Who is using CPM D2

[Noctis3880]

Yes my little World of 1/2" Manila rope cut 200 times isolated from hitting base, measuring sharpness in a process. It may be little, but it least it is real.

You created some mythical World of chatting to each other, and more you chat - more real it appear to you. You support each other and attack anyone who sceptical about your believes. Most interesting is that "testing show" which meant to prove this mythology. With "flexible" procedure and undisclosed raw data it is perfect to "prove" what you already believed.

Fortunately there was a class in University - "Scientific methodology". One of the proves of right testing is unexpected or unknown before results which then proven by independent testing.

In case of my testing - I found poor quality of SGPS, then it was also demonstrated independently by BLUNTRUTH4U. I found average performance on CPM S30V - also later CATRA tests where published with same data.

Now I rather believe in my test results then to chorus of voices here saying that CPM D2 should not be better then CPM S90V. Why should I? Show me test results (I mean real test not test show) then I may have a look. The fact that so many people here talk about that a lot - does not impressed me at all, after being on this forum for over eight years and thousands spend on super steels with average or poor performance, I learn that I should test blade performance myself and do not trust to commonly accepted opinions.

Thanks, Vassili.

Here's the thing you're not getting. Nobody is required to eliminate all variables in their own personal use. If I find S90V to last longer than D2 in cutting corn, then that's good enough for me, because I'm cutting corn and not 1/2" rope. If other people reach the same conclusion in cutting drywall, then it's also good because they are cutting drywall and not 1/2" rope. If other people reach the same conclusion cutting cardboard, then that is also good because they are cutting cardboard and not 1/2" rope.

I'm not sure how to explain this to you, but if I find that S90V does better on cardboard, drywall, fiberglass, corn, and wood, but only does bad on 1/2" rope, whereas D2 does excellent on 1/2" rope but fails at cutting drywall, wood, corn, fiberglass, and cardboard, then I'm going to go with S90V see? These are things you need to take into consideration in real world use.

And as much as I praise S90V for being an all-rounder, I think I'm still going to stick with ZDP-189 in the kitchen. So I tell you what, if I'm ever faced with a pile of 1/2" rope that needs to be cut, I promise I'll break out my Dozier Buffalo River Hunter, just for you. Okie dokie?

As cute as your supposed scientific methodology is, it doesn't seem like the real world ever factors into your equations. I say this because you yourself admitted that in your testing methods, you would continue to make the same amount of cuts with both knives even if you have to muscle down 100lbs of force on the 200th cut when most of us would have stopped at that point and called it dull. This is the crucial difference between you and Ankerson, because he acknowledges that an edge that requires more than 20 lbs of down force in a cut would no longer hold any practical use for any of us. Because I am not going to put the corn on the floor and step on the spine of the blade to force that cut see?

 

[Buffalohump]

Boy we havent had one of these for a while..... :yawn:

My two cents: I had a Para-Millie in CPM-D2 for a while and used it for the usual things. It did just fine.... I would definitely say, based on my personal experience, that it took and held an edge better than regular D2. However, I would qualify that statement by saying that the D2 knife I had was a Benchmade, and in my experience Spyderco always puts a better edge on their knives than Benchmade, out of the box.

To answer the OP's question: CPM-D2 isnt used nearly enough! Only Kershaw and Spyderco have used it, and that in a sprint run. That's production knives. As for customs, sounds like you need to speak to Danbo if you want something in CPM-D2. From what I know of his work, you wont be disappointed!

 

[Burdan]

Based on this chart, 440C is better than D2 and 154CM. It looks like s30v is only slightly better than 440c. Is this true?

and:

....
By that statement you are implying that one cold take a knife made out of pot metal and it would hold an edge forever....

Hi guys, sorry to interrupt, but I had a quick question regarding a chart that was posted by Mastiff.

I was surprised to see where 440c landed on the chart, above 154cm and D2. Do you guys know of another inexpensive steel (relative term, i know) that outperforms other more expensive blade steels?

And.... has Bob Dozier tried to work his magic HT on CPM-D2? I have never experienced it, but I hear Bob Dozier can turn D2 into a super steel. I know they are different steels, but i thought i would ask.

 

[Noctis3880]

Hi guys, sorry to interrupt, but I had a quick question regarding a chart that was posted by Mastiff.

I was surprised to see where 440c landed on the chart, above 154cm and D2. Do you guys know of another inexpensive steel (relative term, i know) that outperforms other more expensive blade steels?

And.... has Bob Dozier tried to work his magic HT on CPM-D2? I have never experienced it, but I hear Bob Dozier can turn D2 into a super steel. I know they are different steels, but i thought i would ask.

I doubt the accuracy of that chart, though it could be possible if all steels were at the same hardness. I don't recall ever seeing 440C higher than Rc 58, and D2 is typically found around Rc 60-62. So perhaps 440C would outperform D2 if both were at Rc 56, but D2 is typically never seen below Rc 60 and should have better performance.

From what I can tell, Dozier never made a knife out of CPM-D2. It might be because that version doesn't heat treat like regular D2 or because he felt the improvement wasn't enough to justify the cost.

 

[Burdan]

...
From what I can tell, Dozier never made a knife out of CPM-D2. It might be because that version doesn't heat treat like regular D2 or because he felt the improvement wasn't enough to justify the cost.

Do you think maybe he is really using CPM-D2?

if i made blades for a living, i would probably shorten and abbreviate a lot of words too. and i could see a knife maker get asked the same question a million times a knife show "what steel is this" and i could easily see a knife maker say "Its a D2 steel". i imagine he would get tired trying to explaining to people what CPM really means every time the question was asked.

you could see how this could be easily miss-communicated?

 

[Artfully Martial]

I'm pretty new to knives, so if you knife geniuses could simplify it, how does CPM D2 rank? I used conventional D2 for years in like 10 Benchmades and loved it. I haven't really gotten to see what it can do in my tyrade(s) because I love them too much to beat the hell out of them.

Outside of rust resistance, out of curiosity, how does it compare to S30V @ RC ~ 60?

 

[Noctis3880]

I'm pretty new to knives, so if you knife geniuses could simplify it, how does CPM D2 rank? I used conventional D2 for years in like 10 Benchmades and loved it. I haven't really gotten to see what it can do in my tyrade(s) because I love them too much to beat the hell out of them.

Outside of rust resistance, out of curiosity, how does it compare to S30V @ RC ~ 60?

Ankerson puts it in the same category as S30V at Rc60. Going out on a limb, I'd say S30V is tougher and holds a razor edge longer(due to smaller and harder carbides), but the CPM-D2 will be slightly easier to sharpen.

 

[Tony8179]

I've got an Active Duty framelock from Pat Nihiser in CPM-D2 so I guess he works with it. I've also seen a couple Eric Elson Outdoor Dreadlocks in CPM-D2 so I would assume that he also works with it. This, of course, is if you're looking do go down the custom road.

 

[The Mastiff]

I was surprised to see where 440c landed on the chart, above 154cm and D2

Burdan, I'm not sure about the results. 440C is a good steel, pretty wear resistant and corrosion resistant but known to get chippy and not have especially great edge stability especially at higher hardness. As far as which steels were tested at what hardness, I have no idea.

Chrome carbides are the primary in 440C. Moly carbides are the primary in 154cm. They are smaller and harder than chrome carbides and I would have thought that 154cm would have better wear resistance , both abrasive and adhesive than 440C. This shows I sure don't know it all.

Carpenter is making a powder version of 440C which will supposedly do for 440C what CPM 154 does for 154cm. It's called CTS-40CP. I know Bark River did a small run of it but I'm not sure about any others yet. In a magazine article Dozier spoke highly of it.

Do you guys know of another inexpensive steel (relative term, i know) that outperforms other more expensive blade steels?

I guess the Sandvik steels 12C, 12C(M) , and 13C are probably closest to fitting your description. Some of the 10 series can be found for decent prices and they can be made to perform pretty well IMO. 1075, 1084, and 1095 have all performed well for me but here 1095 is probably the most common and easiest to get, followed by 1084.

Joe

 

[Ankerson]

and:



Hi guys, sorry to interrupt, but I had a quick question regarding a chart that was posted by Mastiff.

I was surprised to see where 440c landed on the chart, above 154cm and D2. Do you guys know of another inexpensive steel (relative term, i know) that outperforms other more expensive blade steels?

And.... has Bob Dozier tried to work his magic HT on CPM-D2? I have never experienced it, but I hear Bob Dozier can turn D2 into a super steel. I know they are different steels, but i thought i would ask.

Bob Dozier does a great job with D2, but no amount of HT and tempering will turn D2 into CPM-10V or CPM-S90V because the alloy content just isn't there to form the carbides.

D2 does have some Vanadium (.80%) Chromium (11.5%) and Molybdenum (.90%), but not really high enough to make a huge difference when comparing it to 10V and S90V.

 

[Big Mike]

From what I can tell, Dozier never made a knife out of CPM-D2. It might be because that version doesn't heat treat like regular D2 or because he felt the improvement wasn't enough to justify the cost.

IIRC, Bob did make some test blades in CPM D2, but I have not seen any of his "production" knives offered in this steel.


Bob's D2 is some of the best blade steel I have encountered, his HT seems to optimize edge retention.

In my testing, the only steel that has shown better edge retention is CPM M4 on my Spyderco Mule, but's that's just my opinion.




Big Mike

 

[Lycosa]

Just wait till CPM Rostfrie comes out. Watch out INFI and every other steel!!

 

[The Mastiff]

Big Mike, did you get to work out one of those CTS-40CP knives, or did I imagine them?

Joe

 

[Ankerson]

IIRC, Bob did make some test blades in CPM D2, but I have not seen any of his "production" knives offered in this steel.


Bob's D2 is some of the best blade steel I have encountered, his HT seems to optimize edge retention.

In my testing, the only steel that has shown better edge retention is CPM M4 on my Spyderco Mule, but's that's just my opinion.




Big Mike

You bring up a really good point here, one that hasn't really been pointed out yet in this thread.

Bob Dozier is a custom knife maker and he does his own heat treating, that can make a huge difference.

There are also other Custom knife makers out there that can heat treat for optimal edge retention using other steels than D2.

Even given that companies like Spyderco tend to have their steels heat treated for optimal performance.

This gets into a whole new discussion on HT, blade geometry, edge geometry, knife design etc. These matter too and can all make huge differences in how a knife and steel can perform.

Take a Custom blade in CPM-S30V that is heat treated and tempered for max edge retention to 62 HRC, grind that blade really thin with .010" behind the edge on a flat ground blade optimized for cutting.

That blade would perform like most would never dream of and blow away most production blades.

Take those same specs and use D2, M4, S90V, S110V, 10V or a lot of other steels HT and tempered for max edge retention and we would get the same results.

Now take those blades and compare them to each other directly and we will see a different story.

Understand were I am going with this?

 

[Yarivan]

Hola
Guys I do not have so much expereince as you in knives and steels used.
But I have read the testing of Microtech Socoms in D2 and S90V by some Russian knife crazy guys. They were also very surprised when the D2 showed better results than s90v. Taking into consideration how much these knives cost in Russia (USD 500-600 +) I can understand them.
Personally I like Boa in s60v very much. Even I do not understand the difference between edge holding and wear resistance as you
but I am pretty sure that this steel is better than s30v

Will try to kill the edge on my composite leek tonight - have a lot of cartons in the office. Will report tomorrow.

By the way 440C is very good steel. My Harley -Davidson LFK is used very hard when we go out of the city. Performs great (good lenght and perfect handle) but the edge stays ok. I do not sharpen it more often than Spec Bump or Subrosa

 

[Artfully Martial]

I've actually always felt 440C was underrated...

 

[Big Mike]

Big Mike, did you get to work out one of those CTS-40CP knives, or did I imagine them?

Not the CTS-40CP, but Mike Stewart did make one of his prototype CTS-XHP Woodland Specials available to me.


I did some edge retention testing when I first recieved it,

...and have been using as a job-site EDC quite a bit the last few months.



I am very impressed with this steel, like Bob Dozier's D2, this steel just keeps on cutting.


I do have two CPM S30V customs, one at 59Rc and the other at 61Rc;

...the edge retention on the CTS-XHP was a bit better,

...plus it was much easier to sharpen then the S30V or the D2.


I also got to test one of Bark River's CPM S35VN Highland Specials,

...I found the edge retention and ease of sharpening similar to the CTS-XHP.


As discussed on the Forum, the CTS-XHP does not seem to be available,

...I know Bark River has started to aquire CPM S35VN to use as it's premium stainless steel on many of it's models.


Not having a big need for stainless steel knives, I tend to favor CPM 3V and CPM M4 as premium knife steels.




Big Mike

 

[lionknife]

I'm a big fan of D2 in general, but I have heard some great things (anecdotally) about the CPM D2 steel in particular.

So what makers are putting out knives in CPM D2 currently?

Boker does on their Dozier Boker fixed blade bo611 . Oh Oh , forgot i entered this post , and entered it again later , getting old i guess.

 

[Big Mike]

You bring up a really good point here, one that hasn't really been pointed out yet in this thread.

Bob Dozier is a custom knife maker and he does his own heat treating, that can make a huge difference.

There are also other Custom knife makers out there that can heat treat for optimal edge retention using other steels than D2.

Even given that companies like Spyderco tend to have their steels heat treated for optimal performance.

This gets into a whole new discussion on HT, blade geometry, edge geometry, knife design etc. These matter too and can all make huge differences in how a knife and steel can perform.

Take a Custom blade in CPM-S30V that is heat treated and tempered for max edge retention to 62 HRC, grind that blade really thin with .010" behind the edge on a flat ground blade optimized for cutting.

That blade would perform like most would never dream of and blow away most production blades.

Take those same specs and use D2, M4, S90V, S110V, 10V or a lot of other steels HT and tempered for max edge retention and we would get the same results.

Now take those blades and compare them to each other directly and we will see a different story.

Understand were I am going with this?

I am totally with you on this, :thumbup: :thumbup:

...and have always believed that finding a talented knifemaker is much more imprortant then stressing over steel selection.




Big Mike

 

[nozh2002]

You must have missed the part of the class that laid out the distinction between internal validity and external validity of experimental results. An experiment can have high internal validity (results that are consistently obtainable under the specific conditions used) but low external validity (fails to generalize across a range of different conditions/situations).

Let's assume, for the sake of argument, that your experiment has high internal validity. The only conclusion that allows us to draw is that Steel X is better that Steel Y at cutting manila rope (under the specific test conditions you used, and the specific metric for "better" you used). It doesn't at all warrant the conclusion that Steel X is better than Steel Y in general (i.e., across a range of conditions/tasks/metrics) -- in other words, that the study has high external validity. And this is exactly the inferential leap you're making when you pop up in every steel thread using your experiment to make blanket statements that one steel is better than another.

All what you say may be very well true, if it has some test results which is different then mine, and I really like to see that. However so far there are no other test available around. So until then this is just baseless words, any one can generate (and many do here obviously).

Do you have other research with testing done which may support your claime on inferior external validity of my tests? Show them if you have. If you don't - why bother talking about that? Everything is possible in theory - this is power of imagination, but I am doing real testing, sorry.

Now unexpected finding I was mentioned already had external validation - please, pay attention to my previous post - they are there. And I have more cases like that.

Thanks, Vassili.