Is CPM-440V the holy grail?

[Uncle Bill]

Looking at some of the things being said about this stuff, it sounds vastly superior in edge holding and other characteristics. What do you knife makers think? What's the "rest of the story"? Will everybody soon go to this steel, or will there always be reasons to keep doing blades in ATS-34, 425, 1095, etc?

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I don't want my children fed or clothed by the state, but I would prefer THAT to their being educated by the state.

 

[David Williams]

I thought Talonite and INFI are a step above that. And where does BG-42 fit in? I'm still learning myself.

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"A knifeless man is a lifeless man"
-Nordic proverb

 

[SDMatteson]

As far as factory blade steel is concerned ,
440v is by far the best that I have used .
420v is better , but is not available in
production knives . 440v lives up to the hype given ats34 . I used 440c for years and
was excited when ats 34 became widely available.I expected a big improvement that
never showed up untill my neighbor delivered
the Military that the UPS man had left on his
doorstep by mistake .

 

[hankrearden98]

How does 440-V compare to AUS-8A?

 

[Don G]

My Spyderco Military in 440V is a fantastic knife. The edge holding is amazing.

I don't think there is a holy grail of steels. I think a lot of it has to do with tradeoffs (toughness vs. edge holding, etc.) and how well the maker does the heat treating and edge grinding. Different makers swear by different steels but I'm sure that the best makers can get excellent performance out of any of the best steels (ATS-34, 440V, 3V, O1, 52100, A2, D2, etc.) based on the work they put into it.

 

[Cliff Stamp]

While I have no direct experience with 440V, from the material properties I would not rate it as one of the better steels for knife blades. The primary reason is that the impact toughness, based on CPM's own spec sheets, and thus it is often left rather soft. There are lots of people who are using it though and are satisfied with its performance.

-Cliff

 

[memnoch]

i thought the ranking was like this:

CPM 420v
CPM 440v
BG-42
vg 10/ats 34/ats 55

 

[Oregon Duck]

As long as there are different job or mission requirements for knives there will be no one steel across all knife types that is best suited to all possible missions or jobs. All steels are born of compromise and there is no getting around this rather elementary fact.

Some people need toughness over edge holding, some people need lack of corrosion over toughness, some need non magnetism at all costs. After all, do you have just one screwdriver, or drill bit, or wrench?

Show me the man who would use just one type of tool or material for all possible circumstances and I'll show you a man who doesn't think very often and doesn't appreciate finesse.

Try and get by for a while using a crescent wrench as your only wrench, hammer, prybar, and clamp and you'll gain an appreciation of why there will always be different knife materials and different blade profiles. Knives are tools and if you need one you really need many different ones for many different tasks. One future knife may just be the be all and end all of knife making, but it cannot help but disappoint some people because every knife and every steel is born of a compromise made somewhere along the decision making process.

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Necessity is the plea for every infringement of human freedom. It is the argument of the tyrant; it is the creed of slaves.

William Pitt, 1783



[This message has been edited by Oregon Duck (edited 30 September 1999).]

 

[Jeff Clark]

AUS-8 is a lot softer than 440V which might not be a disadvantage for a kitchen knife. If you need blade strength such as for chopping hard wood, cutting a few metal straps, or some incidental prying you want a tougher steel. For example cryo D2 or BG42 might be better.

My current folder pick uses 440V, but I may get one with BG42 instead. My hunting/camp knife uses BG42.

 

[Codeman]

I've got a BF BLue Native which is CPM 440V and a Busse #9. No question that modified INFI, and I assume INFI, is better. Now, I just wish I could get a Benchmade 710 and 705 in INFI.

Ray

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Knowledge without understanding is knowledge wasted.
Understanding without knowledge is a rare gift - but not an impossibility.
For the impossible is always possible through faith. - Bathroom graffiti, gas station, Grey, TN, Dec, 1988

AKTI Member #A000831

 

[Joe Talmadge]

Oregan Duck wrote:

>As long as there are different job or mission requirements for knives there will be no one steel across all
>knife types that is best suited to all possible missions or jobs

Totally agree. Witness just the differences of opinion on this thread. Some people love 440V and its edge holding. Others, like Cliff, want greater toughness, presumeably so he can put a thinner higher-performance edge on the steel, and he doesn't mind resharpening now and then provided he gets the performance.

For utility folders in particular, I used to strongly favor edge holding over toughness. But having chipped out too much ATS-34 and even Gin-1, I'm re-thinking my priorities. I've come to love super thin super high-performance edges, and I'm beginning to favor tougher steels provided I can take the edge thin. Edge holding is still important to me, but provided the knife can get through at least a weekend's worth of hard use without resharpening, I want toughness for that thin edge.

Bill, in my opinion, trying to come up with some definitive ranking for all uses and preferences is the wrong way to try to understand steels. For simplicity's sake you can come up with a list (memnoch's is a reasonable general list), but if you don't really understand each steel on the list, you can make pretty bad mistakes. Given Cliff's preferences, he might put 440C above every steel mentioned so far!

Joe
jat@cup.hp.com

 

[johno]

As others have said 440V and 420V aren't really the best choices for knife steel as they're low in toughness at common hardness levels. Good edge holding may be an acceptable tradeoff over toughness for some knives but the tradeoff should be advertised as such. Although lots of people have broken tips on plain steel knives over the years, usually trying to use one as screwdriver or for prying, some of the 'tactical' offerings in a brittle ATS-34 seem to be even a bigger problem, due to the asking prices if nothing else.

 

[JoHnYKwSt]

CPM advertises 420V to have excellent toughness as well as edge holding.

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Johnny
[]xxxxxx[]=============>

 

[Birdman]

Unless I'm reading it wrong, Crucible's web site is showing CPM440V discontinued.

CPM440V is dead. Long live CPM420V.

 

[johno]

Toughness and edge holding relative to what ? Per Crucible's 'Plastics Tooling Materials' page their 440C and 420V have the lowest toughness of all the steels listed but the wear resistance is very good for both. Per the 'Crucible Mold and Tool Steel Selector' page 440V has very good wear resistance but again very low toughness, even at Rc57, where it's less than half the toughness of 440C.

 

[JoHnYKwSt]

Johno,

Of course when I said that 420V advertises excellent toughness as well as edge holding, this is compared to other stainless steels.

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Johnny
[]xxxxxx[]=============>

 

[KenOnion]

The question to ask is what is the best steel for the type of knife. They are all excellent steels.
I doubt that you will need great impact resistance on your pen knife as you won't be choping with it in this case you would opt for a steel with great edge retention .Whereupon If you were to need a bush knife you would need a steel that can withstand the constant choping and twisting such as D-2 or m2 or 52100 or o1 or etc...
The goal here is to choose the proper steel for the task intended. there is a steel suited for every type of knife no one steel will do it all!
Hope it makes sence Aloha!!Ken


Punctuation only slows me down!