What are the advantages and disadvantages of ZDP-189?

Josh K said:
Does not shave hairs is not dull, and twenty minutes of whittling (depending on your initial edge) will dull it a bit.

Have you sharpened it at all?
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No I haven't sharpened it yet. It shaved hairs straight from Spyderco.
The Pivot play is minor and on second thought I shouldn't have mentioned it since this thread is about ZDP-189.

Have you had edge chiping?
I cut a plastic clam shell and that put another chip (small) in the edge.
Isn't ZDP-189 supposed to be tougher after you get through the top "layer"?

I'm guessing I will need the diamond sharpmaker to clean up the edge and get the top layer off.

These are small chips, but I'm surpised to have them at all because I remember reading about people using ZDP-189 to cut dry wall and carpet! That has to be harsh.

-James
 
James007 said:
No I haven't sharpened it yet. It shaved hairs straight from Spyderco.
The Pivot play is minor and on second thought I shouldn't have mentioned it since this thread is about ZDP-189.

Have you had edge chiping?
I cut a plastic clam shell and that put another chip (small) in the edge.
Isn't ZDP-189 supposed to be tougher after you get through the top "layer"?

I'm guessing I will need the diamond sharpmaker to clean up the edge and get the top layer off.

These are small chips, but I'm surpised to have them at all because I remember reading about people using ZDP-189 to cut dry wall and carpet! That has to be harsh.

-James
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What steel was able to shave hair after 20 minutes of whittling pine? I like to try this myself.

Thanks, Vassili.

As I sad I use any chance to try my Yuna Hard II and last Saturday I fix some sprinkles and use it to cut roots and dig around sprinkle carefully to not to damage inner tube.

Yuna-Hard-II-032.jpg


No chips - nothing. I had to resharpen it of course after this use, but damage I think was way less then other steel will have in same situations.
 
Josh K said:
M4 is amazing, and S90V holds an incredible edge, but ZDP will take a finer edge then either of them. For finess ZDP wins out, for shear toughness and edge holding go with S90V.
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I'm pretty sure that the CPM-M4 is much tougher than both ZDP-189 and S90V. It can hold an a really acute edge w/o chipping.

Also, how do you tell if a knife has a fine edge? Even the steels with large carbide structures like 440C and ATS34, I can get sharp enough to pop hairs (as in shave my arm hair right in the middle of the hair by simply gliding through).

Someone used an electron microscope and all the tested steels had an edge thickness of 0.4 to 0.5 microns when sharpened to the max. Some steels are easier to get that sharp edge though, because they don't burr. But I think the maximum sharpness between all the steels are pretty close.
 
cotdt said:
I'm pretty sure that the CPM-M4 is much tougher than both ZDP-189 and S90V. It can hold an a really acute edge w/o chipping.

Also, how do you tell if a knife has a fine edge? Even the steels with large carbide structures like 440C and ATS34, I can get sharp enough to pop hairs (as in shave my arm hair right in the middle of the hair by simply gliding through).

Someone used an electron microscope and all the tested steels had an edge thickness of 0.4 to 0.5 microns when sharpened to the max. Some steels are easier to get that sharp edge though, because they don't burr. But I think the maximum sharpness between all the steels are pretty close.
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Knife has fine edge if it whittle hair:

http://www.youtube.com/watch?v=f7_WmzNjmos

Which is equa to 10-20 on thread cutting test.

ZDP189 holds this edge clearly better then CPM M4. See test results here:

http://playground.sun.com/~vasya/Manila-Rope-Results.html

Thanks, Vassili.

P.S. Popped hairs indicated coarse edge when they stuck between teeth and then ripped out under tension which give them momentum to pop up.
 
gajinoz said:
As long as you use the thing reasonably sensibly, (not as a prybar, screwdriver, digging your way out of a battle tank, etc), I think you will be impressed with it.
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And why shouldn't you be able to use it as a prybar? My A2 knife could be used as a prybar. I could bend the entire blade 90° degrees, it would simply snap back perfectly. No broken tips ever. The tip would never chip, just flex and flex back 100%, all that despite being harder than most of the stainless steels that do tend to edge chip.

My point is, since ZDP-189 is not that stain resistant anyway, why not get CPM-M4 instead?

nozh2002 said:
Knife has fine edge if it whittle hair:

http://www.youtube.com/watch?v=f7_WmzNjmos

Which is equa to 10-20 on thread cutting test.

ZDP189 holds this edge clearly better then CPM M4. See test results here:

http://playground.sun.com/~vasya/Manila-Rope-Results.html

Thanks, Vassili.

P.S. Popped hairs indicated coarse edge when they stuck between teeth and then ripped out under tension which give them momentum to pop up.
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Yeah but my point is that M4 is tougher. Edge retention when only cutting soft objects is not a big deal to most people.
 
I'm puzzled. My experience is very different. I whittled a pine 2X4 for twenty minutes with my new Stretch II ZDP-189 and it is already dull (does not shave hairs) and the edge has 4 (small) chips.

The Stretch II does whittle slightly better than my $2 kitchen knife, but the $2 kitchen knife hurts my hand a lot less. I'm also suprised that after ony twenty minutes the Strech's pivot has vertical and horizontal play.

Obviously I'm not a knife nut, my only other Spyderco is a Ladybug H1 for light use.

Is whittleing pine 2X4's asking too much for ZDP-189?
Did I get a ZDP-189 with bad heat treatment and a weak pivot
Should a stretch II be saved for easier stuff like vegetables, rope, and cardbord.

Did I buy the wrong knife, would a Manix 2 be more better for general use?

Does anybody else use the Stretch II for more than a few minutes and notice the steel liners have sharp edges and really dig into your palm and pinky?
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James007, you shouldn't be puzzled. If you were pressing, and torquing so hard that you destroyed your knife, and hurt your hand your knife isn't at fault. Your technique is the problem. You just needlessly destroyed a near $200 knife.Without doubt one of the best Spyderco has ever made.

I'm not even sure if recommending a fixed blade knife is the answer to your troubles. A stout, well built fixed blade with a comfortable handle would suit you more I'd guess. Also, slowing down, not cutting as deeply, and twisting the blade should help. If you are forcing it so hard that you hurt your hand you should back off a bit, take shallower cuts and use the knife to cut, not force it in and try to pry the wood off.
 
And why shouldn't you be able to use it as a prybar? My A2 knife could be used as a prybar. I could bend the entire blade 90° degrees, it would simply snap back perfectly. No broken tips ever. The tip would never chip, just flex and flex back 100%, all that despite being harder than most of the stainless steels that do tend to edge chip.
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Pictures or it didn't happen. :)
 
cotdt said:
And why shouldn't you be able to use it as a prybar? My A2 knife could be used as a prybar. I could bend the entire blade 90° degrees, it would simply snap back perfectly. No broken tips ever. The tip would never chip, just flex and flex back 100%, all that despite being harder than most of the stainless steels that do tend to edge chip.

My point is, since ZDP-189 is not that stain resistant anyway, why not get CPM-M4 instead?



Yeah but my point is that M4 is tougher. Edge retention when only cutting soft objects is not a big deal to most people.
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ZDP-189 is far more stain resistant then M4. If your point is "it will stain anyways" that's pretty much mute. Everything will stain, even titanium and H1 when exposed properly.

ZDP-189 takes a much finer edge then M4, on top of being stainless.
 
have actually found M4 to get a bit sharper than ZDP-189, but not too much sharper. They are the 2 steels I own that get the sharpest. My M4 is on a Krein custom and a Spyderco Mule, and I use Shapton Glasstones and 3M lapping film to put the edge on each. ZDP is definately more stain resistant, but M4 is tougher ans for me gets sharper. The sharpness is relative though, as most people handling each knife would be scared of the edges, but in whittling hair and other sharpness tests the M4 just gets a bit sharper for me.

Mike
 
cotdt said:
Yeah but my point is that M4 is tougher. Edge retention when only cutting soft objects is not a big deal to most people.
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Manila rope is not soft object. You make it sound like I am talking about bread or something. ZDP189 is superior to CPM M4 in edge holding. CPM M4 is very good steel, better then many, but behind ZDP189.

Manila rope is harder them what most people cutting. This is why manyla rope is media for many knife tests, including ABS competitions.

It is shame that American metallurgist can not offer anything like ZDP for production knives and only Dozier with his magic HT keep first place.

Thanks, Vassili.
 
I am wondering about number of posts you guys have - 5 and 3 - what is this. One time accounts just for this thread?

A2 and CPM M4 are good steels, but not as good as ZDP189. ZDP189 is not available for most knife manufacturers here for some reason, but it does not make it's edge holding any less. This is best steel on the market now and no one can do 67HRC or even 65HRC when it is especially tough, so this is unfortunate that it can be only imported from Japan for so many years, but it does not make it worse in terms of performance.

Thanks, Vassili.
 
gunmike1 said:
have actually found M4 to get a bit sharper than ZDP-189, but not too much sharper. They are the 2 steels I own that get the sharpest. My M4 is on a Krein custom and a Spyderco Mule, and I use Shapton Glasstones and 3M lapping film to put the edge on each. ZDP is definately more stain resistant, but M4 is tougher ans for me gets sharper. The sharpness is relative though, as most people handling each knife would be scared of the edges, but in whittling hair and other sharpness tests the M4 just gets a bit sharper for me.

Mike
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I do not see any difference in CPM M4, CPM S90 and ZDP189 I have on Mule 2, 3 and 4. I just recently resharpen all of them and all of them whittle hair just fine.

Thanks, Vassili.
 
Good grief, said I would never do it...but I must now use ignore feature, and I'm serious this time:p


edit-ahh, much better.
 
nozh2002 said:
Manila rope is not soft object. You make it sound like I am talking about bread or something. ZDP189 is superior to CPM M4 in edge holding. CPM M4 is very good steel, better then many, but behind ZDP189.

Manila rope is harder them what most people cutting. This is why manyla rope is media for many knife tests, including ABS competitions.

It is shame that American metallurgist can not offer anything like ZDP for production knives and only Dozier with his magic HT keep first place.

Thanks, Vassili.
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Or his magic edge geometry, or the width of the blade, or how much it's sharpened, or the hardness of the steel, or how far you bite into that wood base you built when chopping your rope.

A lot more goes into testing edge retention then cutting string and rope.
 
Josh K said:
Or his magic edge geometry, or the width of the blade, or how much it's sharpened, or the hardness of the steel, or how far you bite into that wood base you built when chopping your rope.

A lot more goes into testing edge retention then cutting string and rope.
Click to expand...

Once again - you need to learn what are you talking about. Just read my testing page, testing thread - all explanations are there if you will to read.

Influence of edge geometry, blade width, initial sharpness level and wooden base as well as many other influences were eliminated. So test show only steel ability (with given HT of course, so different manufacturers had different results in this test).

Thanks, Vassili.

P.S. I do not want to go over again with you just because you are new to the forum - find that thread and read it and if you have question - post them on that thread.
 
nozh2002 said:
Once again - you need to learn what are you talking about. Just read my testing page, testing thread - all explanations are there if you will to read.

Influence of edge geometry, blade width, initial sharpness level and wooden base as well as many other influences were eliminated. So test show only steel ability (with given HT of course, so different manufacturers had different results in this test).

Thanks, Vassili.

P.S. I do not want to go over again with you just because you are new to the forum - find that thread and read it and if you have question - post them on that thread.
Click to expand...

Do you have a link to that thread handy? I have read it, just not recently. I'm curious to know how you eliminated the base as a factor, as well as initial sharpness level, blade thickness, and all the other factors I mentioned.
 
Interesting, exactly what prevents edge geometry, hitting the wooden base plate (it sounds like you are in both those videos), initial sharpness (whittling hair isn't a defined level), thickness of the blade (thicker blade, more resistance to cutting, thicker edge = harder to cut).
 
Josh K said:
Interesting, exactly what prevents edge geometry, hitting the wooden base plate (it sounds like you are in both those videos), initial sharpness (whittling hair isn't a defined level), thickness of the blade (thicker blade, more resistance to cutting, thicker edge = harder to cut).
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I do not want to take over this thread.
I do not want to go over this again.
Can someone who able to do search point Josh K to right thread?

Thanks, Vassili.

P.S. I found it http://www.bladeforums.com/forums/showthread.php?t=589139
 
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nozh2002 said:
I do not want to take over this thread.
I do not want to go over this again.
Can someone who able to do search point Josh K to right thread?

Thanks, Vassili.
Click to expand...

Sent you an email, I don't want to hijack. :)
 
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