ZDP-189 and Cowry-X: Overrated or Super Steel?

Only ZDP 189 I have is the Spyderco Endura
The edge holds up nicely
Diamond stones and ceramics seem to be the only thing that sharpens it in a reasonable amount of time
Pocket sweat definitely causes corrosion but I've only ever had light surface rust from pocket sweat and saltwater fishing.
By this I mean it gets light surface rust very easily but it doesn't pit down into the steel like 1095 carbon

The edge can be a bit chippy, but I haven't had any damage that couldn't be repaired with a coarse diamond stone.
The worst chip I've had is about a third of the secondary bevel and the micro bevel always chips, but the steel seems to maintain a working edge
However, the Endura is a thin example of ZDP and thin Spydercos tend to keep a working edge from thin stock and FFG as much as the blade steel used.

It doesn't corrode like a more traditional carbon steel like 52100 but it definitely isn't stainless like s30v or 110v etc.
 
I haven't read the doom and gloom yet; I just started on the thread.
Only a few posts in I have to say : Keep this up and we will all be telling the knife makers all we are capable of using is 1085 or what ever the heck.
NO THANK YOU.
I've had zero "rusting" issues with ZDP-189 in fact once I read years ago that it isn't a stainless because the chromium is used up in carbides I kept waiting to see at least some tarnish. As best as I can make out it is ever so slightly brownish over all. I mean I can't really see much at all and may just be making it up.
So much for "rusting" I mean I usually try to tarnish my tool steel because I like it that way and nothing.
IMG_4104.jpg

As far as chipping I chipped the little Dragon the tiniest, tiniest little bit while cutting wire ties. Since I don't like cutting wire ties as a rule with a knife I just use the nippers shown on a day to day basis at work and I cut a lot of wire ties. Safer for the products I am working on anyway and safer for me.

Since I stopped doing dumb things with the ZDP and just use them like knives.
Nothing but smiles here. Give me all the carbon you gots . . .
I'll trade you carbon for these and you can go to town.
IMG_3584.jpg
 
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Traded the my Manix S110V for the Endura ZDP-189 and would do it again before you could say "working edge".
 
I haven't read the doom and gloom yet; I just started on the thread.
Only a few posts in I have to say : Keep this up and we will all be telling the knife makers all we are capable of using is 1085 or what ever the heck.
NOT THANK YOU.
I don’t see how anything in my article or this thread points to that at all. But at least you admitted to not reading anything before offering your opinion.
 
I don’t see how anything in my article or this thread points to that at all. But at least you admitted to not reading anything before offering your opinion.

Welcome to the club... :rolleyes:

On to ZDP-189: I've been championing the stuff for years now.

It's definitely not stainless. Why Hitachi ever thought it was ok or accurate to call it stainless is beyond me. It's certainly closer to stainless than something like Super Blue, but doesn't quite make it there. "Stain resistant for easy maintenance" probably would've been better.

That said, it is easy to prevent rust. Dry after washing. Rub with mineral oil if exposed to high humidity or sweat. Mine are all rust free.

As far as edge retention goes, I don't doubt the edge retention tests, but anecdotally I've had better edge retention from ZDP-189 than any other steel(including the m390 family, s90v and maxamet).

My criteria is different though. I'm not speaking about a "working edge", I'm talking about a "perfect" one. Fine enough to glide smoothly when drawn across a finger nail, but keen enough to pop hairs. I would have been annoyed with and resharpened an edge long before it reached failure in a CATRA test.

ZDP-189, likely due to the carbide differences mentioned in your article, seems to respond more readily to stropping for routine edge maintenance than some of the high performance stainless options.

I love ZDP-189. It's still the best as far as I'm concerned, at least for someone who's way too anal about the state of their edge. (Yes, I'm admittedly a ZDP fanboy.)

Thanks for the great article as usual. It's interesting to see the science behind what were just basic observations during use. I'm just a dummy who makes planes collide and cuts stuff. :D
 
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I’ve never dried or oiled my ZDP. Sharpen about every 6 mos. No chipping, no rust. I have about every kind of steel blade plus Titanium, Ceramic, Stellite stuff. Guess what rises to the top? I’m a non-anal fanboy. Friction forged D-2 and Carbidized blades don’t hold a candle.
I sometimes “steel” my edge on the sides of a ceramic blade (edge leading).
 
I don’t see how anything in my article or this thread points to that at all. But at least you admitted to not reading anything before offering your opinion.

First off having used more than one example (3 examples) for years in a work environment gives me first hand experience with the "delicate little flower" and I have found the flower to be not as delicate as some seem to be tooting about.

Here you go :
bravo for telling it like it is... I've been a critic of anything with 1.5% carbon and higher, and zdp189 having double that amounts to basically cast iron - brittle nonsense (imho)

anyone using it should expect chipping edges continually, or, if the geometry really is thick enough to help minimize chipping, you'll be so thick you'll never slice well

rust issues
Many people have confirmed corrosion in their ZDP-189 knives. Of course a couple other people have told me I’m wrong and that it’s stainless.

And in your very title :
. . . Overrated . . .?
Leading one to at least suspect there might be some hypothesis in the experiments that it could be, might be, thought of as . . .
?overrated?

Do you now :
see how anything in your article or this thread points to that at all ?
 
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least you admitted to not reading anything before offering your opinion.
Noooooooo
it is you that is not reading what I wrote which was :
I haven't read the doom and gloom yet; I just started on the thread.
Only a few posts
in I have to say

So to translate : I had read your title and a few posts into the thread.
 
My criteria is different though. I'm not speaking about a "working edge", I'm talking about a "perfect" one. Fine enough to glide smoothly when drawn across a finger nail, but keen enough to pop hairs. I would have been annoyed with and resharpened an edge long before it reached failure in a CATRA test.
Sounds like we agree on the desirability of ZDP.
Why do you blank out when people have posted :
  • basically cast iron - brittle nonsense
  • expect chipping edges continually
  • [must use thick edges so will]never slice well
  • rust issues
  • confirmed corrosion
  • Overrated
And then jump on me for reporting what is ACTUALLY HERE that I HAVE SEEN.
Quite unfair really.:thumbsdown:
 
The tests are not on knives but instead on steels. The only way to test steels is to have standardized tests. Your anecdotal experiences with knives is fine, but it doesn't compare steels exactly, as heat treat and geometry do play a huge role as you guys pointed out. So you need same geometry at the very least. You also can't trully compare sharpness without a standardized test since what is sharp is different to different people, CATRA gives you that. It is great that for you guys zdp holds an edge better than any other steel, but again you are not using same geometry. You are probably not sharpening more wear resistant steels to the same level, or your mode of blunting is not wear but something else. ZDP is clearly not as stainless as what we in general consider as stainless steels. It is relatively brittle, maybe not in your application with your geometry, but toughness is low compared to steels that are generally considered tough. Its claim to fame is that it is a stainless that can get really hard, well given that it is not stainless, then there are other non stainless steels that can get really hard. This is what was reported and explained. In no way the report makes your knives all of a sudden not work for you, they work same as they did before. No need to be offended or upset. Claiming that because it doesn't stain in your use means that it is stainless is just not very convincing same as saying that it holds an edge better than anything else. It works for you, great, without standardized, rigorous tests that is all it is.
 
I read Larrin's article before this post and my impression was nothing wrong with this steel. And my impression to this steel didn't change after I read all the posts in this thread and did some google search to read other people's review on the steel. And my impression is summarized as following:

1. Edge retention: top notch no problem.
2. Stainless: just on the edge of stainless and non-stainless. Given that there is no universally consent standard of "stainless", it can be tagged as stainless or non-stainless. Fact is that it will be less stainless than most of stainless steels and more stainless than most of the non-stainless steel. The stainless data posted by the original maker seems suspicious as it rated this steel to be at the same level of stainless of 440C.
3. Toughness: OK. Per Larrin's data, it gets similar toughness as D2, N690 but at a higher HRC. So to me, if people has no complaint on D2 and N690, nothing wrong with ZDP-189's toughness.
4. Sharpening: Positive. It has chrome carbide, so will be easier to sharpen than some other high edge retention steels.

Now, the only part that might be controversial is stainless rating. For this, I believe Larrin's rating. Theory, data and experiment all set. Anecdotal experiences reported on the Internet provide very limited value to judge stainless level. As it's easy to see a lot of people reporting their 1095 never rust even living at sea coast and it's also easy to find people complain all kinds of stainless steels rust. I am not saying I don't believe those reports, in fact I do, and my conclusion is that different type of use/environment can have very different experience on stainless rating. I believe more on standard test when rating stainless. That's why I like Larrin's articles, it provides me some third party data with explanation with some theory that works on not just one steel. It will be a pain for me if the only thing I have is marketing/maker's data plus Internet posts that reports totally differently...
 
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Noooooooo
it is you that is not reading what I wrote which was :


So to translate : I had read your title and a few posts into the thread.
The main complaint in my article was that ZDP-189 is not actually stainless, and then you said if it was up to us knifemakers would keep on using the same old simple carbon steels. You apparently assumed I concluded the steel is overrated due to poor toughness despite the summary of the article saying:
Because of the false advertising of this steel as being “stainless” I give ZDP-189 the Knife Steel Nerds “Most Overrated Steel” award.
I don’t see why that means I want knifemakers to keep using nothing but “1085.”
 
Sounds like we agree on the desirability of ZDP.
Why do you blank out when people have posted :
  • basically cast iron - brittle nonsense
  • expect chipping edges continually
  • [must use thick edges so will]never slice well
  • rust issues
  • confirmed corrosion
  • Overrated
And then jump on me for reporting what is ACTUALLY HERE that I HAVE SEEN.
Quite unfair really.:thumbsdown:
I jump on you for your continued senseless diatribes. I'd have to be able to make sense of your posts before I could disagree with them.
 
One thing I find especially nice about ZDP-189 is that it does represent a low-vanadium high-carbide steel that means that you do get a significantly wear-resistant edge using chromium carbides, and so "normal" synthetic abrasives can be used to effectively sharpen it up into the higher grit ranges if you so choose instead of having to switch to super-abrasives. That being said, most of my applications that would call for a highly wear-resistant steel benefit from toothy edges, but a high chromium carbide content does mean it'll resist wear from the natural silica found all over the heckin' place in real-world use, so that's kind of a neat niche for it to occupy that not a lot of steels do.
 
Well, I'll toss my hat into what I know is the minority, but I personally do not like the stuff.

I have a Spyderco Delica in ZDP-189, I despise sharpening it. Regardless of the medium or method, I just do not like sharpening it. I can grind it no problem, so it isn't the hardness per se, but perhaps because I'm a burr-sharpener, I just struggle to properly and consistently sharpen this steel.

S30V? Check. S35VN? Check. S90V? Check.

But ZDP-189 gives me fits. At least my example. I'm never happy with the apex and seem to either fight myself or it. I know, people rave about how easy it is to sharpen, and that's awesome for them. But it has not been my experience.

I know you took exception with the steel for corrosion resistance Larrin Larrin but for me it is the above that put this steel in the most overrated category.

I'm happy for all who love it, but I do not.
 
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The main complaint in my article was that ZDP-189 is not actually stainless, and then you said if it was up to us knifemakers would keep on using the same old simple carbon steels. You apparently assumed I concluded the steel is overrated due to poor toughness despite the summary of the article saying:

I don’t see why that means I want knifemakers to keep using nothing but “1085.”

You should make your test of corrosion at higher grit finish than 400. Otherwise your results might be comparable, but are not relevant for use as a knife blade. However if you took all steels you test to 1200 grit, you might not get much drama in some of the results.

Did you use the same heat treat as William Henry? I'd guess not, since it's probably propietary. If you used the manufacturer's method for each steel type, that'd be nice to know. Doesn't heat treat effect corrosion reasistance?
 
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You should make your test of corrosion at higher grit finish than 400. Otherwise your results might be comparable, but are not relevant for use as a knife blade. However if you took all steels you test to 1200 grit, you might not get much drama in some of the results.

Did you use the same heat treat as William Henry? I'd guess not, since it's probably propietary. If you used the manufacturer's method for each steel type, that'd be nice to know. Doesn't heat treat effect corrosion reasistance?
400 grit was used to mimic production knives (approximately). The higher the finish, the better the corrosion resistance.

The heat treatments used for every steel are always given in the article. You can compare what I chose with the manufacturer datasheet.
 
Double post.
 
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This isn't the first time I've been annoyed by all the marketing around steels, especially the so called 'super-steels' and how liberal they can be with the truth, but selling carbon steel as stainless steel really takes the cake.

I've read the article, but I can't say I understand all the nitty-gritty details. In practice, how would this compare to D2 in terms of corrosion resistance?
 
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