Would CPM9V make a good blade?

hardheart said:
HC is high carbon, a little over 0.1% extra. There is also a high sulfur (HS) version for easy machining. 3V can be run harder, but toughness drops off considerably from the peak of ~85 ft lbs at 58. PM M4 is actually tougher once you get over 3V 61, and HC is also tougher if you get over 62, roughly. Comparing charpy is not exact, but what we have.
Click to expand...

Any production knives in HC M4? That's quite interesting.
 
So now I have a decision . I can only afford 1 custom this year or next for that matter. I need to determine which provides the most ROI as I have decided it will be one of 3 steels - S90V, Elmax, M4

Now to find a maker here that works with these steels. So far I think it will be a different maker for each steel.
 
I know you want a custom, but Spyderco recently released a production version of Phil Wilson's Southfork model.

It might be a cheaper way for you to try out some properly heat treated S90V in a very proven Phil Wilson design.
 
Ankerson said:
cpm s110v, cpm s90v, cpm 10v, k294, k390, m390, cpm 154, cpm m4.....

Read this article. :)
http://www.seamountknifeworks.com/articles/montecrito no 2how_long_will_an_edge_last.pdf
Click to expand...

"How long will an edge last? Depends on the user, what he is cutting, how the blade is
ground and sharpened, the hardness and the steel grade. Pretty much in that order I think.
It also very much depends on how fussy you are about sharp."
I like the first start of it..
I highly recommend reading this article..
 
Great articles there. :)

I re-read them regularly to glean things I missed before. I'm thinking my next custom is either going to be one of the A11 steels (Rc 63ish) or M4 pushed way up there (Rc 64-65+) The bending fracture strength of that steel is incredible...

And while I agree with Hardheart about 3V dropping way down compared to itself, its still way up there compared to many other common blade steels in terms of charpy at RC 61+... if I want a chpper type knife I'd go with 3V over other steels and run it just a little less hard.

That said I use my knives for cutting not bending, twisting or prying so my use may be different than others.
 
Last edited:
I looked at getting the Spyderco Phil Wilson model but by the time I rehahandle it (arthritis blows) i will be in over $300. This should be about the cost of a custom and the Spyderco looks very thin
 
RWT said:
I looked at getting the Spyderco Phil Wilson model but by the time I rehahandle it (arthritis blows) i will be in over $300. This should be about the cost of a custom and the Spyderco looks very thin
Click to expand...

Thin is in, my man. The Southfork is a very aggressive cutter for a production knife due to it's thin and honestly, excellent geometry. Probably won't like stabbing bricks, but man does it cut and slice!
 
Rapt_up said:
sharpness is lost one of three ways...
1) wearing down the edge
2) chipping the edge
3) bending denting or flattening the edge

1) is fixed ny choosing a high wear alloy with lots of carbides
2) is fixed by choosing a steel with high toughnes or by heat treating it to a lower hardness
3) isfixed by making the blade harder.
Click to expand...

I'm going to offer a slightly dissenting opinion on these 3, and add a #4) Corrosion. I've had the edge of one of my kitchen knives dull noticably while cutting some acidic food, apples, grapes, onions, lemons, etc. Unknown carbon steel blade, so it's a reasonable expectation, but still, it lost a nice crisp edge pretty quickly.

1) IMO, wear is the least of these three. I've cut quite a bit of cardboard with an annealed 1095 blade, and the edge would steel right back into place for a while. It will eventually take over as the primary dulling mechanism, but only after 2 and 3 have made the edge thick enough that deformation stops.
2) chipping happens from impace, in which case high toughness helps. But it also happens from slow lateral loads, in which case toughness doesn't help much. Think of the brass rod test. If you push hard enough, any blade hard enough to hold an edge will chip. It's an odd thing, but a higher hardness, lower angle, thinner edge will deform more before chipping than a soft, thick, obtuse one.
3) Completely agree. High wear, relatively soft steels just dent/roll, loosing sharpness. I'm talking about high levels of sharpness. They'll keep cutting for a while, but it's not the same as if the hardness were high enough to keep a crisp, sharp edge. For this reason, I typically avoid very high wear steels with hardness below 60 HRc.
 
Have you called or e-mailed Phil Wilson? He sounds like the go-to guy for what you're looking for. I'd love to have an excuse to get him going on about these steels.
 
I took a look at CPM 9V years ago and came to the conclusion if I wanted a tougher high vanadium grade that I would just temper CPM 10V back to the upper 50'S RC. That did not work very well, but 10V at 60 is a compromise that works ok. However I miss the crisp cutting that the harder edge provides. I guess I would say 9V and 10V at the same hardness (56-58) are pretty much the same steel except 9V has less vanadium carbide. Phil
 
Phil- thanks for the input and even more for the time you put in working the steel. I really enjoy the articles on your sight and since you hunt and use your blades in the same manner I do; I have faith in your findings. I doubt I clean as many bison or elk as you do, but I make up for it in hogs. If you are ever around Austin, look me up. You are invited to take as many as you want. The Spyderco model is still on my list of wants.

I decided on Elmax as my first custom to see how it will hold up, just waiting on the comission check to make it a reality.
I'll give it a full year of testing before making a decision on the next steel.
 
RWT, Thanks for the invitation to hunt hogs. If diesel were $2 per gallon I would leave tomorrow. Hogs are the ultimate test on edge holding in real life. You already know that and is why you are looking for a steel to do the job. It is kind of like one hog equals one bison or elk. I will be interested in how what ever you end up with works. ELMAX is a good choice since the vanadium carbides will give good wear resistance and it is stainless. If you go with a custom shoot for RC 60 in that grade. Phil
 
Phil, I hear you on the fuel cost. We just put up 3/4 mile of fence in 3 days and the diesel alone to clear the old fence and brush ran us $200. Sad thing is diesel should be less than gas as it is less costly to refine the fuel.

I'll ask the maker to go 60 RC based on your recommendation. Here is one that did not get away. So far this year between three of us we have shot over 36 hogs and that is only hunting about half of the time. We just run into them working cows and foodplots.
passaround3022.jpg
 
Totally agree with corrosion as a 4th cause.

In response I didn't mean to imply the order was in terms of most to least signfiicant... Indeed the significance is tied to how one uses their knife.

Toughness is both for high and low speed side loads toughness reduces chipping in both cases. And yes side high hardness high strength and toughness super steel will flex far more without chippng of damage than a lower grade of steel or even the same one at a lower hardness... For me deform imples a permanent "bending" of the metal. Deflection is springy change that returns to where it was.

me2 said:
I'm going to offer a slightly dissenting opinion on these 3, and add a #4) Corrosion. I've had the edge of one of my kitchen knives dull noticably while cutting some acidic food, apples, grapes, onions, lemons, etc. Unknown carbon steel blade, so it's a reasonable expectation, but still, it lost a nice crisp edge pretty quickly.

1) IMO, wear is the least of these three. I've cut quite a bit of cardboard with an annealed 1095 blade, and the edge would steel right back into place for a while. It will eventually take over as the primary dulling mechanism, but only after 2 and 3 have made the edge thick enough that deformation stops.
2) chipping happens from impace, in which case high toughness helps. But it also happens from slow lateral loads, in which case toughness doesn't help much. Think of the brass rod test. If you push hard enough, any blade hard enough to hold an edge will chip. It's an odd thing, but a higher hardness, lower angle, thinner edge will deform more before chipping than a soft, thick, obtuse one.
3) Completely agree. High wear, relatively soft steels just dent/roll, loosing sharpness. I'm talking about high levels of sharpness. They'll keep cutting for a while, but it's not the same as if the hardness were high enough to keep a crisp, sharp edge. For this reason, I typically avoid very high wear steels with hardness below 60 HRc.
Click to expand...
 
Tag up 6 more hogs since Saturday - 2 of them are running away with $25 worth of arrow and broadhead
 
You must log in or register to reply here.
Back
Top