ZDP-189 vs. CPM S90V

[shangchi108]

I have several Spyderco knives with blades made of ZDP-189, and they are excellent performers. I've gone to the trouble of reprofiling two of them and they weren't that hard to do, and now have scary aggressive cutting edges.

I once owned a knife made from S60V (CPM 440V) and it was a bitch to sharpen. ZDP is definitely superior in that regard.

What I want to ask is this: Is S90V the closest American competitor that ZDP-189 has? It seems that everyone who has both steels seems to prefer S90V, though everyone mentions how difficult it is to sharpen. Is it possible that S90V is the next ultimate exotic steel that will replace ZDP-189 in Spyderco's lineup?

In comparison, and for the purpose of discussion, I'm entirely happy with the performance of VG-10. S30V is supposedly better, but it can't be by much, since in my informal tests, they seem to have equal durability in edge holding, doing roughly the same work, and I'm entirely happy with either steel, though VG-10 seems to be cheaper. My ZDP knives out cut VG-10 roughly 4 to 1, in terms of edge holding, and aren't that much harder to sharpen, so I'm very happy and impressed with the performance of ZDP. I haven't noticed any of the rust problems that others have reported.

Since S90V is a domestic steel, is it more economical to use than ZDP? Do you all think that S90V offers enough of an advantage over ZDP-189 to be the preferred steel?

 

[THG]

Ask Yablanowitz. He says S90V has ~25% better edge retention than ZDP-189.

 

[Joshua J.]

As far as Spyderco is concerned it more comes down to where the knife is made than which one is superior. Seki models get ZDP-189, and USA models get S90V. I'm sure both steel types will be in use for a very long time.
Though, S90V may get replaced by the upcoming S110V.
CPM S110V is more of an enhanced version of CPM S90V than it is a whole new steel type (think of it as S90V+). It should perform a little better in most areas, but it's still not the kind of steel we were looking for in CPM S125V, which is so hard and wear resistant no-one can efficiently manufacture knives out of it, and only the bravest custom makers use it.

 

[THG]

The only Spyderco that uses S90V is the Military (sprint run). Other than that, the USA models generally use S30V.

 

[gine]

Ask Yablanowitz. He says S90V has ~25% better edge retention than ZDP-189.

Yes he did say that, But he cuts abrasive materials like carpet and drywall.

cpm s90v has a higher wear resistance and a rc at about 59.Zdp-189 on the

other hand has better edge stability and takes a keaner edge,with a

rc at 66.I all depends what materal you are cutting, but all in all they are

great steels to play with.

thx gine.

 

[yablanowitz]

Yup. For me, doing the work I do with a knife, S90V is a noticeable improvement over ZDP-189. I cannot stress enough, my use is not typical.

I use my knives hard enough to tell the difference between premium steels, and abrasion resistence is a major consideration for me because of all the abrasive stuff I deal with. High abrasion resistence means sharpening takes longer, but the edge lasts longer. I can handle that. Diamonds don't care how hard that steel thinks it is. I never noticed S60V/440V being difficult to sharpen...on diamond hones. S90V isn't difficult either. It just takes longer. It took a couple of hours of relaxed work to put a hair-popping edge back on my S90V Military last night...after two days of drywall work that would have trashed a couple of ZDP edges (voice of experience).

My understanding is that CATRA testing showed S90V and ZDP-189 to be equals. Both are great steels, and hold an edge for a very long time in what I call light use (and most people call normal use). I'd like to see more S90V used, but I'm not sure how much of a demand there would be. I wouldn't call it a mainstream steel any more than ZDP. Both are more for the afi market.

 

[shangchi108]

I use my knives hard enough to tell the difference between premium steels, and abrasion resistence is a major consideration for me because of all the abrasive stuff I deal with. High abrasion resistence means sharpening takes longer, but the edge lasts longer. I can handle that. Diamonds don't care how hard that steel thinks it is. I never noticed S60V/440V being difficult to sharpen...on diamond hones. S90V isn't difficult either. It just takes longer.

I use diamond hones to reprofile my blades. I use a Spyderco Sharpmaker to touch up my knives. When I said it was more difficult to sharpen 440V, I didn't mean it required more effort on my part per stroke, but that it took more time. Ten minutes to sharpen VG-10 vs. 45 minutes to do the same work on 440V translates to a harder blade to sharpen (and by that I mean reprofiling).

It's a moot point, since I believe Crucible doesn't manufacture S60V anymore.

Have you tried using serrated blades to do the work you do? Serrated edge configurations tend to maintain their cutting ability long after plain edges go dull.

 

[yablanowitz]

Yes, I have tried serrations. They turn into PE pretty quick.

Just kidding. I find serrations a royal pain in the butt for most of what I do. They are OK for demolition work I guess, but the chisel grind trying to cut in a circle is tiresome and annoying. That and the teeth always dig in just when I don't want them to (assuming I haven't hit anything hard enough to tear them off). Aside from tree and shrub pruning, they aren't worth the aggravation to me.

 

[Vivi]

How dull do you let your knives get that it takes 10 minutes to resharpen a VG10 knife? I generally use 4-6 passes per side on a DMT fine stone to restore a dulled VG10 knife of my own, the whole process takes about a minute unless I strop afterwards, which adds another ~20 seconds.

 

[shangchi108]

How dull do you let your knives get that it takes 10 minutes to resharpen a VG10 knife? I generally use 4-6 passes per side on a DMT fine stone to restore a dulled VG10 knife of my own, the whole process takes about a minute unless I strop afterwards, which adds another ~20 seconds.

If you read very, very carefully, you will see that I was referring to "reprofiling", and not just touching up the blade.