ZDP-189 Opinions?

[Donut]

Good info. Thanks for the comparison to S90V, apparently Sal was talking about CATRA. :)

Looking at the elements, there is a lot of Chromium. People say that since the Chromium is used to form the carbides is why it isn't as stain resistant and rust resistant as the elements make you believe.

IMO, hijack all you want, thread is about steel with (my) preference towards ZDP.

[The Mastiff]

I recall reading about ZDP right before Spyderco brought out their first model in it. It was the most exotic steel I'd heard of until that time, and I was pretty used to tool steels. It is an amazing steel performance wise and sometimes we forget that. We now are used to the ZDP's, and S90V's and kind of take them for granted. Heck, there was a time S30V was a huge leap forward compared to the stainless steels I grew up with. Mainly 440A, and 420J, with 440C in the expensive knives I couldn't afford back then.

I find ZDP easy to sharpen and agree it's a finesse steel. I always recommend a light touch when sharpening. I use diamonds to make things easy, and stop at DMT red ( fine) where it still has a good bite.

Donut, the high chromium numbers are turned into carbides by the extremely high carbon content leaving some free chrome, but not enough to make ZDP as corrosion resistant as some other stainless steels. IMO, it's similar to ATS 34 run hard (rc61) in it's corrosion resistance. The heat treat is more designed to enhance wear resistance rather than corrosion resistance in my opinion, though I don't know Spyderco's specific formula. Those are typically not talked about by companies and are sort of a trade secret. Spyderco obviously doesn't run it as hard as they can, and I can understand why. They do a great job with it and in my opinion, every knife knut should have one if for no other reason than to try this true super steel out.

Joe

[jackknifeh]

If you don't baby the blades then the real difference is with you. If you are anal about your edge and can't handle chips you will probably be more happier with VG-10.

I've agreed with a couple of posts as I've read so far but this one sums it up the best. I'm the guy that micro chips bother. And, I do consider it anal or being too picky. I think I could handle them easier if the edge stayed sharp longer than it does. ZDP does have great edge retention but for me it doesn't outweigh other things. I had a hard time sharpening it at first. I just couldn't get it sharp when I could get any other steel I've used VERY sharp. My skill level was the problem. Now I have no problem at all. If I use a back bevel of whatever I want to increase slicing ability I still need a 36 or 40 degree edge bevel to lower the micro chipping to an acceptable lever FOR ME.

So, I won't NOT but a knife because it has ZDP but I'd rather have S30V or VG-10. It has been mentioned in this thread that today's GREAT steel is tomorror's average steel. Just like AUS-8 or 440C from what I've read and heard. The thing that solidified my feeling about ZDP-189 was cutting french fries. The potatoe was very hard on the steel and the razor edge was gone almost immediately. M4 and S30V performed MUCH better and would still slice phone book paper with ease after cutting up 3 or 4 potatoes.

These are my feelings and no more accurate as a whole than anyone's. In fact there are so many more people who have much more experience than me and love ZDP.


Jack

[chuck_roxas45]

Well, I would prefer a knife in ZDP over one in VG-10. ZDP's failure mode is chipping rather than rolling. It is what it is and you live with that. It does hold that edge for a long time. And it is lucky that we have knives like endura, delica, and stretch in ZDP. And yes, we are spoiled when it comes to steels. :D

[TBob]

ZDP-189 is my favorite knife steel at the moment. ZDP-189 holds a great cutting edge for a long time, as Cliff's graph indicated. I don't have any trouble sharpening it when needed, but frankly, for me that isn't very often. My EDC is the Stretch CF w/ZDP-189, and it's like the Energizer Bunny - it cuts and cuts and cuts...

Knowing that ZDP-189 isn't really stainless, I wash it off every time I cut food with it. I also hit it with a Silicon cloth every few weeks, like I do for CPM-M4.

I consider the entirety of a knife's design and utility before buying, so the blade steel isn't generally a make or break. Even so, I did pre-order the Manbug in ZDP-189 largely because of the steel.

[jackknifeh]

ZDP-189 is my favorite knife steel at the moment. ZDP-189 holds a great cutting edge for a long time, as Cliff's graph indicated. I don't have any trouble sharpening it when needed, but frankly, for me that isn't very often. My EDC is the Stretch CF w/ZDP-189, and it's like the Energizer Bunny - it cuts and cuts and cuts...

Knowing that ZDP-189 isn't really stainless, I wash it off every time I cut food with it. I also hit it with a Silicon cloth every few weeks, like I do for CPM-M4.

I consider the entirety of a knife's design and utility before buying, so the blade steel isn't generally a make or break. Even so, I did pre-order the Manbug in ZDP-189 largely because of the steel.

If I can ask, where did you pre-order the ZDP Manbug?

Jack

[FLYcrash]

I agree with the statement that ZDP is something like S90V. (I have an S90V Mule and gave my dad a ZDP Stretch a few years back). Both hold an edge insanely long and stand up very well to abrasive media like cardboard. Their wear resistance make both hard to sharpen, nothing like VG-10 for example. Use diamond! Also, neither is all that stainless. I was sad to see a bit of rust show up on my Mule. The challenge is that the really great edge holding encourages you to be neglectful, while the lack of stainlessness punishes you for this! Good luck!

[Blerv]

It's pretty darn stainless compared to some things. I recall D2 being referred to as a "semi stainless" years ago and now certain YouTube folks say that about 8Cr13Mov. :confused: It's like H1 compared to old carbon steel from day of yore.

It may be chippy if pushed but I haven't seen it as a sissy knife owner :D . I don't know what's expected from a stainless in that 64-66 RC range. Furthermore most it's applications have THIN edges. The Stretch is probably the thickest behind the edge and that says a ton.

Another great reason the Mule project is around. It cuts half the variables out of the picture.

[Donut]

It would be interesting to see a thicker blade with ZDP. I know ZT made one or two, but how about something like the Japan made Chinook or (I know I'll be calling JD Spydo's name on this one) a Superhawk with G-10.

A dream to me would be a Captain sprint in ZDP, even though it isn't a very thick blade.

[FLYcrash]

It's pretty darn stainless compared to some things. I recall D2 being referred to as a "semi stainless" years ago and now certain YouTube folks say that about 8Cr13Mov. :confused: It's like H1 compared to old carbon steel from day of yore.

Haha, agreed. We get spoiled with all of these fantastic steels. But still, it is worth remembering that ZDP and S90V are much less corrosion resistant than VG-10, say.

[Evil D]

A dream to me would be a Captain sprint in ZDP, even though it isn't a very thick blade.

That would make for a nasty blade, but i bet that recurve section would be a PITA to sharpen.

[Blerv]

That would make for a nasty blade, but i bet that recurve section would be a PITA to sharpen.

I still keep nagging for a ZDP-189 FFG PE Harpy but nobody pays attention. :p

[Clip]

I still keep nagging for a ZDP-189 FFG PE Harpy but nobody pays attention. :p

Probably because most on here have developed an immunity to nagging. Try pestering!

[Cliff Stamp]

Not to thread-jack but have you dabbled with Super Blue?

Super Blue is essentially and F series steel which were designed to hold a sharp edge, i.e., they have high hardness, high wear resistance, fine aus-grain and very small carbides. The F series steels were phased out when the HSS started to be developed as the HSS have the same characteristics and are actually easier to HT providing you can handle the high aus-temps - and on top of that they put up with a lot more abuse in manufacturing as they are HS steels after all so you can't burn them in grinding (without difficulty).

Super Blue should thus act like a HSS as a knife with the exception that without the alloying elements that make it HS so it will tarnish easier. The other way to look at Super Blue is take something like 52100 and remove the requirement for toughness / large blades and you would end up wanting Super Blue, a bit harder, a bit more wear resistant but the same easy to sharpen to a very high finish.


All of that being said, I have used HSS, the white series Japanese steels (which are just high cementite / very pure 1095), but not the Super Blue.

[kbuzbee]

Super Blue is essentially and F series steel which were designed to hold a sharp edge, i.e., they have high hardness, high wear resistance, fine aus-grain and very small carbides.

I'll second what Cliff said. It takes a screaming edge and from the feel of it I'd think the carbides are very small. Easily my second favorite steel.

Ken

[Donut]

I still keep nagging for a *ignored* but nobody pays attention. :p

Yeah, I think you're right. :D

[Ankerson]

ZDP-189 is an excellent steel, it does hold an edge for a long time, somewhat better than S30V due to the high hardness (65 HRC), high percentage of Carbon and Chromium.

A few things though, with the high hardness range and a lot of the Chromium tied up in Carbides it's not as stainless as S30V, that's a trade off of both the high hardness and edge retention.

It's also very fine grained, will take a very refined edge, although a coarser edge will generally cut better in slicing and edge retention will be also be better.

I would like to note a few things I have noticed in this thread.

CPM S90V (CPM 420V) was out awhile before S30V was introduced along with CPM S60V (CPM 440V) and CPM 10V (Crucibles 1st PM Steel) so these steels have been around for a very long time now, S30V is the new kid on the block compared to them.

S30V was introduced to the knife world because it was easier to work with and finish than S90V was and no Chris Reeve didn't invent S30V or have anything to do with the development of it as Crucible already had the steel before Chris Reeve knew about it. Some others were working with S30V before Chris Reeve so he was just one of that very small group, although he was the 1st to put it in a production knife. Also the 1st run of S30V is different that what we have today and would take a higher hardness of around 62 HRC.

[Donut]

Jim, thanks for posting. Better than S30V is very good performance, IMO.

Yeah, I have read that S30V was the first steel made specifically to be used in knives. It is a super steel in that it was made specifically for "us".

Blerv, thanks for contributing, you've mentioned some VERY useful information, the Phil Wilson summary is great.

[Ankerson]

Jim, thanks for posting. Better than S30V is very good performance, IMO.

Yeah, I have read that S30V was the first steel made specifically to be used in knives. It is a super steel in that it was made specifically for "us".

Blerv, thanks for contributing, you've mentioned some VERY useful information, the Phil Wilson summary is great.

It was adopted due to the lower vanadium content and it was easier to work with and HT than S90V so it was perfect for the production companies at that time.

It wasn't made for us as Crucible already had been making the steel but it was in use in other areas, what the makers wanted or needed was a steel that was easier to make knife blades out of than S90V so the 4% Vanadium down from 9% in S90V provided them with that answer. So what happened was a small group of people (Custom Makers) got samples to work with and figure out the best way to adapt it to use in knife blades. Once that was figured out Chris Reeve put it in his knives replacing BG-42. There is a lot of History in S30V and I won't name names and I do know who they are, those who were directly involved because I don't want to throw them under the bus.

Chris Reeve does get the credit for being the 1st to market it in use in his knives and making it popular.

It is one of the best user steels that is available for those who work with their knives.

CPM 154 was Crucibles 1st steel that was specifically made for the knife makers as the Custom guys wanted something that was easier to deal with then S30V and CPM 154 is still very popular to this day with the the Custom makers.

[The Mastiff]

To fill out some of what Cliff is saying here is the info on F2 steel. Notice that like Super blue it's a clean, high carbon steel containing Tungsten. http://www.steelss.com/Tool-steel/astm-f2.html

It should make decent knives but I've never seen any in the world of cutlery. Others have, an example of whicfh is this sort of famous early test of rope slicing of a sort.

Twelve years ago I started using a standard test to test the cutting abilities of different knife steels. All the blades I prepare for this test are the same size, shape and thickness, being .125 in. thick and flat ground. The included angle is 12 degrees to 15 degrees, with a primary sharpening angle of 15 degrees per side; final sharpening is on a Norton Fine India stone. Cuts are made on the single strands out of a 1 1/4 in. hemp rope. The single strands are easier to handle.

Three tests were conducted on each blade and the results averaged. Using a slicing cut, the strand is parted and cutting continues until the cutting edge loses its bite into the rope. This is about the same point that the edge loses its ability to shave hair.


Steel Type Rockwell "C" Hardness Number of Cuts
154 CM Freeze treated 61 44
154 CM Not freeze treated 60 38*
ATS 34 Freeze treated 60 38
440-C Freeze treated 58 33
440-C Not freeze treated ? 25*
CPM T440-V ? 58
VASCOWEAR 61 56
D-2 60 47
D-5 61 52
D-5 59 40*
Stellite 6-K 44 58
F-8 ? 45
M-2 64 44
52100 Handforged 60 43
5160 Handforged 60 43
O-7 Handforged 61 44
*Note the difference that two points of Rockwell hardness makes, also the loss of edge holding when freeze treating is not used.

There is a lot of difference in rope; some is more abrasive than others. I keep a standard knife on hand to compare all others to; this will tell you also when your rope changes.
W. L. Goddard

Take note of how well Vascowear/Cruwear/mastiffwear performs compared to other notable and high performing steels........... :)

URL for above: http://sharpeningmadeeasy.com/edge.htm



Joe