Military in CPM3V ?

[kwakster]

Am i the only one who would like to see the Military model made in CPM3V ?

As far as i know there aren't any folders from this steel out there yet, Spyderco can still be the first to make one.
Comparable edge retention to D2 and approaching the toughness levels of S7, looks like a killer blade material for the Millie in my book.
Even Jerry Hossom thinks 3V is great stuff.

What is the general opinion on this forum ?
:)

[JD Spydo]

I think this has been brought up before. I also think that there was a lot of demand for another Spyder in that steel.

However getting Spyderco to do a knife with a "non-stainless" steel is not going to be easy. Even though there has been one recently done in carbon steel it's not something that they do on a regular basis.

I'm a big fan of CPM blade steels myself and I really like the company. I think you're going to have better luck beating the drum for one to be done in Crucible's newer M-4.

Personally I think that they could use carbon steels and do well with them by simply coating the blades. The Boron Carbide that Bodycote uses is an excellent coating by all accounts I've been given. But with the mixed fanfare on coated blades and carbon steels I wouldn't bet any serious money on it.

[kwakster]

This is what Jerry Hossom has to say about CPM3V on another forum;

In my opinion, CPM-3V is the best knife steel ever.

It has the finest grain structure of any high alloy steel used in knives today, about 1 micron. That translates into extraordinary toughness and arguably as fine an edge as can be had. When you sharpen it, you don't have to cut through carbides, so it sharpens a lot easier than you might expect, certainly easier than S30V or even D2 IMO. I had a 3V knife at Rc61 destruction tested by bending it to 90 degrees, back and forth, four times before it finally snapped, and that blade was hollow ground which resists bending because of the geometry. 3% vanadium, coupled with extreme toughness to resist microchipping allows it to hold an edge a very long time.

The ONLY downside to 3V is its corrosion resistance which is pretty good but the nature of how it corrodes is annoying as hell if it happens. You do not get a smooth patina or a surface bloom of light rust. What you see IF it corrodes are some small orange spots on the blade, under which will be deep pits. This is likely due to minor oxide contamination in the steel, so I passivate all my 3V blades by etching them in 50% FeCl for about 10 minutes, before the final brushed finish is applied. This has ALMOST eliminated the problem, but I still recommend keeping a light coat of oil on the blade and have never had rust once a blade is etched and oiled. I use Birchwood Casey's Synthetic Gun Oil, which is a great protectant for any metal. 3V is about the same as D2 in this area, but benefits by taking a much finer finish than D2 so corrosion has fewer toeholds than with D2.

I put a fine finish on all my blades, but with 3V I always go to ~800 grit. All of my 3V blades, except swords, are hardened to Rc61.

Tough? In one test of one of my swords, the tester cut laterally through a shank of beef, including over 9" of meat and over 3" of bone without splintering the outcut on the bone and the only evidence of the cut on the blade was a very small (~1/8") flat spot on the edge, which had been sharpened to shaving sharpness. You couldn't see the flat spot from the side, only by looking down on the edge where you could see the reflection. That was a single-handed sword and just an amazing cut considering that beef leg bone is a VERY hard bone.

It's a great steel, and it's unfortunate that more people aren't familiar with it. It took a bit of a bad rap when it first came out because it is very sensitive to a well-controlled heat treating schedule, as is S30V for that matter, and some makers who tested it early on before that was well understood just didn't get what the steel had to offer. That's why I sold my heat treating oven and send all my steel to Paul Bos for heat treating.

I just read through this and guess this is as close to hype as I get, but the steel is a great steel and this is my experience with it. Just as an interesting side note, when I first started using this steel I told Crucible I was convinced that microchipping was a major component of knives going dull and that this steel would "wear" better than its component numbers might suggest because it was so tough. At the time CPM-10V was Crucible's super wear resistant steel. About 18 months later at the Eugene knife show, the top metallurgist at Crucible told me that they we finding that 3V was "outwearing" 10V in stamping dies. When they studied the reasons they discovered the 10V was microchipping and the hard, sharp edges were crumbling long before any abrasive wear could develop.

People in the woodworking industry have known about the toughness issue for a long time and many of the best woodworking tools are made with A2, which is a very tough steel. 3V is about 7 times tougher than A2, and I recently consulted with some people in that world who made some chisels and turning tools with 3V and found they cut better and longer than anything they had ever seen. AND BTW, they are also now putting convex edges on their chisels...

Try it, you'll like it.

[merciful]

... I'd sure like to try one!


This is what Jerry Hossom has to say about CPM3V on another forum;

In my opinion, CPM-3V is the best knife steel ever.

[JD Spydo]

Don't misunderstand me Kwakster. I would love to see 3 or 4 Spyders made with CPM S3V. I have nothing but respect for Crucible's blade steel. It is however going to take a vast amount of drum beating to get Spyderco to consider doing a blade with this steel.

Jerry Hossum isn't the only blade guru I have heard testify to how good that partcular steel is. I would give a pretty nickel to have a Gurkha Kukri made with that steel. I bet a hunting knife ( preferably with guthook) would be colossal with that steel.

That would also be a great one to bring back the G-10 Police with too IMO.

[Cliff Stamp]

Comparable edge retention to D2 and approaching the toughness levels of S7

These are not facts, though some makers have repeated them often, much of the above data cited from Hossom is of the same. The bending test was done in a piece of wood for example and the wood will just compress, do not use that to predict behavior of steel. I have bent VG-10 to 90 degrees in a piece of wood, that does not mean that is an exceptionally flexible piece of steel, the wood just deformed.

3V has moderate toughness compared to the really tough steels such as 3V, however it would be difficult to argue that shock resistance is needed in a folder anyway because if you subjected the blade to heavy shock it would be likely that the lock mechanism and or handle/blade join itself would be damaged.

In general comparing edge retention in such a general way is really misleading, the edge retention of D2 for example is actually very low if you are push cutting with fine edges and only high if you are slicing with coarse edges.

I would like to see a Military in 12C27M, there is no arguement I can see though to promote a high shock steel.

-Cliff

[KamSingh]

......3V has moderate toughness compared to the really tough steels such as 3V....


:rolleyes:

[EarthDog]

3V?

I would like it very much if Spyderco were to offer a fixed blade in this steel. At one time, I understand the plan was to produce the Schemp camp knife in 3V; however, the current plan (IIRC) is make it of H1.

I believe 3V would be an interesting choice for the second Mule Team knife. Bring it out, and have a lot of people test it.

[Cliff Stamp]

If the desire is to have a very fine edge which is very strong then there are any number of steels such as A2, 52100, O1, etc., which have that ability. How many people use such steels and complain about a lack of toughness? What would be interesting is to see if when 12C27 and 52100 were compared was there any actual advantage to 52100 because both have the same hardness and carbide structure and both with standard heat treatments will be very fine grained. There are a number of makers who would argue that there is no advantage and that steels such as 12C27 are just corrosion+ versions of the low alloy tool steels. There is some data such as gathered by landes which does support this, at least in regards to edge strength and verhoevens data supports it in regards to wear resistance, all that is missing is toughness comparisons.

-Cliff