Which blade steel can be hardened the MOST?

ZDP-189 has hit 66-68 RC if I recall correctly.

For a dedicated cardboard cutting knife why not look at some of the ceramic offerings? Brittle and you won't be able to sharpen them but I've heard great things about the edge retention. Probably wouldn't do well with wood, but I can't say for certain.

When I had my Caly3 in ZDP/CF it was an amazing slicer. Something with a thin blade in ZDP would be my choice for something like you describe.
 
ZDP-189 has hit 66-68 RC if I recall correctly.

For a dedicated cardboard cutting knife why not look at some of the ceramic offerings? Brittle and you won't be able to sharpen them but I've heard great things about the edge retention. Probably wouldn't do well with wood, but I can't say for certain.

When I had my Caly3 in ZDP/CF it was an amazing slicer. Something with a thin blade in ZDP would be my choice for something like you describe.


Is ZDP available to custom makers?
 
Just buy one of these Rocksteads and be done with it (probably should get two in case you lose one).:D

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Which blade steel can be hardened the MOST? As in achieve the highest HRC rating, and how high is that?
Crucible CPM Rex 121 steel can be hardened to 70RC on rockwell. If I am not mistaken, AISI T15 high speed steel can also go to 68-69HRC.
In general, Tungsten/Cobalt high speed tool steels are the ones designed for highest hardness. I'm not so sure how well they will work in the knives, but surely worth a try.
 
Crucible CPM Rex 121 steel can be hardened to 70RC on rockwell. If I am not mistaken, AISI T15 high speed steel can also go to 68-69HRC.
In general, Tungsten/Cobalt high speed tool steels are the ones designed for highest hardness. I'm not so sure how well they will work in the knives, but surely worth a try.

I had some chisels years ago that were plenty hard, of course, and even dropping them on cement floors from time to time didn't seem to phase them.

Some time ago, a well-known knife maker told me, if I remember correctly, that 0-1 tool steel is a very good steel. Is that the case? How does it stack up against more modern steels?
 
Some time ago, a well-known knife maker told me, if I remember correctly, that 0-1 tool steel is a very good steel. Is that the case? How does it stack up against more modern steels?
Oil hardening tool steel, I've seen it around 62HRC, as per maker's specs, but it won't go as high as others. if you are looking for highest hadness, O1 is not a candidate.
 
It may be, you would have to ask. A. G. Russell was able to import some.

Unless I'm missing something (which is entirely possible :D), the ZDP-189 knives on the A.G. Russell site are all made by manufacturers we already know to use ZDP-189. William Henry and Spyderco are listed as well as the A.G. Russel Acies and One-Hand knives which are both made to A.G. Russell specs by Kershaw. I believe all the Spyderco knives using ZDP-189 are made in Japan. I'm pretty sure the ZDP-189 William Henry uses is made and heat treated in Japan as well.....I'm not sure where the blades are ground.
 
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Unless I'm missing something (which is entirely possible :D), the ZDP-189 knives on the A.G. Russell site are all made by manufacturers we already know to use ZDP-189. William Henry and Spyderco are listed as well as the A.G. Russel Acies and One-Hand knives which are both made to A.G. Russell specs by Kershaw.

Thank you, sir.
 
Unless I'm missing something (which is entirely possible :D), the ZDP-189 knives on the A.G. Russell site are all made by manufacturers we already know to use ZDP-189. William Henry and Spyderco are listed as well as the A.G. Russel Acies and One-Hand knives which are both made to A.G. Russell specs by Kershaw. I believe all the Spyderco knives using ZDP-189 are made in Japan. I'm pretty sure the ZDP-189 William Henry uses is made and heat treated in Japan as well.....I'm not sure where the blades are ground.

Thanks, I checked out the AGR website. Some very good knives there.

Can you tell me how critical the heat treatment on the ZDP steel is, and if the various manufacturers of knives that you mentioned do a similar treatment to the steel, or if one or other is "better" than the rest?
 
It may be, you would have to ask. A. G. Russell was able to import some.

I do not think AG actually imported the ZDP. What they did is contract with Kai/Kershaw to manufacture the Acies. AFAIK, Kai/Kershaw are the only company allowed to work ZDP outside of Japan.
 
I do not think AG actually imported the ZDP. What they did is contract with Kai/Kershaw to manufacture the Acies. AFAIK, Kai/Kershaw are the only company allowed to work ZDP outside of Japan.

What about WH?
 
According to this chart by Crucible, CPM 10v would be right up your alley. I'm not positive on how accurate this chart is.

10v has a low toughness, so don't make a chopper out of it, but for slicing it should be the best. I've heard of people using it for slicing applications and saying it holds an amazing edge. I've also heard a few bad things about some crucible steel though.

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Edit: But then again, according to this chart, 9V should be the best steel for a knife period... but you don't see anyone ever using it. So like I said earlier, not sure how accurate this is.

Cody
 
What about WH?

I'm not sure how far the process goes, but I think everything short of the final grinding is done in Japan. I'm pretty sure only Kershaw gets ZDP-189 pre-HT.
 
I'm not sure how far the process goes, but I think everything short of the final grinding is done in Japan. I'm pretty sure only Kershaw gets ZDP-189 pre-HT.

Interesting, though it makes sense from a business perspective to keep the steel there.
 
Interesting, though it makes sense from a business perspective to keep the steel there.

It certainly says they want to control how the steel leaves Japan. Makes good business sense. It also says a whole lot about the excellent reputation Kershaw has acquired. :thumbup:
 
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