s30v woes

[EDCeeker]

Jerry,

We sometimes disagree about stuff, but your posts in this thread have been right on!

Cliff and his minions of (mostly) total newbs that maybe just got driving learner's permits want to, ahem, split hairs about things that they(mostly) have no understanding of to begin with, and would greatly benefit from knowing when to STFU, but they don't.

Steven, you're making the same mistake I (perhaps mistakenly) attributed to Jerry, only this time there's no mistaking it. You're assuming that because somebody's agreeing with a particular position, particularly if that opinion is shared by Cliff, that person is a clueless noob and has no good cause for their opinion. Or, at least, that's the way you're coming across.

It so-happens that, yes, I don't know diddly about blade steel (comparitively speaking). But I do know how to read. I do know what empirical analysis is. What I have seen and read tells me that some blade steels are "better" (for my purposes) than others. What I have seen and read tells me that some steels are "worse" (for my purposes) than others. I don't need to be a metallurist or knife-maker to know, for example, that 440A generally doesn't hold an edge as well as ATS-34, do I? By the same token: I don't need to be a metallurgist or knife-maker to read of experiences by knife users having problems with S30V chipping. And I don't need to be a metallurgist or knife-maker to figure out that "Hey, I see a lot of discussion about S30V chipping, but no such reports of 154CM doing it."

 

[Jerry Hossom]

It so-happens that, yes, I don't know diddly about blade steel (comparitively speaking). But I do know how to read. I do know what empirical analysis is. What I have seen and read tells me that some blade steels are "better" (for my purposes) than others. What I have seen and read tells me that some steels are "worse" (for my purposes) than others. I don't need to be a metallurist or knife-maker to know, for example, that 440A generally doesn't hold an edge as well as ATS-34, do I? By the same token: I don't need to be a metallurgist or knife-maker to read of experiences by knife users having problems with S30V chipping. And I don't need to be a metallurgist or knife-maker to figure out that "Hey, I see a lot of discussion about S30V chipping, but no such reports of 154CM doing it."

I agree with everything you have said here.

 

[Kohai999]

Steven, you're making the same mistake I (perhaps mistakenly) attributed to Jerry, only this time there's no mistaking it. You're assuming that because somebody's agreeing with a particular position, particularly if that opinion is shared by Cliff, that person is a clueless noob and has no good cause for their opinion. Or, at least, that's the way you're coming across.

MOST of the posters in this and related cases ARE noobs that know jack s**t about steel and knives in general. Do a search using the SEARCH function, and you will see that this is the case.

Regardless of how they FEEL about the subject, the Forums in general would be better served by more reading/listening and less arguing, especially when one does not know what in the heck they are talking about.

I am as guilty of flapping my gums/fingers as anyone, but try to keep the flaunting of my ignorance to some narrowly specific areas.

Best Regards,

STeven Garsson

 

[Jerry Hossom]

Sometimes I wonder why I engage in these discussions. It certainly isn't for fun; I think that's obvious. It also isn't for financial gain; the two factory collaborations I have are for knives made in N690Co. If I were smart I'd probably not argue that S30V is a superior stainless steel, especially since 70% of the knives I make are in steels other than S30V.

 

[SteelDriver]

Why are you taking anything on faith from a salesmen. Ask for direct materials data to support the claims. Ask for facts on the effects of the heat treatment.
...
Now take that proposal and discuss it on SwordForums with the number of independent metallurgists there and see if it holds under critical examination. Bring it to rec.knives and see if it holds up to Johnson's ASM based arguement.
...
Until you have actual actual materials data provided it is just conjecture.

Actual materials data . . . from Crucible? No, that would be biased according to you. I would have to get an independent metallurgical lab to examine the chipped blades. Once I obtain this actual materials data, who will interpret it? Ask some independent metallurgists, you suggested. I am not a metallurgist, Jerry Hossom is not . . . and neither are you. We need real experts in this field. But will you accept what they say? Based on your track record with mete, Satrang, and conan, I doubt it. You will find something to contend, call for more actual materials data, and on and on and on.

For the rest of us, here is Crucible's reply to the issue:

The blade needs to be examined to determine why it is not performing up to expectations. If it is a steel related problem, we at Crucible want to understand the problem so we can fix it. A laboratory investigation needs to be performed and whether this is done by an independent lab or at Crucible, it needs to be done so it can be determined what the real problem is.

I have been in the specialty steel business for 30 years and as a metallurgist I know that the perfect piece of steel has never been made. I also know that when customers are encountering problems with steel there are many variables to consider when trying to zero in on the actual cause of the problem. BUT never rule out the steel itself as the problem and always consider the steel as the number one candidate.

CPMS30V is still a relatively new steel. Thus far its overall performance in the field has been very good. However, that does not mean a bad piece or a bad sheet or a bad lot of CPMS30V hasn't made it into a knife or knives. If this is the case we want to know about it so we can fix it and then prevent it from happening again.

If the problem is not steel related, we want to know what went wrong in processing or heat treatment, or etc., so we can assist our customer in fixing the problem.

Thanks
Scott Devanna

...

Several of the people who have posted mention heat treat as the possible problem related to chipping. You [Cliff Stamp] respond by saying that heat treat should not be the problem leading to chipping since Crucible promoted CPM S30V as easy to heat treat. This is not a valid response. Regardless of the difficulty or ease of heat treatment - if the heat treat is done correctly then we need to look elsewhere for the chipping problem - like the steel, or edge geometry, or grinding & sharpening practice.

Lastly, we are curently investigating CPM S30V blades that have chipped. When we determine the cause of this chipping we will make the information available.

I would like to hear what Crucible has to say; perhaps we could contact them and ask for this information. Cliff, keep holding out for that actual materials data, and let us know when your independent metallurgists have finished reviewing it so we can compare those results to Crucible's claims.

 

[Cliff Stamp]

Actual materials data . . . from Crucible?

From any published source which isn't in contention with known material behavior. If it is in contention with known materials behavior it has to be held to a very fairly critical examination obviously. What you are speaking about however are not simply issues just on specific steels but general behavior of steels.

No, that would be biased according to you.

Obviously, you don't think so? Do you think McDonalds is an unbiased source of information on how healthy it is to consume significant amounts of their food. That is why you gather a bunch of data from different sources, ask independent experts (more than one) and get educated yourself. If you check a tool steel reference book such as Robert's and Cary they don't get all the information from one manufacturer, that would just be foolish. You get all available information from everyone and then you examine for trends, induce the underlying behavior, etc. .

I would have to get an independent metallurgical lab to examine the chipped blades. Once I obtain this actual materials data, who will interpret it?

The people you would pay to get it done obviously. It is also likely if you had more than one lab do the tests they would not all get the same results. There is always disagreement in the scientific community which is why your constant jibes about acceptance is completely absurd.

We need real experts in this field. But will you accept what they say?

If it makes sense, science isn't about faith.

Based on your track record with mete, Satrang, and conan, I doubt it.

You can add Roman Landes, Fredrik Haakonsen, Verhoeven and Krauss to that list as well. I have had exchanges with all of them and none of them were religious in nature nor do you expect it in an scientific exchange. I also know easily a couple of dozen of engineers of various fields, many of my closest friends are engineers, and I don't accept anything they say blindly either, and of course none of them do with each other or with me.

If you were actually part of the scientific community you would know that it is expected that anything you say has to be supported and self-consistent and even a full professor can't dismiss the question of simple undergrad. It isn't about acceptance, it is about making an arguement which is based on facts and logic and is consistent. You should be able to explain it to a lay person and have them see the facts and logic, if you can't then you don't understand it yourself.

Read any of Feynmans books and realize what it means to be a scientist and how absurd it is to even postulate than anything be accepted on faith. It doesn't matter who says it. You ask an expert because you hope they can give you the relevant facts and logic not because you are looking for a messiah to tell you what to believe. That isn't science, that is religion and that viewpoint has no part in any discussion of such matters.

A salesmen doesn't want anything they say critized a scientist does and will in fact constantly seek it out. It isn't hard to tell them apart.

-Cliff

 

[OldPhysics]

Bravo, Mr. Stamp.

I've been a trained, practicing scientist for over 30 years, and this is the best explication of the need (no, requirement) for rational inquiry and objective debate I've yet heard.

Truly, it is about well-supported facts and carefully constructed arguments and not about attitude, opinion, or even faith.

It's hard to separate the ego from the argument, though, isn't it?

 

[Cobalt]

P/M's have a significant grain due to rolling this is why they impact test different in the longitudinal/transverse directions.

Actually, PM's have similar impact toughness in transverse and longitudinal directions. It is the rolled steels that have different impact toughness in either direction.

The reason that you have to extensively roll cast ingot steels, especially the high alloy ones is to break up the dendretic carbides and try to make the composition more uniform. It would be expected that P/M's would thus require less rolling because they inhernetly have a much better alloy distribution and far less segregation. Compare the micrographs of ATS-34 (ingot) vs RWL34 (P/M) I posted that Landes took for example. Note that P/M's are essentially just a bunch of very small ingots that are forged welded by compression. They are also then rolled.

Forge welded? such a nice term for sintering. Let's get real here. Compressing a powder is not better than melting ore. Even though the individual particles are homogenous in microconstituents, I have a hard time believing that the molecular bond is as strong. So n effect you have a more homogenous steel, better on paper, but you have a process that IMO does not bond at the molecular level as well, and thus the results we are currently seeing. But what do I know, I am not a knifemaker, just an M.E. with materials background and no recent experience(in the last 8-9 years) in that field. I hope I am wrong about this and I hope that the current theory is right, because I like to see new steels make it, but the chipping I see with all these steels only verifies what I have thought all along about this process.

Now, if you forged these steels mechanically, then I can see big improvements over other steels.

In general, for similar alloy composition, P/M are tougher than ingot steels, there is a wealth of published data on this all due mainly to the lower segregation and more uniform composition. P/M's are in general a good thing and the main reason they are not used more is just cost, it is cheaper to make ingot steels. You have to be aware though that alloy composition has to be considered.
-Cliff

testing does not prove this theory does it...This thread and many others on this subject are proof of that. Why people are going back to other steels like ATS34, BG42, etc. would show this to not be the case. You have said it yourself, on paper thse steels look great, but in actual tests, you yourself have proven them not to be so great. Or have I misread your testing.

You yourself have destroyed a knife made of these steels and yet knives made of supposedly inferior process survived (Custom 52100 and INFI), why?

 

[Cliff Stamp]

It's hard to separate the ego from the argument, though, isn't it?

That is usually the central problem. It isn't difficult to spot when this is the case but actually eliminating the contention is difficult because conflict resolution is dependent on bilateral acceptance of independent point of views. If someone is trying to sell you something and you contend it, there is zero possibility of a resolution because they have no consideration that their sales pitch is wrong.

-Cliff

 

[searcher]

...

Yes as these are commonly all tempered very hot as I noted, you don't get the same phase transformations with low tempers. If for example you took M2 and tempered it low, even a bunch of times, you would not transform the austensite by inducing martensite to form. You can't even minimize retained austenite with cold treatment which Landes noted which surprised me. The really high alloy steels require the conditioning of the high tempers because the austenite stabilizes extremely rapidly.

... What sources, actual materials references or just makers selling the steel? There is a wealth of materials data on the effects of air vs oil on air hardening steels, this isn't an issues specific to a couple of CPM steels. They are of course used in industry with just air hardening as that is how they were designed. You can also just ask the manufacturers directly (look at the published data) you can expect a small increase in the hardness, 1-2 points, and small effects on corrosion resistance/toughness, with the latter being also effected by the lower hardness. Landes has studied this in detail as well which is why he does water quenching after tempering so you can discuss it with him and he will be very specific about what it does. However if you don't water quench after tempering it doesn't mean the steel is ruined, again, this is a small refinement.

-Cliff

Here is a link to S30V data sheet. Tempering temperature is 400-600 degrees F. This is a low tempering temperature. Double temper is REQUIRED with sub-zero (dry ice temperature) quench recommended after oil quenching. Note the comment about greater resistance to chipping and greater transverse toughness than 440C and 154CM.

http://www.crucibleservice.com/datash/dsS30Vv5.pdf?CFID=855543&CFTOKEN=53335224

 

[knarfeng]

MOST of the posters in this and related cases ARE noobs that know jack s**t about steel and knives in general. Do a search using the SEARCH function, and you will see that this is the case.

Regardless of how they FEEL about the subject, the Forums in general would be better served by more reading/listening and less arguing, especially when one does not know what in the heck they are talking about.

I am as guilty of flapping my gums/fingers as anyone, but try to keep the flaunting of my ignorance to some narrowly specific areas.

Best Regards,

STeven Garsson

Steven,
One should not assume that because some one is new on this site that he is new to knives and does not know jack about steel. The world of steel and of knives is far more diverse than this one bulletin board. It is also more diverse than the high art of making knives.

F. M. Rawolle
materials engineer, knife user for 46 years, new to this site.

 

[sodak]

Steven,
One should not assume that because some one is new on this site that he is new to knives and does not know jack about steel. The world of steel and of knives is far more diverse than this one bulletin board. It is also more diverse than the high art of making knives.

F. M. Rawolle
materials engineer, knife user for 46 years, new to this site.

Thank you.

 

[HoB]

Actually, PM's have similar impact toughness in transverse and longitudinal directions. It is the rolled steels that have different impact toughness in either direction.

Well, depends on what you call "similar". The difference for S30V is a factor of three....because the steel IS rolled after HIPing.

Forge welded? such a nice term for sintering. Let's get real here. Compressing a powder is not better than melting ore.

Well, they are HIPed. While I agree that the difference between sintering and HIPing is marginal if you want to understand the underlying physics, the outcome is quite different. HIPing produces near 100% density. As to the melting: the constituents are melted either way, only in HIPing you are utilizing the surface free energy to achieve a "melting" below the actual melting point. The particles are fused not just compressed together. The big advantage is, that this way material transport is limited and aggregation of the constituents is eliminated.

 

[Cliff Stamp]

Actually, PM's have similar impact toughness in transverse and longitudinal directions. It is the rolled steels that have different impact toughness in either direction.

Ingot steels have a greater difference yes and this would be expected due to the higher segregation. With P/M's the increase is generally uniform, you are not trading a more equal impact toughness with a lower total magnitude, you just don't see the magnitude of the difference between cross/along the grain as you do in ingot steels.

Compressing a powder is not better than melting ore. Even though the individual particles are homogenous in microconstituents, I have a hard time believing that the molecular bond is as strong. So n effect you have a more homogenous steel, better on paper, but you have a process that IMO does not bond at the molecular level as well, and thus the results we are currently seeing.

As HoB noted, it isn't just a compression like packing sand, but under significant pressure so the steel will become uniformly bonded. It isn't a molecular bond though but a metallic one. There is some issue about voids and P/M's are not 100% solid so there is a valid question here about the exact level which the various manufacturers have as their tolerance as they all use different methods.

Now, if you forged these steels mechanically, then I can see big improvements over other steels.

They are rolled. They can also be hammer forged, many makers have done this, but it would be hard to argue that didn't do anything but make it worse because that tends to induce uneven grain growth.

Or have I misread your testing.

No, I have said that about 3V, it has not performed as I would have assumed from the promotional material. However there are many things which can effect this and until I get a known custom from a maker like Wilson who will be specific about what he does and frank about the results I am still open to the material but would obviously not promote it as being superior. Wilson's S30V blade for example is a nice example of a moderate/high wear resistant stainless steel so works well for cutting abrasive material with the known drawbacks of lower toughness, grinability, higher cost, lower edge stability, etc., of steels like 13C26.

One of the most frank comments about 3V I have seen was made by Landes who is a metallurgist (who specialized in knife steels) and knifemaker who has considerable experience with P/M's :

Well in terms of carbide size there 3V is definately good. So edge stability is expected to be close to simple tool steels like O1, O2, file, ballbearings, etc.

The difference is, that the correct HT is way more complex and needs a high efford and costs for purchasing it will also be higher. If one wants to forge 3V there are way more rules to obey than with the "easy steels"

So in terms of edgeholding for fine edges with acute angles for very sharp knives, wich will be the best application for this type of steel, you dont have a real technological advantage by using it. Instead you have more costs and effort working it.

Of course there is the "Advantage of Hype" it is expensive and PM

The last sentance is of course what I have noted in the above, makers using a steel simply because it can be promoted as being unique and thus desireable.

... made of supposedly inferior process survived...

This is again another valid point which is ignored in the massive hype engine about P/M's. When the alloys are of similar composition a P/M is tougher and more uniform in compostion with less segregation. Howeveryou also have to consider the influenced of the alloy. Stainless steels like 12C27 are far tougher with higher edge stability than steels like CPM154 and are far cheaper and easier to heat treat and grind.

It is no different for example that noting that simply because a knife is made out of a tougher steel it doesn't mean it is tougher than another knife which has a different shape because geometry is very important as well. So you have to consider both factors just like manufacturing process and alloy content are critical in steels, not just one or the other.

I think it would be interesting to talk to the makers using P/M from Erasteel and similar to see if they have seen chipping issues as they have similar steels. Fredrik Haakonsen has had very impressive results with them (metallurgist/SwordForums).

-Cliff

 

[flatgrinder]

CPM S30V is a good steel -as long as it has been heat treated properly.

 

[SteelDriver]

Obviously, you don't think so? Do you think McDonalds is an unbiased source of information on how healthy it is to consume significant amounts of their food. That is why you gather a bunch of data from different sources, ask independent experts (more than one) and get educated yourself.

Even McDonalds has nutrition information available for all their food. There's a difference between what they advertise and these FDA-mandated reports. I'm not saying you should not consult independent experts and I'm not saying you should believe Crucible's ads, I'm saying that you also have to take Crucible's data into consideration. You would rather ignore it altogether as biased.

There is always disagreement in the scientific community which is why your constant jibes about acceptance is completely absurd.

I have not advocated accepting Crucible's view without question; in fact we don't know their findings on the problem yet. The theories of poor HT and grinding practices did not originate from Crucible, though they admitted it as the probable cause. I'm not aware of any independent labs doing testing on these chipped blades. As I said before, if you do, please let us know so we can compare it to Crucible's results. However, I'm not optimistic that we will in fact have these independent test data. I think these two theories are probable causes, and you obviously do not. Neither of us has provided actual material data to support our views, thus you are demonstrating as much "faith" as me by your own definition.

You ask an expert because you hope they can give you the relevant facts and logic not because you are looking for a messiah to tell you what to believe. That isn't science, that is religion and that viewpoint has no part in any discussion of such matters.

A very good effort to uplift your position as "science" and discredit mine as "religion." If your reasoning about bias and faith holds, nobody should believe anything you say in your own knife reviews for example. You don't have to be the manufacturer of a product to be biased. I haven't seen independent test data to verify your scientific knife testing, so why should I have faith in it?

 

[EDCeeker]

I think these two theories are probable causes, and you obviously do not. Neither of us has provided actual material data to support our views, thus you are demonstrating as much "faith" as me by your own definition.

That's not the impression I get. The impression I get is that Cliff isn't willing to accept any explanation w/o proof. All there is now is conjecture, no? IOW: On what basis do you lend credence to the two theories (they're really conjectures)?

You don't have to be the manufacturer of a product to be biased. I haven't seen independent test data to verify your scientific knife testing, so why should I have faith in it?

Because it would appear everything he does is right out there in the open (ostensibly)? Because, unless we're to believe he's on the take from a lot of different manufacturers and makers, there's no profit in his falsifying his tests?

 

[Jerry Hossom]

SteelDriver, thanks for the perspective.

Allow me a couple anecdotal observations and maybe a fact or two that I believe can be accepted at face value.

I question whether heat treating is responsible for chipping. Brittleness is not the normal failure mode in heat treating S30V. The most common problem in heat treating the steel is a slow quench, failure to get below the martensitic start temperature in a very short time, probably less than ~minute, resulting in a softer steel (arguably less likely to chip). This was the reason many knifemakers went to using quench plates for achieving a fast quench. It's also one of the reasons some knifemakers were unhappy with S30V initially, before this was known. (And BTW, this problem first manifested itself with CPM-3V which a few knifemaker still believe is an inferior steel.) Individual knifemakers seldom have atmospherically controlled ovens and must wrap their blades in stainless foil to prevent decarburization. That foil envelope retards cooling in still or even forced air, hence the quench plates for quickly drawing off heat. Factories use either atmospherically controlled ovens with a cold nitrogen purge or they use salt baths for both hardening and the initial quench, both achieving a fast quench. Regardless of the way it's done, in my judgement it's unlikely this is a common source of error today, if for no other reason than that it's been discussed repeatedly among knifemakers at all levels, forever. I do believe this was a common problem before the quench issue became widely known, but again the result of this error is a softer steel. Could there be concurrent failure modes, both soft and brittle? Sure, but I would expect rolled edges to be reported along with brittle failure - one the result of running an edge along a hard object, the other as a result of an impact. To my knowledge this hasn't been reported.

It's possible that an extended soak time at the hardening temperature could induce brittleness, but in 20+ years of knifemaking I've never encountered that happening, certainly not repeatedly at several locations. A newcomer to knives MIGHT make that mistake since steel companies give heat treating schedules that are more appropriate for thicker sections than we're dealing with, but any experienced knifemaker know that and is more likely to err on the short soak side. Knife factories are very unlikely to make either of this mistakes; all of their experience and history has taught them the soak time needed at hardening temperature for knife blade sections, and use very accurate thermocouples to ensure they know exactly what that temperature is and when they get there.

Despite the fact that Crucible has not been very helpful in supplying effective technical guidance to its customers using it's steels, knifemakers have become pretty adept at finding their own course through this minefield. In fact I know Crucible consulted with Paul Bos to arrive at the 600F tempering temperature, rather the 400F temper that was first published. My first S30V blades were hardened at 950F and in some brief of testing I found the steel was slightly tougher at that temperature than at 600F. 600F was a compromise to provide toughness while retaining a high level of corrosion resistance.

I believe the chipping problem is edge finish, possibly associated with some of the machining difficulties with S30V that set it apart from all other steels I've dealt with. When S30V first came into the market and I had worked with some of the earliest samples, Crucible was sending some knifemakers to me to discuss how to work with the steel and to answer any questions I might be able to. To the question regarding working with the steel I suggested either strong, profane language or prayer depending on their preferences; I had tried both.

On the problem side I heard two problems repeated by some of the more experienced knifemakers. "This steel isn't holding an edge" AND "I'm seeing some chipping." What was perplexing about this for most was that these were precisely the two issues that S30V was designed to address - a tough, high vanadium stainless.

After a number of these discussions, in which I described exactly what I was doing with the streel, and my reasons for why, the same thing appeared tp be the dominant variable in both situations. Edge finish. Unless the S30V edge is finished to ~600 grit or beyond (that varies because of some proprietary sharpening methods used by a few makers), S30V will not hold an edge and will be prone to chipping. Given a highly finished edge the steel hold that edge for a very long time and is not prone to chipping.

Any knifemaker who has worked with S30V knows that it really doesn't like to take a high finish, and especially not a polished finish. It also tends to hide scratches as you move from one grit to another. You won't see any scratches remaining at 120 grit, but at 400 grit you see scratches that appear to be from the 60 grit belt. If you try to jump from 120 grit to 600 grit, it will punish you. Also, unless you are prepared to expend 4-5 belts per blade, you have to carefully select the type of belts you use and use somewhat less pressure to allow the abrasive to cut more cleanly. The first S30V blade I finished required two full days following heat treat, and it ate about 6-7 of my 3M Trizact belts (at about $5 ea.).

Now why am I saying this? You can't just lay an S30V edge on a 220 grit belt, raise a wire along that edge, strop it off, and think you have an edge that will last. Those toothy edges that some prefer simply don't work with S30V (I don't think they work with any steel, but I won't go there.). I've not examined those teeth microscopically, but I know they break off quickly and when they do the blade is dull. That is true of many steels with that edge, but for some reason it's worse with S30V. With a 15 or 6 micron edge, the steel is great at edge holding. This was the first thing that became apparent when these problems appeared. Next the chipping. Once again a fine edge finish eliminated the problem. Here though the problem might be a bit more demanding. Crack formation in steel increases as the size of a notch decreases. With a difficult to finish steel, fine notches are likely. You can actually have a polished (appearing) edge that under some magnification will have scattered deep scratches from one of the coarser grits used in shaping the edge. That often happens when you skip grits in finishing - jumping from 120 to 400 or even more noticeable jumping from 320 grit to 15 or 6 microns. Those scratched are notches, the notches are stress risers, stress risers cause hardened steel to crack, cracks lead to chips.

Yes, the problem is S30V because it is difficult to finish, but with a proper edge finish S30V is a magnificent steel.

Perhaps that explains some of the conflicting reports in the steel's quality.

 

[Keith Montgomery]

I don't believe there is anybody more knowledgeable about the characteristics of S-30V the Jerry Hossom. Jerry, thank you very much for taking the time to provide us with this information.

 

[EDCeeker]

Little do I know of steel, and even less of cutlery steel or knifemaking, but your analysis, Jerry, certainly seems to make sense. And it does seem to explain the paradox'. Thanks for taking the time to write that up!

I presume the same edge-finishing issues that will plague the knifemaker are likely to affect the user? This might explain why (sometimes?) a good re-sharpening of a S30V edge prone to chipping makes the problem go away, as has been reported.

Btw: I may be setting myself up with a Basic Membership, at which point I'd be allowed a signature. It seems to me this quote of yours would do nicely:

"To the question regarding working with the steel I suggested either
strong, profane language or prayer depending on their preferences;
I had tried both." -- Jerry Hossom, KnifeMaker, on S30V

May I?