s30v

[ChuckB_III]

from what i hear, s30v is awfully brittle, but then again variety is the spice of life, and these days if you want it, they probably make it if you look hard enough.

 

[josh48315]

so then what is a good tough steel for medium to semi large blades (4"-6") for outdoor/survival? like for chopping wood, cutting metal, hammering, pounding, prying, etc that wont break and can stay strong and sharp?

 

[Daniel Koster]

S30V is a great steel. IMHO, the very best stainless available. It is not "brittle".

But it would not be my first choice for impact strength. That would be 3V.





Jerry Hossom used S30V in many large knives. Frankly I'm surprised no-one mentioned it...*shrug*

 

[Michael.D]

so then what is a good tough steel for medium to semi large blades (4"-6") for outdoor/survival? like for chopping wood, cutting metal, hammering, pounding, prying, etc that wont break and can stay strong and sharp?

52100 (SR-101)
O1
A2
1095

 

[PatriotDan]

S30V is a great steel. IMHO, the very best stainless available. It is not "brittle".
But it would not be my first choice for impact strength. That would be 3V.

Jerry Hossom used S30V in many large knives. Frankly I'm surprised no-one mentioned it...*shrug*

mr. Koster, thank you for your comment. I too think that in stainless world it's very good. Unfortunately I believe your comment may fall on deaf ears as the very next thread about s30v is again going to bring up 10 user replies on it's "brittleness" and unsuitability to large and heavy use knives. Highly reputable blademakers using s30v in their heavy duty products seems to make no difference to that opinion.

 

[josh48315]

52100 (SR-101)
O1
A2
1095

i'm at the benchmade knife wizard page and went to lookup some fixed blades made of that steel and they don't have any of that steel for selection... http://www.benchmade.com/products/knife_wizard.aspx so as the newbie i am i am having a hard time believing any of the above mentioned steels are good for what i need.

 

[knarfeng]

i'm at the benchmade knife wizard page and went to lookup some fixed blades made of that steel and they don't have any of that steel for selection... http://www.benchmade.com/products/knife_wizard.aspx so as the newbie i am i am having a hard time believing any of the above mentioned steels are good for what i need.

Josh,

What do you need?
1) How big a blade are you looking for?
2) How are you planning to use it? What tasks? What conditions?

I should have asked these questions first.

 

[knarfeng]

First there is no guarantee that having it softer actually makes it tougher. The toughness dependance on hardness is usually highly nonlinear.

Second, the reason they have stated in the past for the lower hardness on S30V and A2 is ease of field sharpening on rocks and such. This is nonsense by the way.

-Cliff

Cliff, you said you had used the Green Beret with the lower hardness. I know you have also used blades with full hardness S30V and tested them extensively. What differences in performance, if any, did you notice with the lower hardness S30V? Did you notice a decrease in edge retension characteristics? I know it is difficult to compare steel using blades with different edge geometries, so I don't expect hard data. But I'm curious as to what your impressions were.

Knarf

 

[Jerry Hossom]

If S30V were brittle, why would I and a whole lot of other knifemakers use it?

I have to disagree with much of what Knarfeng said in the opening salvo. S30V was not optimized for edge retention. It was specifically developed as a stainless version of CPM-3V (a very tough steel). Edge retention is a great thing, but toughness in a stainless steel is a lot more elusive. If you want edge retention try S90V.

Can S30V have chipping problems? I've never seen it, but I guess it's true because people say so. Then again many of those same people say that when it's sharpened or resharpened properly the brittleness goes away. Was the steel brittle or was the edge stressed/chipped in production sharpening? It's my contention that S30V is at its best when the edge is fairly polished; it's also my contention that all steels are best with a polished edge. Some may disagree, but UNLESS you've actually used an S30V blade with a well finished edge, I don't think you're qualified to say the steel is brittle.

I think the reason you have trouble finding large factory blades in S30V is simply a matter of cost. The steel is expensive to start with, requires careful control of the heat treating process, and is not an easy steel to grind and finish by any means. Add to that the fact that people in here are going to bash it for being brittle, a company would have to be insane to want to bother with it. It would be a whole lot cheaper, easier and in the end more profitable to use...

52100 (SR-101)
O1
A2
1095

Unless of course someone really did want a high performance stainless steel that offered the best combination of corrosion, wear, and impact resistance of any stainless ever made.

 

[knarfeng]

I find my arguments overpowered by those whose experience is more extensive than mine. That is why I spend time here.

I bow to the East three times. I would erase the first post, but I consider that cheating.

Knarf

 

[Jerry Hossom]

There's no reason to withdraw what you've said, Knarf. You've generally expressed thoughts that are widely held to be true to many on the forum. Part of the problem here is that once something like "S30V is brittle" gets established, and it has, it becomes imbedded in the online spec sheet for that steel and causes a lot of people to miss out on a great knife steel.

There must be a sense there is a knifemaker S30V conspiracy to hype this stuff. I really can't imagine why we'd want to. It is miserable steel to work with (machining and finishing it is a b*tch) and a whole lot of other steels would be cheaper and easier to use. I don't know of any knifemakers who gain a competitive advantage by using a steel that is available to every other knifemaker on earth. Maybe we're just pig headed....

 

[Cliff Stamp]

If S30V were brittle, why would I and a whole lot of other knifemakers use it?

Because it sells. A statement is also not strengthened by repetition or numbers.

It was specifically developed as a stainless version of CPM-3V (a very tough steel).

That is absurd, if that was the case you would look at 12C27M or similar. Similar for non-stainless, if you want a tough steel then you reduce the carbon and carbide content to bare minima.

-Cliff

 

[Daniel Koster]

Your statement would seem to contradict "local lore", Cliff.


S30V sells because it is a high-performance stainless, not because knifemakers push it. It does everything a customer wants out of a stainless steel....good edge holding, good toughness, can take a polished edge, resists rusting. It's hard to imagine a better stainless steel.

More and more companies are using it too. Would you call their investment foolish?

 

[the possum]

Part of the problem here is that once something like "S30V is brittle" gets established, and it has, it becomes imbedded in the online spec sheet for that steel...

It was specifically developed as a stainless version of CPM-3V (a very tough steel).

No offense Jerry, but if Crucible's goal was to make a stainless version that retained 3V's toughness, they fell waaay short. Jeez- just look at their own spec sheets. S30V Spec Sheet According to their own data, S30V only has about 1/4 the impact resistance of 3V. That's a pretty darn big difference, wouldn't ya say? S30V may be tough compared to, oh, say, obsidian. But when you're talking about 3V in the same sentence, I think "brittle" is an accurate description, and it seems the folks who designed and made the steel might agree.

That same data sheet says S30V's toughness should be in the same league as other high carbide steels such as D2, 440C, and 154CM. This doesn't sound surprising to me.

 

[the possum]

More and more companies are using [S30V] too. Would you call their investment foolish?

If S30V were brittle, why would I and a whole lot of other knifemakers use it?

Less than one hour ago, two different co workers decided it was time to have their knives sharpened, and brought 'em to me. One had a Frost Cutlery lockback, and the other was a cheap barlow with stamped sheet handle covers. Both were duller than the table knife I used to spread butter on my pancakes this morning. Both "points" were wore down to rounded nubs. Thankfully the steel was so soft I was able to completely reshape them with my super coarse stone in 5 minutes.

Now, I'll bet you guys a dollar (hey, to a broke mofo like me, a dollar is a lot of money) that knives of this sort are carried in vastly more American working men's pockets than those in S30V or other "high grade" steels discussed here. But if these steels are "junk", why do so many people carry and use them?

 

[Daniel Koster]

simple: it's a matter of economics and ignorance.


As knife makers/buyers/sellers/traders/etc....we need to do a better job of educating the public and making quality products more readily available (note: I did not say cheaper )



You get what you pay for.


When people become more educated about knives (both custom and production) they are generally more interested in spending more. The value (both perceived and real) overrides economics.



Do I own some cheap-o knives...you betcha!

But for something I need to depend on...I go with better quality every time.

 

[Jerry Hossom]

Because it sells. A statement is also not strengthened by repetition or numbers.

And why does it sell? Because I say it's a good steel or you say it's a bad steel or because people who use it think it's a good steel and therefore knifemakers make what those people want? What vesting does a knifemaker have in using S30V? None! There is simply no incentive to use any steel that might exhibit inferior performance characteristics, especially one which is associated with higher costs to buy and process.

Does the fact that both the U.S. Marine Corp and Army Special Operations commands chose knives made in S30V over all other knives in other steels mean anything, or is that just some of that repetition and numbers thing?

That is absurd, if that was the case you would look at 12C27M or similar. Similar for non-stainless, if you want a tough steel then you reduce the carbon and carbide content to bare minima.

One of your problems Cliff is that you look at these things one parameter at a time. What good is "toughness" if the steel is so weak the edge rolls as soon as it hits anything hard? When carbon/carbide content is too low, as it is with 12C27M, the steel no longer possesses sufficient strength to resist heavy loads/impacts. It bends/rolls, and the first thing to bend/roll is the thinnest area, the edge. Bent/rolled edges are lousy cutters. There's also that issue of wear, since less carbon means lower carbide content meaning less wear resistance.

One of the reasons large cutlery companies use steels like 12C27, 440A or B, 420J2, etc. is because they are so weak they can be stamped from long rolls by automated machinery. Good steels like S30V, etc. have to be laser or waterjet cut from precut sheets in a MUCH more expensive process. Lesser steels are easier to grind and finish, and are more forgiving in heat treating and can be processed in much larger numbers. One of the reasons S30V wasn't used by knife companies for a couple years after it was introduced is because it is unforgiving in its heat treating needs. Large scale salt bath processing solved that problem. Most custom makers had to start using quench plates to get a fast enough quench to fully harden the steel and reduce grain growth and retained austenite. Some of us just depend on Paul Bos who has atmospherically controlled ovens and can rapid nitrogen quench to solve our problems.

I think I can safely say that if anyone in the industry thought 12C27 would have sufficed, nobody would have bothered with S30V. Are these lesser steels useful? You bet. They make good kitchen knives because they are stainless (virtually dishwasher safe), fairly easy to sharpen because of the reduced carbide content, and are less likely to break a point when they're tossed into the sink. They make serviceable but not great field knives for most of those same reasons, just don't expect to get a lot of mileage out of them in terms of heavy duty chopping, prying and cutting.

 

[Jerry Hossom]

The "design" goals of S30V were "a stainless tool steel as tough as A2 and as wear resistant as D2". A2 is a tough steel; D2 has excellent wear resistance; combining those virtues makes a very good steel, especially a stainless steel.

The discussion of what S30V was to be began with the desireability of a stainless CPM-3V. From that discussion, the more practical performance specs were defined.

Not many steels can compare with CPM-3V in terms of toughness under any conditions. I have tested several that had higher toughness numbers than 3V. All have failed due to plastic deformation, usually severe. That included two nonstainless steels with the same carbon content as 12C27M. These were S7, CPM-1V and M60S (stainless).

Here's a photo of what I mean about strength. The top blade is 154CM, Rc61, 0.030" behind the convex edge bevel. Bottom blade is M60S, Rc60, 0.030" behind the edge. Both edges were hammered through an 8d common nail.

(BTW, if tolerating being hammered through an 8d common nail isn't sufficiently tough for your needs don't buy 154CM either. Note, that was 154CM, not CPM-154 which is tougher. In a similar test with S30V, the edge was microchipped but it was virtually impossible to see from the side. It was however detectable by running a thumbnail down the edge. Easily repaired on a leather stropping belt.)

 

[Stainz]

I recently bought a Native S30V (W-M), simply because I was so impressed by the Cabela's special 'Alaskan Guide' version of the Buck Vanguard I had bought earlier. It's S30V fixed blade is 4.125" and has the black TiAlN coating, brass bolster & finger guard, and rosewood handle. Admittedly in the lower end of the required 4-6" knife, it is, at least thus far, a real beaut. It's sibling here, a standard Vanguard, is a great performer. While I don't hunt, and my knives do get little use, it developed the 'keeper' title here almost immediately - as did the 'AG' variant. Oddly, with an NRA coupon, the 'AG' Vanguard cost me the same as my standard Vanguard!

This S30V knife steel is alluring... I just ordered some Berry's Bullets from those folks... and the AG version of the Buck 110. What's the best way to 'polish' the edges of that steel - rouge-loaded strop, cotton buffing/polishing wheel, or?? Thanks!

Stainz

 

[the possum]

The "design" goals of S30V were "a stainless tool steel as tough as A2 and as wear resistant as D2". A2 is a tough steel; D2 has excellent wear resistance; combining those virtues makes a very good steel, especially a stainless steel. ...Not many steels can compare with CPM-3V in terms of toughness under any conditions.

They may have reached their wear resistance goals, but even if they were just shooting for A2 toughness they still fell short of their goals, from what I can gather on their spec sheets. Details are not given on the S30V sheet, but they say impact toughness should be around 25-28 ft-lbs. A2 at 60 Rc is 40 ft-lbs. L6 is a steel commonly used by bladesmiths, and the numbers I've seen on it place it at around 60-70 ft-lbs. I'd like to hear if you've seen L6 suffer from strength issues at 58 Rc or so.

BTW, if tolerating being hammered through an 8d common nail isn't sufficiently tough for your needs don't buy 154CM either.

No, it's not, and I don't. (at least on big knives) I've gotten nasty edge chipping from 154CM from chopping with a folder. It's kissing cousin ATS-34 broke when I used it on a big chopper.