What is "CPM", and does it make a difference?

bld522 said:
The issue isn't as much around the use of the letters "CPM" as it is the use of the letters "CM". If the designation for a 154-based steel has a "CM" following it, I assume it's 154CM regardless of whether the letters "CPM" precede it or not. If the designation for a 154-based steel starts with "CPM" but does NOT have the letters "CM" following it, I assume it's CPM-154. Or to put it more simply:

154CM = 154CM
CPM154CM = 154CM
CPM154 = CPM154

Having said that, I don't like to make assumptions, especially when there's so much confusion about the different designations. If you're in doubt, I'd suggest you contact the manufacturer of the knife and ask them which alloy their using.
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Are you sure about the second equation?
 
bld522 said:
The issue isn't as much around the use of the letters "CPM" as it is the use of the letters "CM". If the designation for a 154-based steel has a "CM" following it, I assume it's 154CM regardless of whether the letters "CPM" precede it or not. If the designation for a 154-based steel starts with "CPM" but does NOT have the letters "CM" following it, I assume it's CPM-154. Or to put it more simply:

154CM = 154CM
CPM154CM = 154CM
CPM154 = CPM154

Having said that, I don't like to make assumptions, especially when there's so much confusion about the different designations. If you're in doubt, I'd suggest you contact the manufacturer of the knife and ask them which alloy their using.
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Oh WTF!?!
 
kreole said:
Are you sure about the second equation?
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Sure enough not to assume that a knife that says CPM-154CM is constructed of CPM-154.

Look at the data sheet, boys and girls:

http://www.alphaknifesupply.com/Pictures/Info/Steel/CPM154-DS.pdf

Does it say CPM-154 or CPM-154CM? Is there anything anywhere on that sheet that refers to the alloy as CPM-154CM? Does Crucible even manufacture an alloy that they themselves refer to as CPM-154CM? If not, where did the term "CPM-154CM" come from and which alloy is it supposed to represent, 154CM or CPM-154?

You tell me.
 
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The kershaw steel chart(not all the charts say the same) doesn't have a distinction. On the blur they put cpm 154. On the ZT 0200 154cm. I wonder if their the same steel regardless of the labeling.
 
there is 154CM and CPM154, nothing else. The CM is actually a throwback to Climax Molybdenum, who originally developed the alloy.
 
rbmcmjr said:
And yet the quote in this post: http://www.bladeforums.com/forums/showthread.php/389030-Cpm-154?p=3730013#post3730013 indicates that in 2006, CPM154CM was how Crucible was marketing what is now known as CPM154.
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Good find, rbmcmjr. It appears that Crucible was using CPM154 and CPM154CM interchangeably in 2006 but decided in favor of CPM154 in order to prevent confusion. Perhaps that's why there's no current Crucible literature describing CPM154CM. As hardheart said, there's 154CM and CPM154, nothing else.
 
bld522 said:
Good find, rbmcmjr. It appears that Crucible was using CPM154 and CPM154CM interchangeably in 2006 but decided in favor of CPM154 in order to prevent confusion. Perhaps that's why there's no current Crucible literature describing CPM154CM. As hardheart said, there's 154CM and CPM154, nothing else.
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Unfortunately some companies still sell CPM154 as CPM154CM, so it's not quite that simple.
 
kreole said:
Unfortunately some companies still sell CPM154 as CPM154CM, so it's not quite that simple.
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I know Admiral has the mistake, but Admiral also sold 8670M as L6 for years before their customer complaints got them to fix the error. Any other companies who couldn't catch up to a five year old issue? :D
 
Yep. For my part, I will never buy a "CPM154CM" knife without checking to be sure it's made out of CPM154 rather than 154CM.

Caveat emptor.
 
bld522 said:
Yep. For my part, I will never buy a "CPM154CM" knife without checking to be sure it's made out of CPM154 rather than 154CM.

Caveat emptor.
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And, you'd be missing out on good knives. CPM154CM is the exact same steel as CPM154; NOT 154CM. The people who list the knives as CPM154CM are simply being redundant.
 
Not to worry, Danbo. I'm pretty good at using telephones and e-mail. ;)

Problem is, long before there was a "CPM154", some knifemakers were referring to 154CM as CPM-154CM. Why, you ask? Because "Crucible" and "CPM" are often used interchangeably when in fact, they are not the same. Say what you will, but I'm just not willing to run the risk of buying a "CPM154CM" knife constructed of 154CM when I assume it's made out of CPM-154. IMO, there's just too much room for error. YMMV.
 
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I don't recall ever seeing any knifemakers using 154CM and calling it CPM154CM. Who did that, if you don't mind me asking?
 
bld522 , yes that's right . But in use there is a difference between CPM154 and 154CM .The CPM grade is significantly better and my favorite all round steel [ until CPM S35VN came along !!! ]
 
Exactly. That's why I don't trust that the name "CPM154CM" represents CPM-154 and I never will.

Just so we're clear, the fault for all of this confusion has to be laid at Crucible's doorstep. All they would have to have done is changed the name of CPM-154 slightly to solve the problem. Something as simple as CPM-154A would have fixed it. But instead, we're left with a naming convention that will undoubtedly cause controversy for time immemorial.

PS: I'll be keeping this thread in my subscribed threads. Unless I miss my guess, I'll have to refer to it often.
 
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kreole said:
If you search our own custom makers' forum, there are a ton of results. The latest, as examples, are http://www.bladeforums.com/forums/showthread.php/898319-BBK-Textured-Digi-Camos?highlight=CPM+154CM and http://www.bladeforums.com/forums/showthread.php/860508-SOLD-3-1-2-quot-trapper?highlight=CPM+154CM
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What would make you suspect that these blades aren't CPM154? Just because they have CM at the end? Looking at those descriptions, I would have zero suspicions that the blades weren't the CPM version. ???
 
Danbo said:
What would make you suspect that these blades aren't CPM154? Just because they have CM at the end? Looking at those descriptions, I would have zero suspicions that the blades weren't the CPM version. ???
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Ack sorry, I misread what you said as using CPM154CM to refer to either, not specifically 154CM. My mistake.
 
To answer the original question.....No. I have them all and I cant tell a difference.
 
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