CPM M4....

M.Olexey

M.Olexey

Well-Known Member
Hey everyone.

I got a piece of CPM M4. I know nothing about it.

Trying to decide what to make out of it. What is it's claim to fame? What does it do best?


Thanks!
 
It has excellent edge strength and really good toughness at higher hardnesses allowing for sharpening at a smaller angle while maintaining stability. It is used often in competition cutting so it can excell in large blades as well as small. Just to give you an example I've heard of some people taking their smaller blades up to or past 63 and I believe the spyderco folder is around 65. I've heard of people taking come of the comp blades up to 61... I have some but haven't used it yet.
 
How big is the piece? I'd make something as big as the stock will allow! :)

Seriously, if it's very thick, I'd make as big of a chopper as I could. That's just me, though.
 
FOS Bali....you are on the list :unsure: :confused: :D

Not real big. About 2X11 and .225 thick.

J.Rosa, so if left in the low 60's with a normal edge thickness would it be much tougher D2 or A2?
 
D2 Yes. A2 not so much. A2 is just a small bit tougher but I doubt the average user would be able to tell the difference. CPM M4 would kill either as far as wear resistence though and noticeably so. Also, keep in mind it isn't stainless.
 
M.Olexey said:
FOS Bali....you are on the list :unsure: :confused: :D

Not real big. About 2X11 and .225 thick.

J.Rosa, so if left in the low 60's with a normal edge thickness would it be much tougher D2 or A2?
Click to expand...

Sweet! 2thumbs huh1 :unsure:
 
As I understand it, don't plan on doing anything to it after HT.... It's supposed to be a monster after HT!
 
I had heard post HT it was a bear to work.

Wear resistance is insane. Has to be hard to resharpen.
 
I have not tried it for a knife, but the parts I made for work were terrible to grind after HT. Lost more grinding wheel than I ground from the part. Great wear resistance compared to same part made from D2. Good luck.

Joe
 
MO,
I've been using CPM 3V lately. Not to bad to grind (easier than S30V) and I'm getting a great finish on it. The wear resistance is real good, and the impact resistance is excellent. It's my favorite knife steel if you don't care about the corrosion resistance. I etch it in ferric chloride to get rid of the carbon the surface.
-John
 
I just picked up some 3V based mainly on posts I've seen about it from you and Jerry. I prefer carbon steels so corrosion resistance is not a big deal. I'm looking forward to making some knives out of it.
 
Les George said:
As I understand it, don't plan on doing anything to it after HT.... It's supposed to be a monster after HT!
Click to expand...

It is!!!! A sharp 220 grit belt and then followed by a scotchbrite belt works as good as you will find when tempered. It is not all that bad to sharpen, but it is expensive. It does do a great job on edge retention.
 
just finished my first m4 knife a hunter, grind it thin it can handle it the one I made was 5 thous. before HT and you better have everything done before Ht because your not gonna grind it after, for a chopper go about 15 thous.
 
I compete in bladesports competitions and run my M4 cutter at 61. My EDC is about 63. Grind it thin and use diamonds to sharpen and it is not bad. My comp. cutters are ground at about .016" and my edc was ground at .005". The first hunter size I made I took to .010" and it held up fine, so I took the second one to .005" it has also held up well. Still carrying it after 2 years, will be making me another one soon. I highly recommend finishing before HT. All you want to do after HT is remove the oxidation. Mirror finish is next to impossible.
 
In the annealled condition it is easy to work with, in fact easier to grind than some of the A2 I've worked with. When hardened it eats up belts. My only abrasive that can grind it well is my Cerpass XTL based belt.

I'm getting black rust spots on it but the rust doesn't grow. It doesn't get pitting rust or any sort of deep rust. It doesn't rust the same way as carbon steels.
 
You must log in or register to reply here.
Back
Top