CPM m4 vs CPM cruwear

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Jan 23, 2017
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trying to find out as much as I can about these two steels. So far I understand m4 wins in edge holding and cruwear for toughness but would like to compare the two a little more and learn about these two. I think they would both make a perfect knife with a blade around 4 inches but just trying to figure out if these steels are as good as I've heard or if it's all hype.
 
I'm not going to be very helpful. I can vouch for M4 (one of my top two or three alloys); not the best in the wet but you probably know that. I have no cruwear.
Here's a link you may not know about :
http://www.bladeforums.com/threads/...ed-on-edge-retention-cutting-5-8-rope.793481/

Look at the larger list bellow the first list; it is more up to date and scientific.
Begining with : "Same method as above, but with a coarse edge, 400 grit".
 
I LOVE M4, I have 3 folders in it (GB and a Military) but no fixed blades, I just don't think it's a good choice for a fixed EDC user.

Competition knife sure, but not an EDC, it's just not tough enough in real life hard use. You could make it tough enough but by that time you'd be running it so far below it's max hardness what's the point of having it anymore?! If you want uncompromising fixed blade toughness AND wear resistance you want 3v or (this might come as a shocker) some good old A2.


Need to clean cut hanging 1" manilla rope? M4!
Need to slice and dice a line of 15 water bottles?
M4!
Every day yard or work tasks?
Not M4...
 
I believe cruwear is like an improved D2 looking at the CPM data sheets. It is also an air-hardening steel so it seems fairly similar.

https://www.crucible.com/eselector/prodbyapp/tooldie/cruweart.html

I don't know what m4 compares to, necessarily, as a reference point as it's suposed to be very wear resistant and take a very keen edge and keep it for a long time. It's low corrosion resistant and not as tough as something like 3V but I don't have first hand experience with it but I should have a bush/camp knife in it soon as it's almost finished at the maker's. M4 seems to be all about getting a nice edge and keeping it but it can be hard to get it.

Based on my experiences with D2, cruwear should be more rust resistant than M4 and M4 should be a little tougher in impact resistance. This of course depends on heat treat as either can be heat treated a little softer to improve it's toughness. In use, I imagine the ability to get a find edge on M4 vs the toothy edge cruwear favors (assuming it's like D2 here) and rust resistance are what will be most notable I think.
 
I LOVE M4, I have 3 folders in it (GB and a Military) but no fixed blades, I just don't think it's a good choice for a fixed EDC user.
Competition knife sure, but not an EDC, it's just not tough enough in real life hard use.

I think that depends on what the hard use entails. I have a Spyderco Manix 2 with M4 that I use for a work knife on weekends. I cut boxes and carve on 2x4s when I'm doing carpentry work around the house and it has no problem with that. But I've carried it in my pocket in the summer when doing yardwork and getting sweaty and it doesn't like that very much, it wants to rust too easily.

I think M4 is tougher than just about all stainless steels and plenty of fixed blade knives are made in stainless steel, even knives intended for "survival" use.

For really, really hard use I would agree that 3V, A2, O1, even Cruwear would be better. But I don't know how to easily define hard use. Competition knives do a lot of hard chopping through 2x4s and wood dowels, but no crazy lateral chopping or prying or batonning. For use around manmade stuff I have plenty of faith in M4. If I was going to try to tackle a forest I would use... a hatchet or axe or saw.
 
I have used both a bunch. I will share my impression through use. I have multiples of each from Spyderco.

M4 is more wear resistant and holds an edge longer and takes a little longer to sharpen.

Cruwear is dream to sharpen and in my estimation has edge retention on par with S30V.

Cruwear is not supposed to be stainless but it almost seems it in my uses. M4 is definitely not stainless and needs a bit more care than Cruwear.

They are both supposed to be tough steels and I have had no issues with either one chipping.

I hope this helped. :)
 
I have used both a bunch. I will share my impression through use. I have multiples of each from Spyderco.

M4 is more wear resistant and holds an edge longer and takes a little longer to sharpen.

Cruwear is dream to sharpen and in my estimation has edge retention on par with S30V.

Cruwear is not supposed to be stainless but it almost seems it in my uses. M4 is definitely not stainless and needs a bit more care than Cruwear.

They are both supposed to be tough steels and I have had no issues with either one chipping.

I hope this helped. :)
I have used both a bunch. I will share my impression through use. I have multiples of each from Spyderco.

M4 is more wear resistant and holds an edge longer and takes a little longer to sharpen.

Cruwear is dream to sharpen and in my estimation has edge retention on par with S30V.

Cruwear is not supposed to be stainless but it almost seems it in my uses. M4 is definitely not stainless and needs a bit more care than Cruwear.

They are both supposed to be tough steels and I have had no issues with either one chipping.

I hope this helped. :)
Yea all those comments helped and opened up more questions haha. I didn't know m4 would rust so easy I thought it would belle cruwear but that's good to know. I read someone wrote that cruwear was suppose to be on par with S30v.... I thought cruwear would of been way better from the things I have found but I guess everyone has a little different results.
 
I think CruWear can hold a much thinner(and cleaner) edge without sacrificing edge stability as opposed to S30V. One thing I noticed is how many people think S30V's a sort of low grade steel. While it does have faults in some areas, edge retention isn't one of them.
 
My comparison to S30V was not meant as a knock against it. Cruwear seems to take a finer edge a little easier and hold that fine edge a touch longer than S30V in my experience. I was mostly just referring to it being in a similar class of steels regarding edge retention along with XHP, CPM154 and Elmax. I consider that sort of the middle of the spectrum by today's standards and I think Cruwear falls in that range. I consider M4 to be on the next level above that along with steels like M390.

I like S30V and have never had the bad experiences many seem to have had. That said, Cruwear may be my favorite steel. Most steels involve some sort of compromise yet Cruwear seems to balance out all the attributes surprisingly well and is one of the most balanced steels I have used. If I could have only one folder it would likely be my Cruwear Military.
 
My comparison to S30V was not meant as a knock against it. Cruwear seems to take a finer edge a little easier and hold that fine edge a touch longer than S30V in my experience. I was mostly just referring to it being in a similar class of steels regarding edge retention along with XHP, CPM154 and Elmax. I consider that sort of the middle of the spectrum by today's standards and I think Cruwear falls in that range. I consider M4 to be on the next level above that along with steels like M390.

I like S30V and have never had the bad experiences many seem to have had. That said, Cruwear may be my favorite steel. Most steels involve some sort of compromise yet Cruwear seems to balance out all the attributes surprisingly well and is one of the most balanced steels I have used. If I could have only one folder it would likely be my Cruwear Military.

That wasn't directed at you, man. You didn't say anything bad about S30V anyway, haha. Hell, there's a variety of different blade steels I'd choose over S30V myself.

I was just trying to point out that nowadays people tend to see S30V as an inferior steel(and it is in certain categories), but it can hold an edge for a long time. CruWear seems to keep that "scary" sharp edge a lot longer than S30V. S30V tends to loses that "scary" edge relatively quick.

If anything a steel like CruWear being able to run with S30V is a compliment, haha.
 
That wasn't directed at you, man. You didn't say anything bad about S30V anyway, haha. Hell, there's a variety of different blade steels I'd choose over S30V myself.

I was just trying to point out that nowadays people tend to see S30V as an inferior steel(and it is in certain categories), but it can hold an edge for a long time. CruWear seems to keep that "scary" sharp edge a lot longer than S30V. S30V tends to loses that "scary" edge relatively quick.

If anything a steel like CruWear being able to run with S30V is a compliment, haha.

No worries, I was actually just trying to give some clarity to the OP in case he interpreted it different than I meant it. :)
 
No worries, I was actually just trying to give some clarity to the OP in case he interpreted it different than I meant it. :)
I honestly haven't been too impressed with s30v... only had it on a pm2 but the edge damaged very easy too me. Rolled and chip from normal cutting task every time. I sharpened it a few times and seemed to of gotten a little better but I quit using it.

I those videos were very helpful though. I'm real curious how tough m4 is. I like the sound of the edge holding and I'm not worried about the corrosion resistance so m4 might work out pretty good. I would be cutting would and all the normal camping/hiking stuff.
 
Here's a good visual comparison I was able to find on M4 compared to other, similar tool steels. The standard M4 isn't the toughest but the powdered metallurgy version is very tough, even at high hardness.

http://www.hudsontoolsteel.com/technical-data/steelC4

blockM4.jpg
 
Here's a good visual comparison I was able to find on M4 compared to other, similar tool steels. The standard M4 isn't the toughest but the powdered metallurgy version is very tough, even at high hardness.

http://www.hudsontoolsteel.com/technical-data/steelC4

blockM4.jpg
While I can appreciate the sentiment, I do have to say that I dislike charts like this.
A: Hot Hardness does not really matter when it comes to knives.
B: What is the scale? What is one if the horizontal bars measuring, one cut/chop 10, 1000?
C: How do they rank the alloys as comparable when they are differing hardnesses
D: when they don't state the geometry, what are we supposed to assume? Factory edge profiles?

It is well known that most factory edges can be prone to overheating of the apex and have some chipping issues. Once they are sharpened a few times and you get into better steel, it seems to resolve or partially correct this issue.
 
I honestly haven't been too impressed with s30v... only had it on a pm2 but the edge damaged very easy too me. Rolled and chip from normal cutting task every time. I sharpened it a few times and seemed to of gotten a little better but I quit using it.

I those videos were very helpful though. I'm real curious how tough m4 is. I like the sound of the edge holding and I'm not worried about the corrosion resistance so m4 might work out pretty good. I would be cutting would and all the normal camping/hiking stuff.

That's pretty much the opposite of what CruWear would do. Wear resistance and toughness are completely different aspects of steel. The only similarities between S30V and CruWear(as people have said), is roughly how long the edge will last.

CruWear is a damn tough steel, S30V isn't. Personally I wouldn't want S30V in a medium-large fixed blade that I'd abuse. It's geared towards cutting man made materials(cardboard, plastics, so forth).

To me CruWear is smack in the middle of toughness, wear resistance, and corrosion resistance. Between simple carbon steels and super PM steels. It's one of the few blade steels that can boast it has a good standing in all three of those categories.
 
While I can appreciate the sentiment, I do have to say that I dislike charts like this.
A: Hot Hardness does not really matter when it comes to knives.
B: What is the scale? What is one if the horizontal bars measuring, one cut/chop 10, 1000?
C: How do they rank the alloys as comparable when they are differing hardnesses
D: when they don't state the geometry, what are we supposed to assume? Factory edge profiles?

It is well known that most factory edges can be prone to overheating of the apex and have some chipping issues. Once they are sharpened a few times and you get into better steel, it seems to resolve or partially correct this issue.

A: Hot hardness doesn't apply to knives but since most steels aren't made exclusively for knives it's useful info for other end users.

B: They use CATRA method for testing wear resistance.

C: It's one vantage point to use as a reference guide. If they tested all hardness points and plotted out the layered scatter plot it would be less user friendly without a software attached.

D: It's about the steel not the profile. I assume CATRA has a standardized protocol.

As we know, there are many things that go into a blade's effectiveness for a given task other than just the steel. Everything pointed out about the dislike of the chart points out the limits of the charts but that doesn't make the information any less valid just that there are more things to take into consideration also.

When comparing a steel against another steel, and that's all, I find the charts reasonable to make general assertions on the differences. I trust the analytical information more than anecdotal evidence which can vary wildly. Doesn't work for everyone, as you've pointed out.
 
M4 is great from my use. Spyderco and benchmade don't use an optimal heat treatment like a lot of custom makers do, but its really good for a mass production knife. Holds an edge for a fairly long time depending how you sharpen it. Plenty tough too but never needed its toughness in a folder, but the edge has been really stable. I keep it oiled so it doesn't patina.

No comment on cru wear yet. Don't have any atm. Haven't really been too interested in it, but if I find a good deal or sale I'll try one out eventually.
 
One thing I noticed is how many people think S30V's a sort of low grade steel. While it does have faults in some areas, edge retention isn't one of them.

Yes if one looks at the Ankerson tests I posted S30V can be surprisingly good and durable TOTALLY DEPENDS ON THE HEAT TREAT and THE GEOMETRY. S30V is way up the list with "the good stuff".
And pretty far down the list if soft tempered and fat angled.
 
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