So, what is ZDP189 steel's claim to fame?

ThumperACC · Mar 24, 2009

Hi,

I see Spyderco using the ZDP-189 laminated steel in some of thier high end knives. Why is this steel superlative? It seems pretty simple in composition, iron, chrome and carbon (lots of carbon, 3%).

I'd like to know more about it.

Thanks,
Mike

alexcue · Mar 24, 2009

huh, i thought the laminated ZDP was on the Caly 3? What other ones are laminated?

yablanowitz · Mar 24, 2009

ZDP-189 is a proprietary steel made by Hitachi. The carbon content is high enough that it should be cast iron instead of steel, but their process manages to keep that from happening. It is typically heat treated to a Rockwell C scale hardness of 65 to 67, which is much harder than most steels will go without becoming brittle, and higher than many will go at all. Its edge holding is excellent, testing in the same range as S90V in CATRA tests, although I find S90V stands up better to my use.

For the average user, I think ZDP-189 is overkill. Most people will never push it hard enough to see what it can really do, although they may appreciate having a knife they only have to sharpen every couple of months.

ThumperACC · Mar 24, 2009

Hi Alex,

They have a Delica, an Endura, the Bob Lum Chinese and the Stretch. Look on the spyderco site, in the catalog they have a listing by blade steel. Unfortunately, the Caly3 is not in that listing though it does have the ZDP189.

Mike

ThumperACC · Mar 24, 2009

yablanowitz said:
ZDP-189 is a proprietary steel made by Hitachi. The carbon content is high enough that it should be cast iron instead of steel, but their process manages to keep that from happening. It is typically heat treated to a Rockwell C scale hardness of 65 to 67, which is much harder than most steels will go without becoming brittle, and higher than many will go at all. Its edge holding is excellent, testing in the same range as S90V in CATRA tests, although I find S90V stands up better to my use.

For the average user, I think ZDP-189 is overkill. Most people will never push it hard enough to see what it can really do, although they may appreciate having a knife they only have to sharpen every couple of months.

Ok, cool. How about sharpening? Will my Lansky croc sticks (ceramic rods) sharpen it? Or would I need diamond hones?

Mike

Ben Dover · Mar 24, 2009

ThumperACC said:
Ok, cool. How about sharpening? Will my Lansky croc sticks (ceramic rods) sharpen it? Or would I need diamond hones?

Mike

I sharpen CPM S90V and CPM M-4 with water stones on my Edge-Pro. You should have no problems with ceramic rods.

rifon2 · Mar 24, 2009

ZDP-189 is a proprietary steel made by Hitachi. The carbon content is high enough that it should be cast iron instead of steel, but their process manages to keep that from happening. It is typically heat treated to a Rockwell C scale hardness of 65 to 67, which is much harder than most steels will go without becoming brittle, and higher than many will go at all. Its edge holding is excellent, testing in the same range as S90V in CATRA tests,

...and with all of that, it doesn't require any special care.

In fact, it's a stainless steel.

alexcue · Mar 24, 2009

ThumperACC said:
Hi Alex,

They have a Delica, an Endura, the Bob Lum Chinese and the Stretch. Look on the spyderco site, in the catalog they have a listing by blade steel. Unfortunately, the Caly3 is not in that listing though it does have the ZDP189.

Mike

Mike, my apologies I must have misread your original post. The Caly 3 CF is clad (laminated) with 420j2 around the ZDP. This was the only knife i saw with this type of combo. All the others that you listed are straight ZDP.

yablanowitz · Mar 24, 2009

The Jess Horn sprint run was laminated as well. Laminated or solid ZDP depends in large part on the equipment the specific maker has available. The maker that does the Calypso series does not have a laser cutter, and their equipment can't handle cutting the solid ZDP stock. That's why the Caly Jr. and Caly 3 were made with laminated stock. The maker(s) that produce the Endura, Delica and Stretch II have the laser cutters required to cut blade blanks from solid ZDP stock, so that's what they use.

rifon2 said:
...and with all of that, it doesn't require any special care.

In fact, it's a stainless steel.

At 20% Chromium, it ought to be even more stainless than it is.

ThumperACC said:
Ok, cool. How about sharpening? Will my Lansky croc sticks (ceramic rods) sharpen it? Or would I need diamond hones?

Mike

Sal sharpens his on the SharpMaker ceramics. I use diamond hones, but that's what I've been using for everything for the last twenty years or so.

shangchi108 · Mar 25, 2009

What's so special about ZDP-189? It's harder than ME! And I'm pretty hard.

I can still strop the edge on my forearm.