them.

Chef's Knives To Go sorta' says the same, but says they don't see any significant differences in practice.

You can judge for your needs, but I read it to say probably no advantage, but if you need quarantine entertainment it might be worth an experiment. (YMMV!!!)

[John Lanciani]

I wonder if, much like the Sigma select II line, they are softer and more friable to deal with harder steeels.

[David Bassett]

I wonder if, much like the Sigma select II line, they are softer and more friable to deal with harder steeels.

I didn't read it that way, but perhaps. Both sources emphasized high-hardness low-alloy HCS, e.g. Hitachi White steel, for the HC stones. The friable Sigma Select II stones are held up as the standard for the carbides in the high-alloy "super" steels (M4, M42, D2, CPM-10V, A-11? and etc for all the whizzy steels I'm forgetting.) I remember some arguing the Select II stones were wasted on even A2, because the less aggressive Sigma Power line cut A2 just fine and wore slower.

Me? I've mostly settled on easier to sharpen steels (Ashley Iles, with some similar O-1 and some PM-V11) and this is just clear memories of experiments others have reported. YMMV!

[Andrew Pitonyak]

Shapton clearly states that they do not have "super steel", which I assume means really hard.

I did all shapton, but have not heard back. It surprised me that given how long these have been available, that people have not had experience with them here.

[Warren Mickley]

Shapton HR "High Resistance" are designed for stainless steels like PMv11 and semi stainless steels like A1 and D1. Because these steels are abrasion resistant,
the stones are particularly harsh and aggressive. The downside is that they leave a surface that is hardly polished.

High carbon steels do not need the harsh aggressiveness of the Shapton HR because they are less abrasion resistant. They do better with a stone that polishes more and will take advantage of their fine grain structure. If you want a fine edge, you want a steel without all the chrome that goes into stainless. My guess is that the Shapton HC are considerably less harsh.

[Andrew Pitonyak]

Shapton HR "High Resistance" are designed for stainless steels like PMv11 and semi stainless steels like A1 and D1. Because these steels are abrasion resistant,
the stones are particularly harsh and aggressive. The downside is that they leave a surface that is hardly polished.

High carbon steels do not need the harsh aggressiveness of the Shapton HR because they are less abrasion resistant. They do better with a stone that polishes more and will take advantage of their fine grain structure. If you want a fine edge, you want a steel without all the chrome that goes into stainless. My guess is that the Shapton HC are considerably less harsh.

That sounds like a very good way to put it. I will use to sharpen:



PM-V11 things (better with HR)
Lie Nielsen plane blades, but I do not think that it was billed as anything fancy, and they are at least 10+ years old.
Old chisels. I have no idea what steel these are, what did the older (50+ years) stanley chisels use.
Old plane blades
Kitchen knives (better with HR)
pocket knives, almost ALL of them are stainless (better with HR)


So, unless some of my older chisels, plane blades, my few knives that are old enough that they are not stainless (kitchen and pocket knife) would be better with HC, I am probably better off with HR.

While thinking about blades that have different hardness, this is on Shapton's FAQ page:


Question: I want to try using "KUROMAKU Purple" (30,000) , but the 'Precautions' state it should be used after "KUROMAKU Melon" (8,000)－ would it be OK to use it for sharpening after "KUROMAKU Yellow" (12,000) instead, as this is finer?

Answer: That would be fine with high hardness steel, but for blades made from softer materials, please do use "KUROMAKU Melon" (8,000). This is due to the stones' physical characteristics.

I absolutely did NOT expect to this answer. For a "less-hard" steel, they want you to go directly from 8K to 30K. Then again, this advise may only be applicable to the 30K stone since they also have this:

Question: When I am using the ultra-fine "Purple" (30,000) stone I get the feeling that it isn't actually doing any sharpening.
Answer: When you are using the "Purple" (30,000) stone to finish hone an edge and it feels like it isn't really removing any steel or sharpening as other stones do, this is usually because one is working on too wide a surface. The stone is designed to be used on just the last millimeter of the edge, and if used properly will leave the blade sharper than it has ever been before.

How big is a micro-bevel?

The only thing I had considered prior to the last week was things such as this:



Some abrasives are harder than others (aluminum oxide, carbide, diamond, etc) so you need something harder for really hard steel.
Abrasives affect the edge differently, which is usually only discussed in the context of a diamond may leave a "jagged" edge.

[David Bassett]

... While thinking about blades that have different hardness, ....

I suspect you aren't distinguishing the general "hardness", e.g. HRc 62 (or whatever), or the iron/blade with much harder carbide particles in the high alloy steels which help it hold* an edge and make it harder to sharpen. Lots of threads discuss which abrasives cut which carbides present in which steel. Plain steels, carbon & iron, can be heat treated and tempered to remain very hard, e.g. Japanese blades in White #1 at HRc 65+, and still be relatively easy to sharpen.

(* Warren may drop back in to point out it is an inferior edge that is lasting longer. Depending on what you're doing this may or may not be important. E.g. carbide router bits seem an advantage in MDF, but much less so for delicate hand carvings.)

[Warren Mickley]

I suspect you aren't distinguishing the general "hardness", e.g. HRc 62 (or whatever), or the iron/blade with much harder carbide particles in the high alloy steels which help it hold* an edge and make it harder to sharpen. Lots of threads discuss which abrasives cut which carbides present in which steel. Plain steels, carbon & iron, can be heat treated and tempered to remain very hard, e.g. Japanese blades in White #1 at HRc 65+, and still be relatively easy to sharpen.

(* Warren may drop back in to point out it is an inferior edge that is lasting longer. Depending on what you're doing this may or may not be important. E.g. carbide router bits seem an advantage in MDF, but much less so for delicate hand carvings.)

Yes, I was thinking same thing, David. Andrew seems to confuse hardness with abrasion resistance, which makes analysis confusing. High carbon steels can be harder or softer depending on how they are tempered. I suspect that people with high carbon steels were not getting the highly refined edges with Shaptons that they got with other types of stones and Shapton was trying to solve the problem.

[Tony Zaffuto]

Some very excellent points being made, that are well known, but outside woodworking! For example, in my industry (powder metallurgy), D2 is a tool steel that has a primary use for dies and a lesser extent, pins. It is not typically used for cored punches and when it is, it is typically subjected to a double draw, which would lead one to wonder why the toolmaker just didn't use a more suitable material in the first place. A2 or S7 would be a suitable use for punches.

In woodworking, I'm wondering why A2 was introduced for plane blades and chisels in the first place (always seem to have extra mumbo jumbo applied, such as cryo treatment). I also wonder why, when a vendor introduces a product, why they also don't give sharpening suggestions, tailored to the process used to make their products.

I also am of the opinion, that Lee Valley did a superb job with the development of their PMV-11 material and view it as a step forward with edge tool steels, while I also feel that A2 was a step backward. Lee Valley developed a material specifically tailored to the job. I am not sure who introduced A2, but it almost seems a tool steel specs were read and the material introduced, without full understanding if it was appropriate to the job being asked of it, in the specific shape of the tool in which it was used.

[ken hatch]

Some very excellent points being made, that are well known, but outside woodworking! For example, in my industry (powder metallurgy), D2 is a tool steel that has a primary use for dies and a lesser extent, pins. It is not typically used for cored punches and when it is, it is typically subjected to a double draw, which would lead one to wonder why the toolmaker just didn't use a more suitable material in the first place. A2 or S7 would be a suitable use for punches.

In woodworking, I'm wondering why A2 was introduced for plane blades and chisels in the first place (always seem to have extra mumbo jumbo applied, such as cryo treatment). I also wonder why, when a vendor introduces a product, why they also don't give sharpening suggestions, tailored to the process used to make their products.

I also am of the opinion, that Lee Valley did a superb job with the development of their PMV-11 material and view it as a step forward with edge tool steels, while I also feel that A2 was a step backward. Lee Valley developed a material specifically tailored to the job. I am not sure who introduced A2, but it almost seems a tool steel specs were read and the material introduced, without full understanding if it was appropriate to the job being asked of it, in the specific shape of the tool in which it was used.

Tony,

Thank you,

ken

[Andrew Pitonyak]

Andrew seems to confuse hardness with abrasion resistance

Nailed it! Thanks for the re-enforcement.

[Andrew Pitonyak]

Plain steels, carbon & iron, can be heat treated and tempered to remain very hard, e.g. Japanese blades in White #1 at HRc 65+, and still be relatively easy to sharpen.

And those seem to be the sort of thing that the HC is looking to improve upon.

[Andrew Pitonyak]

I also just noticed this: They use different abrasive agents. GlassStone series 50603, 50703 and 50803 are recommended for sharpening composite steel blades, where steel has been forge welded with another metal.

I thought that a "composite blade" meant that the edge was a different steel than the entire blade. Strange.