S30V really an improvement over BG 42??

Gator97 · Apr 28, 2003

Originally posted by Cliff Stamp

Gator97 :
Yes, my point was that you need a comparison.
Well, yes, since originally(once S30V came out) I was trying to compare S30V and BG-42. However in this thread I was speculating about 58 HRC being optimum for S30V. Which is different from earlier data, on this forum and in others. Basically based on the statements here that some well known makers started lowering HRC to 58-59. If they've reached consensus on that, ok fine. But then I don't understand how it will be as tough as bg-42 at the same 61...

are presented. Did Reeve ever use S30v at 61 RC like the BG-42? How was the performance? Of what form (and magnitude) were the gains in dropping the hardness 2-3 points.
I had an impression that it's what he did. Otherwise how would he come up with a number?

Cliff Stamp · Apr 28, 2003

Lots of heat treating is done without ever exploring the range of possible heat treatments. Again, it is simply a matter of supporting facts. Look for example at Fowler and ask him similar questions about his knives. He will tell you exactly which tests he uses to measure performance, how the steel did on the tests, and how the performance changed (in detail), as he changed his heat treating.

No vague statements about being better or more optimal with no defined terms, but actual concrete descriptions of what is meant by better performance. It is easy to find other examples as well, Glesser will readily detail Spyderco's tests of various steels, and Busse will talk about the R&D done on his blades including live demos of the tests showing aspects of cutting ability, edge retention and durablity.

That is how you make meaningful statements about performance.

-Cliff

OwenM · Apr 30, 2003

Originally posted by Cliff Stamp

Which of course begs the question, how were these abilities actually inferred, and why can't the results of this evaluation process be discussed. This should not be a religious issue where a maker steps in and what he speaks is taken as divine law when no supporting facts are presented.

No vague statements about being better or more optimal with no defined terms, but actual concrete descriptions of what is meant by better performance. It is easy to find other examples as well, Glesser will readily detail Spyderco's tests of various steels, and Busse will talk about the R&D done on his blades including live demos of the tests showing aspects of cutting ability, edge retention and durablity.
That is how you make meaningful statements about performance.

First off - they are selling you a product, and are thus hardly an unbiased source of information.

You'll have to excuse me if I find these statements rather hilarious, since you've been making performance statements about S30V all along, based on zero experience, yet you want documented proof from the people who've actually tested it, and basically call all of these makers liars whose conclusions based on use don't match your assumptions based on speculation.

They are vastly different knives intended for different purposes. Both the BG-42 and S30V blades in question are Sebenzas and I have seen no commentary by Reeve that the S30v blades were designed for different tasks than the BG-42 ones.

No kidding. The point was to differentiate from one steel to the other. Two different steels, with two different sets of properties. They are not equal. CRK's A2 was an example. It could have been any other steel, using a different hardness.

In addition, how many of these makers are doing their own heat treatment. All Bos makers tend to use the same heat treatment (it is one of the selling points), and thus this huge pool of makers is essentially one. Of course if every maker independently had Bos look at different RC schemes this isn't true, but this isn't the case based on what I have read. In fact a lot of makers have written that they simply let Bos decide .

Yep, alot of those makers use the "standard" HT. If you will look back over past threads on S30V, you will see that makers did indeed use Bos for different HTs of S30V when it was brand new, and being tested. Why now, would each individual maker want to do extensive testing of a proven product, rather than using a proven HT?

PWork · Apr 30, 2003

BG-42 vs. S-30-V...My experience.

Both knives are small Sebenzas, a regular (BG-42) and a classic (S-30-v). Both knives are sharpened freehand on medium grit Spyderco ceramic. The S-30-V is MUCH easier to sharpen than the BG-42. Difference in edge retention is nill in day to day use, they seem very close to equal from what I've seen.

I have no experience with either steel from a different maker/heat treater so can not/will not make any claims to contrary comparisons.

S-30-V was developed specifically for cutlery use. That alone makes it a "pioneer" steel. Will something better come down the line? Probably. If and when it does, it too will have it's advocates and detractors. Base your comments on REAL world use.

Chris Reeve (and Chris Reeve Knives) has an impeccable reputation built on experience, experimentation, and customer service. I am more likely to listen to him, and those with REAL world experience, than I am to someone who does not know how to properly use the tool at hand.

Paul

Scott Dog · Apr 30, 2003

Well said Paul!

L.O. Little · Apr 30, 2003

Here's my take on this matter.

I ordered a new (large plain S30V) Sebenza the other day. I could have bought a used BG-42 Sebenza, in perfect condition for less. I bought a S30V. I VOTED with my pocket book. I have faith in Chris Reeve. He knows what he's doing.

You've got to have faith in your knife maker. If not, buy something else from somebody you CAN trust. Then shut up.

Gator97 · Apr 30, 2003

Originally posted by L.O. Little
...I VOTED with my pocket book. I have faith in Chris Reeve. He knows what he's doing.

You've got to have faith in your knife maker. If not, buy something else from somebody you CAN trust. Then shut up.

I don't understand why does it have to be that way, why to "shut up" then or before? You have faith? Good for you, does that automatically exclude your or anybody else's right to ask question or express his opinion?
Knife is a tool, and makers are people, and working on the new steel and finding its best properties is rather trail and error than something predefined, everyone can make a mistake.

L.O. Little · Apr 30, 2003

"I don't understand why does it have to be that way, why to "shut up" then or before?"

IMO, non productive talk is very close to whining. A man of character doesn't whine. A man chooses a direction, then walks that way.

I have nothing against discussion. This discussion/thread, however, is getting VERY old. It appears to be non productive. Will this discussion/thread change anything?

Gator97 · Apr 30, 2003

IMHO it is neither whining nor matter of faith or religion to ask why the maker made particular decision and request testing data if available.
I personally have learned fwe new things regarding S30V based on this thread, may be because I was not following other threads regarding the same subj.

JoHnYKwSt · Apr 30, 2003

When S30V first came out CRK heat treated S30V to 58-59RC, whereas other makers were going as high as 61RC. We questioned CRK because they seemed to be the only ones using the lower RC. Now it seems everyone has the RC about where CRK has kept it all along. CRK was right all along. They have tested S30V extensively, and the fact that they initially heat treated S30V at 58-59RC shows it. CRK does not have to give "raw data" to anyone. It costs them money to conduct tests and no business is obligated to give that data out whether the public expects it or not.

The only thing they have "claimed" is that "their" S30V is easier to sharpen and more stainless when compared to their BG42, yet having about the same edge retention. From the posts I've read this seems to be true. REAL WORLD example would include Pwork and Dennis Wright, off the top of my head.

If someone tests BG42 and S30V head to head and finds results different than the above then they have something to complain about. Also if someone tests S30V with another makers S30V, and finds the other makers S30V holds an edge longer, that may be great and dandy but that was never CRK's goal.

Johnny

Cliff Stamp · May 5, 2003

Owen :

... you've been making performance statements about S30V all along, based on zero experience

I have used a S30V knife, but yes before I had done so, I did comment on the performance I would expect based on my experience with other knives and the materials testing done by crucible. My comments were mainly on the implications of the the lower RC as it directly lowers impaction resistance (that is what RC measures) - this is as much speculation as the statement that a knife which weighs 300 g is lighter than one that weighs 400 g. I don't need to have the knife in hand to make this conclusion. Other comments were made concerning the reduction in strength that is induced by a lower RC, again this is fact not speculation, and the additional fact that the charpy tests done by crucible show no significant gain in impact toughness over 440C and the like. Plus in general there were questions raised as to why the RC was lowered on the S30V considering the success of the BG-42 at the higher hardness.

... you want documented proof from the people who've actually tested it

No requiements were demanded about "proof" simple that terms be defined and some description given as to how conclusions were reached.

... basically call all of these makers liars whose conclusions based on use don't match your assumptions based on speculation.

No I said they are biased, this has nothing to do with lying - and if a maker agrees with me or not is irrelevant, they are all still biased about their own knives. Consider if it came out that a reviewer who wrote a very positive review of a knife was payed a large sum of money directly by that maker / manufacturer to promote said knife - how would that be reacted to by the knife community at large. Knife makers get payed directly in this fashion for all positive promotional claims they make about their knives.

The bias tends to exert itself not towards lies, though there have been cases of this on the forums before (see the SOG 440C / AUS-8 incident for example which some don't see as a lie while many do), few makers actually lie about their knives that I have seen. Mainly it comes through as the promotion of strengths and the ignorance of the weak points. Go to websites and look up how many makers / manufactures list alongside the positive attributes of their knives all the drawbacks. Calculate the ratio and then make a comment about how the commentary is so unbiased .

As a simple example, specific to Reeve. He has noted that the reason that they don't use an oval handle is that it is too difficult to machine. Now is this noted anywhere on the website that an oval handle would be more ergonomic or secure. When people call or email to discuss his knives does he frequently state that they could get better performance in many areas by getting a more oval handle? Does he talk about the reduced edge retention and impaction resistance of the lower RC of the A2? Does he talk about the problems with deep cutting on the hollow grind as opposed to much wider flat grinds? Does he discuss the greater toughness and wear resistance of 3V over A2. Are these points just as strongly stated in ads in magazines or at reps at shows?

CRK's A2 was an example.

Which was completely irrelevant to the point at hand as it was on a different knife built for a different task and thus requiring a completely different set of abilities. The case being discussed was two different steels being used on the same knife with both being built for the same purpose.

Why now, would each individual maker want to do extensive testing ..

To advance the product and of course simply do an independent confirmation. The type of "testing" that you have described, has lead to wide scale problems in many sciences (do some reading on the lipid hypothesis for example) and is the fundamental reason why it is common in robust research to constantly confirm behaviour of others as well as your own group. And of course lots of makers do just this, start with the standard heat treat and spend some time trying to optomize it, just as any other element of the blade. The type of craft you describe is one in which stagnation is common.

L.O. :

You've got to have faith in your knife maker.

There are lots of makers that don't require you to take their word as scripture. As noted in the above, it is trivial to find those that will speak openly about the testing that have done, in detail being specific, and even encourage duplication as they are very interested in R&D and QC issues in general. You want to take a makers statements as faith - fine, however it is not a universal maker demand.

-Cliff

Gator97 · May 5, 2003

I went back to old threads, to sort of follow the developments on S30V. Now, for the record I don't own S30V blade yet, waiting for TTKK from Trace Rinaldi, and AFAIK that's gonna have PB heat treatment. So, I'gonna get pretty good idea later what is is like.

Since several people referred to the past 61 HRC requests...

Originally posted by Barry H

Before you poo-poo S30V and CRK's heat treat you may want to define exactly what you are going to cut.
For one, nobody was poo-pooing S30V, discusson was about optimum hardness for S30C in Sebenza.
Two, considering that Sebenza is a small, hollow grind folder with thin edge most likely it will be used for specific things, not chopping and prying.

I think some of the "experts" around here have been extolling the virtues of a higher heat treat==60 or so.

The following is a quote from the comment made by Crucible representative in that very thread when S30V was new:
"if you are not sure what jobs you will ask of the knife (cutting, prying, picking, chopping, you get the picture) then we recommend HRC 58+/-. If you are sure you only need edge retention (i.e. you know you will only be slicing or carving) then HRC 60+/- is OK. So we think unless you know you are in the latter category, HRC 58 is the best choice... "
Considering that it was Crucible who developed S30V I assume they did some testing as well, in short it was enough to ask a question why 58 in a folder and not 61.
Even if S30V at 58 HRC has the same wear resistance as BG-42 at 61 I would still think S30V in small folder would be better at 61 hrc (compared to S30V at 58hrc).

Unfortunately I don't know about the other makers, it would be very interesting to see what does Phill Wilson do, he has his own heat treatment and always goes for best cutting performance.

Cliff Stamp · May 5, 2003

Gator97 :

... it would be very interesting to see what does Phill Wilson do, he has his own heat treatment and always goes for best cutting performance.

For his small knives, the hardness is usually the maximum that can be obtained, up to 64/65 RC on some of the high alloy CPM's and 62/63 on some of the stainless grades last I heard. He has tested lower hardness levels on many steels and found that the edge rolls too quickly. Wayne Goddard also found the same thing, Wilson credits him as a large influence (as does Fowler).

Phil will also tell you exactly what he has done, getting specific about the testing in detail and the heat treatment. I posted up some comments he made about one and a half years ago about S30V. At the time he was still refining his heat treatment and had not tried oil quenching yet (which further brings up the hardness) . Just drop him an email if you are interested in his perspective on the steel.

-Cliff

OwenM · May 7, 2003

Originally posted by Cliff Stamp
Which was completely irrelevant to the point at hand as it was on a different knife built for a different task and thus requiring a completely different set of abilities. The case being discussed was two different steels being used on the same knife with both being built for the same purpose.

Again, that's the whole point. Not a difference in purpose, but in material properties.
I threw A2 out there simply because there has already been a controversy about CRKs HT of it, and some light shed on the reasoning behind it. They made it fit their idea of what the blade was supposed to do.
All I was saying, however poorly, was that BG-42 and S30V are different materials with a different set of properties, and a different point of diminishing returns when it comes to the relation between individual properties, where you begin to give up more than you gain. The goals for the steel aren't supposed to be the same. I don't think they're trying to recreate BG-42. They're trying to improve on it in general.
From my understanding, S30V's entire reason for being is to achieve a balance that wasn't available with current materials. But as is true with any other steel, to do that, one thing is compromised for another. Edge-holding for toughness. Stength for ductility. And vice versa. Maybe there will never be a consensus on which properties are most desirable, as they will probably vary from one person to the next.
I guess S30V is just the next step toward the "perfect" steel, since it apparently allows less compromise than what was previously available. I'm sure there'll be another steel in the future, to one-up it, that will get just as much talk, and then these discussions can be done all over again

To advance the product and of course simply do an independent confirmation. The type of "testing" that you have described, has lead to wide scale problems in many sciences (do some reading on the lipid hypothesis for example) and is the fundamental reason why it is common in robust research to constantly confirm behaviour of others as well as your own group. And of course lots of makers do just this, start with the standard heat treat and spend some time trying to optomize it, just as any other element of the blade. The type of craft you describe is one in which stagnation is common.

Click to expand...

I agree (well I guess I agree, not knowing, or caring to know, what lipid hypothesis is), but extensive testing of each individual material with various HTs, is beyond the scope of most makers, IMO, whether it be a matter of time, money, equipment, or all of those.
Of course I'd like to see it, and have access to all the results, I just don't think it's practical to expect that, since it's not going to happen.

My current goal is to not use the word "properties" again for the rest of the week

harrydog · Sep 10, 2003

I thought I'd resurrect this thread, since I was doing a little research on S30V, to see how everyone liked it so far.
Regarding the optimal hardness for S30V, I thought I'd add this.
Paul Bos, along with three very prominent knife makers, did extensive testing of S30V. They came to the conclusion that RC 59.5 - 60 is where it should be.
That's not much different than Chris Reeve's 58 - 59.

rdangerer · Sep 10, 2003

Good thread because Sal Glesser has also done a good bit of testing and posted some thoughts:

http://www.bladeforums.com/forums/showthread.php?s=&threadid=270056&highlight=s30v

harrydog · Sep 11, 2003

Thanks for that link.
It looks to me like Sal has corroborated what Paul Bos said. 59-60 is about the optimal range that balances toughness with good edge performance.
Chris Reeve is only down one point from there, and apparently feels that the added toughness and additional ease of sharpening outweigh any adbvantage in edge holding at the slightly higher hardness.
I can understand why so many people disagree with him on that, but it's not a major issue with me... UNLESS people are finding that the edge is too soft and rolls easily at Rc58.
Has that been the case?

rdangerer · Sep 11, 2003

I just re-read that thread. Whew. You picked a good one. Lots of good information and insights, and a certain amount of ground clutter, misinformation, and backwards logic to wade through also. The BF reader is best served if they have a skeptical eye and good BS filters in picking sources to listen to, digest, and incorporate.

Harrydog, I think you should buy a new S30V sebbie, and buy a used BG-42 sebbie, and do some testing side-by-side on the hardness issue and edge roll issue, and tell us what you think.

Great excuse to buy two new folders.

And, I'm not trying to stir the pot with what I'm posting here today. Just some perspective, from one guy, who likes his 4 Sebbies fine.

Rc58-59 to subject to edge roll? You might be able to tell a 58-59 knife apart from a 60-61 knife after some side-by-side testing in looking for edge roll. Maybe in daily use after a while. But if the 58-59 knife is tougher and more abrasion resistant, it may have a broader range of performance vs. varying cutting chores overall.

The original source of confusion and questions came when, after offering BG-42 (and ATS-34 I believe) at Rc60 for years in the Sebbie, Reeve dropped S30V to Rc58-59 target (early incorrect info said Rc57-58, others mutated to Rc56-58, etc). Why the questions? Reeve helped develop S30V with Crucible, and Crucible's stated design goal was to be "A2 tough and 3V in edge retention while being stainless... or as Crucible reps stated in conversations at the 2000 Guild Show, "Stainless 3V" was the goal, a tall one but illustrative, for S30V. I.e., the toughest true "stainless" on the market while having hardenability and carbides to also be good vs. abrasion resistance.

So S30V is tougher than BG-42, and yet Reeve drops hardness target? That is where the questions came from. Lots of things can be inferrred from that, and Reeve didn't really cut through the fog in his responses... he came off as a bit defensive and not completely direct in his commentary. One easy inference is that, well, if S30V is tougher at a given hardness than BG-42, then BG-42 must have been a bit brittle, based on experience and customer response, at Rc60. Chris never allowed this was an inference nor would he address this directly.

What would help somebody like me is a set of toughness vs. hardness curves for both steels, given a good heat treat. Graphs are worth many thousands of words.

Also, know that Rc is not completely linear. The machine uses a conical shaped point they push into the steel under known load and they measure linear travel, but that travel is incurred by a "cone", so the displaced volume of indented/pushed-aside material increases with travel.

An example to illustrate, that does carry a few simplifying assumptions:

Wayne Goddard has stated that, in his testing, a blade at Rc52 will barely hold an edge, as indicated by one or two good cuts on rope. Below that and you have a pry bar with a momentarily sharp edge.

sidebar
anyone who has owned a regular 420 steel bladed knife (not talking about 420HC now) knows how poorly a soft blade holds an edge, and how stubborn the wire edge burr can be to get rid of, calling into limitation the accuracy of the simple statement that "softer is easier to sharpen". Softer is easier to sharpen without a good sharpening stone (e.g. a rock in the boonies), but softer often makes the burr harder to remove, makes it harder to get a good, clean shaving edge without burr. A burr will shave, by the way. Just a weak edge.

Assume for a moment that a practical maximum for today's cutlery steels is in the Rc61 to 62 range (even the tough steels are getting practically at least somewhat brittle past this range, but even here, a restricted (slicing) scope of work for a hard blade, or perhaps special alloys, could be the exceptions to this general rule).

So from "barely a blade" to "practical maximum", you may have ~11 Rockwell C points to work with.

Ignoring non-linearity of the Rockwell test for a moment, this implies that a 2 point change in Rockwell can have a 2/11 percent (18%) change in resistance to edge rolling and impaction (which are for most people not cutting abrasive materials like cardboard and carpet all day, the primary dulling mechanisms). Yeah, this example is laden with simplifying assumptions.

So don't miss the big picture "point": a 1 or 2 point hardness change isn't a 1/60 or 2/60 (1.67% and 3.3%) change in performance. It's a 1/11 or 2/11 (9% to 18%) change in resistance to impaction and edge rolling.

Toughness is typically far more non-linear w/ hardness than is resistance to impaction/edge rolling.

Using the search engine, you can learn that one of Reeve's primary drivers in selecting hardness is an ease of sharpening, which he must believe is of importance in servicing his client base. And that's fine. Also, his A2 at Rc55-57... depending on heat treat and edge profile, A2 can be as tough at 59-60 as it is at 55-57 range, it has a weird double hump in toughness curve (I will say I don't know if the curve I saw was transverse or longitudinal charpy impact toughness... I'd have to dig. And some claim it doesn't translate too well to knives since charpy is run on test blocks, in the interest of full disclosure). So the 55-57 is purposely biased for "ease of field sharpening". Also know that good quality, small, cost effective diamond sharpeners are available for pouch carry in a good field sheath.

You may agree that ease of sharpening should be high on the list of performance attributes to balance, or you may not. Just keep in mind that, in general terms (ignoring grain size for a moment), if it's easier to sharpen it is also easier to roll or otherwise dull. Think about it. Decide for yourself.

And for the record, I own 4 Sebbies. Reeve is a maker who's approach towards tolerances, precision, and QC, I respect greatly. And that convex final sharpened bevel is a gem.

Ok, with all that microanalyzing done: While my Sebbies are (1) ATS-34 and (3) BG-42, I'm sure the S30V's at Rc58-59 work fine. You should buy multiple of them and test the Sebbie in S30V and BG-42, side-by-side, in carefully controlled cutting tests, and tell us what you think.

harrydog · Sep 11, 2003

I've owned 4 Sebbie's, all BG42, but only have one at the moment.
I might just take your advice and buy a new S30V version and do a little testing.