"HRC as advertised." Who is accurately listing HRC?

[bluntcut]

They have similar corrosion resistance and similar carbide volume, except s90v primary carbide is vanadium (also smaller carbide than m390) so s90v is more wear resistance than m390/204p/20cv at same edge geometry and sharpening. my actual usage experience (casual observation rather than quantitative) seem agreed with my wear resistance assessment.

...

Thanks again ! Given Larrin's numbers on corrosion resistance (viewtopic.php?f=2&t=82616), sounds like with your heat-treat, same grit and geomtery, s90v and m390/204p/20cv turn out to be very similar steels for the user, would you agree ?

Roland.

[ferider]

They have similar corrosion resistance and similar carbide volume, except s90v primary carbide is vanadium (also smaller carbide than m390) so s90v is more wear resistance than m390/204p/20cv at same edge geometry and sharpening. my actual usage experience (casual observation rather than quantitative) seem agreed with my wear resistance assessment.

[Ankerson]

Reasonable would depend on who is doing the heat treating and what the Company says that it wants and if it's actually obtainable in a production setting. And if the actual HT is worth a crap when the Company tests it.

That will vary greatly depending on the variables.

Optimal would depend on the actual knife in question and that will also vary.

So the answer is that it depends.

Thanks. Still, people are very vocal about optimal M390 HRC being - say - around 62. And Spyderco obviously can achieve it. So for a company that you trust in doing good HT (for production knives), and achieving good HRC to optimize a knife's performance, which standard deviation is acceptable to you ? How large does it have to go to become "crap" ? Must be some number, as even Spyderco can not crank out thousands of knives all at 62.0 HRC flat.

Speaking as an engineer, I would think that the HRC stddev is the true metric of the maker's manufacturing quality. So what should it be for a good maker ?

There is a massive difference in commercial HTing and a custom maker doing one or 2 blades at a time.

IT IS MASSIVE

NOBODY CAN hit HRC numbers exact 100% of the time, too many variables involved for that to happen.

Anyone that tells you different..... Well...

Not too many aerospace level furnaces around and NONE are being used for heat treating knife blades.

[Banter 247]

I’m pleasantly surprised with the way the conversation has evolved on this forum. Much more consistently level headed than I expected. Thank you to everyone for the ways you’ve each participated.

[ferider]

There is a massive difference in commercial HTing and a custom maker doing one or 2 blades at a time.

IT IS MASSIVE

NOBODY CAN hit HRC numbers exact 100% of the time, too many variables involved for that to happen.

Anyone that tells you different..... Well...

Not too many aerospace level furnaces around and NONE are being used for heat treating knife blades.

Well, similar to what bluntcut explained, a mass producer could test knives as part of the final QA and scrap blades that do not pass the final HRC yield criteria. Would of course raise the costs, and bluntcut was kind enough to add a cost analysis. Note that this is very common practice in other industry segments (for example semiconductors, which I know more about than knives :) )

For cost savings, like you, I assume they don't and produce an HRC range instead.

Two reasons why I asked:

(1) the stddev is a good indicator of the manufacturers quality.
(2) the business aspect (in answer to the OP):

I have two custom knives from a Russian maker (AB) that have HRC etched on the blade. For mass production knives, some manufacturers provide the above range (e.g., Hinderer says 59-60 HRC for 20CV). Others don't. From a business perspective, given an HRC range, a mass producer would never imprint the actual HRC on the blade, because the knives on the lower end of the range would not sell.

Roland.

[Ankerson]

There is a massive difference in commercial HTing and a custom maker doing one or 2 blades at a time.

IT IS MASSIVE

NOBODY CAN hit HRC numbers exact 100% of the time, too many variables involved for that to happen.

Anyone that tells you different..... Well...

Not too many aerospace level furnaces around and NONE are being used for heat treating knife blades.

Well, similar to what bluntcut explained, a mass producer could test knives as part of the final QA and scrap blades that do not pass the final HRC yield criteria. Would of course raise the costs, and bluntcut was kind enough to add a cost analysis. Note that this is very common practice in other industry segments (for example semiconductors, which I know more about than knives :) )

For cost savings, like you, I assume they don't and produce an HRC range instead.

Two reasons why I asked:

(1) the stddev is a good indicator of the manufacturers quality.
(2) the business aspect (in answer to the OP):

I have two custom knives from a Russian maker (AB) that have HRC etched on the blade. For mass production knives, some manufacturers provide the above range (e.g., Hinderer says 59-60 HRC for 20CV). Others don't. From a business perspective, given an HRC range, a mass producer would never imprint the actual HRC on the blade, because the knives on the lower end of the range would not sell.

Roland.

It would likely triple the cost because they would have to make up for the losses and still make their margin.

So it would be cost prohibitive to say the least for production knives.

People have to be realistic and if the maker states a range then take it for what it's worth.

Maybe just start using their knives and enjoying them rather than worrying about things that really don't matter enough in everyday use for MOST people to see.

Most people will never see the difference in performance unless the actual testing removes the variables and they have other knives tested the exact same way with actual measurable data to compare it to.

Too many variables in real world use to actually see a real difference that wouldn't be something else like sharpening and or varied use that would be way to varied for any sort of real comparison.

Most of the time people are comparing apples and oranges and wonder why there is a difference.

My recommendations:

Get the knife that you like.

Learn how to sharpen it well.

Keep it sharp.

Enjoy it.

[Banter 247]

There is a massive difference in commercial HTing and a custom maker doing one or 2 blades at a time.

IT IS MASSIVE

NOBODY CAN hit HRC numbers exact 100% of the time, too many variables involved for that to happen.

Anyone that tells you different..... Well...

Not too many aerospace level furnaces around and NONE are being used for heat treating knife blades.

Well, similar to what bluntcut explained, a mass producer could test knives as part of the final QA and scrap blades that do not pass the final HRC yield criteria. Would of course raise the costs, and bluntcut was kind enough to add a cost analysis. Note that this is very common practice in other industry segments (for example semiconductors, which I know more about than knives :) )

For cost savings, like you, I assume they don't and produce an HRC range instead.

Two reasons why I asked:

(1) the stddev is a good indicator of the manufacturers quality.
(2) the business aspect (in answer to the OP):

I have two custom knives from a Russian maker (AB) that have HRC etched on the blade. For mass production knives, some manufacturers provide the above range (e.g., Hinderer says 59-60 HRC for 20CV). Others don't. From a business perspective, given an HRC range, a mass producer would never imprint the actual HRC on the blade, because the knives on the lower end of the range would not sell.

Roland.

It would likely triple the cost because they would have to make up for the losses and still make their margin.

So it would be cost prohibitive to say the least for production knives.

People have to be realistic and if the maker states a range then take it for what it's worth.

Maybe just start using their knives and enjoying them rather than worrying about things that really don't matter enough in everyday use for MOST people to see.

Most people will never see the difference in performance unless the actual testing removes the variables and they have other knives tested the exact same way with actual measurable data to compare it to.

Too many variables in real world use to actually see a real difference that wouldn't be something else like sharpening and or varied use that would be way to varied for any sort of real comparison.

Most of the time people are comparing apples and oranges and wonder why there is a difference.

My recommendations:

Get the knife that you like.

Learn how to sharpen it well.

Keep it sharp.

Enjoy it.

I’m all for enjoyment and perspective, but if a maker of any product puts a product out to entice me with promise that the thing can be better, I expect them to deliver on the promise.

As for variables in the real world, the same is true for fuel economy, estimated sheet yield for printer cartridges, laptop charge duration, and many other product metrics. The intent is never perfect expectation, instead serving as what amounts to a relative spitball reference. I know that you’re plenty aware of this. None among us looks at an edge retention test and walks away with a vision of cutting exactly X amount of cardboard or rope.

Part of my ownership experience is feeling good about getting what I paid for, and I have yet to meet anybody who bought M390 with the expectation that it would behave like S30V, or worse, that it might dull in 35 feet of cardboard cutting because the process was blown.

I’m not trying to be hostile here, just engaging in respectful conversation. I know who you are, and am thankful for your presence in the community. I hope that comes through clearly.

[Ankerson]

There is a massive difference in commercial HTing and a custom maker doing one or 2 blades at a time.

IT IS MASSIVE

NOBODY CAN hit HRC numbers exact 100% of the time, too many variables involved for that to happen.

Anyone that tells you different..... Well...

Not too many aerospace level furnaces around and NONE are being used for heat treating knife blades.

Well, similar to what bluntcut explained, a mass producer could test knives as part of the final QA and scrap blades that do not pass the final HRC yield criteria. Would of course raise the costs, and bluntcut was kind enough to add a cost analysis. Note that this is very common practice in other industry segments (for example semiconductors, which I know more about than knives :) )

For cost savings, like you, I assume they don't and produce an HRC range instead.

Two reasons why I asked:

(1) the stddev is a good indicator of the manufacturers quality.
(2) the business aspect (in answer to the OP):

I have two custom knives from a Russian maker (AB) that have HRC etched on the blade. For mass production knives, some manufacturers provide the above range (e.g., Hinderer says 59-60 HRC for 20CV). Others don't. From a business perspective, given an HRC range, a mass producer would never imprint the actual HRC on the blade, because the knives on the lower end of the range would not sell.

Roland.

It would likely triple the cost because they would have to make up for the losses and still make their margin.

So it would be cost prohibitive to say the least for production knives.

People have to be realistic and if the maker states a range then take it for what it's worth.

Maybe just start using their knives and enjoying them rather than worrying about things that really don't matter enough in everyday use for MOST people to see.

Most people will never see the difference in performance unless the actual testing removes the variables and they have other knives tested the exact same way with actual measurable data to compare it to.

Too many variables in real world use to actually see a real difference that wouldn't be something else like sharpening and or varied use that would be way to varied for any sort of real comparison.

Most of the time people are comparing apples and oranges and wonder why there is a difference.

My recommendations:

Get the knife that you like.

Learn how to sharpen it well.

Keep it sharp.

Enjoy it.

I’m all for enjoyment and perspective, but if a maker of any product puts a product out to entice me with promise that the thing can be better, I expect them to deliver on the promise.

As for variables in the real world, the same is true for fuel economy, estimated sheet yield for printer cartridges, laptop charge duration, and many other product metrics. The intent is never perfect expectation, instead serving as what amounts to a relative spitball reference. I know that you’re plenty aware of this. None among us looks at an edge retention test and walks away with a vision of cutting exactly X amount of cardboard or rope.

Part of my ownership experience is feeling good about getting what I paid for, and I have yet to meet anybody who bought M390 with the expectation that it would behave like S30V, or worse, that it might dull in 35 feet of cardboard cutting because the process was blown.

I’m not trying to be hostile here, just engaging in respectful conversation. I know who you are, and am thankful for your presence in the community. I hope that comes through clearly.

Can you tell the difference in M390 and S30V in real world use?

They are actually pretty close performance wise depending.

If a blade dulls in 35 ft of cardboard assuming that it was sharpened correctly then it's time to contact the maker.

[Pelagic]

Well, similar to what bluntcut explained, a mass producer could test knives as part of the final QA and scrap blades that do not pass the final HRC yield criteria. Would of course raise the costs, and bluntcut was kind enough to add a cost analysis. Note that this is very common practice in other industry segments (for example semiconductors, which I know more about than knives :) )

For cost savings, like you, I assume they don't and produce an HRC range instead.

Two reasons why I asked:

(1) the stddev is a good indicator of the manufacturers quality.
(2) the business aspect (in answer to the OP):

I have two custom knives from a Russian maker (AB) that have HRC etched on the blade. For mass production knives, some manufacturers provide the above range (e.g., Hinderer says 59-60 HRC for 20CV). Others don't. From a business perspective, given an HRC range, a mass producer would never imprint the actual HRC on the blade, because the knives on the lower end of the range would not sell.

Roland.

It would likely triple the cost because they would have to make up for the losses and still make their margin.

So it would be cost prohibitive to say the least for production knives.

People have to be realistic and if the maker states a range then take it for what it's worth.

Maybe just start using their knives and enjoying them rather than worrying about things that really don't matter enough in everyday use for MOST people to see.

Most people will never see the difference in performance unless the actual testing removes the variables and they have other knives tested the exact same way with actual measurable data to compare it to.

Too many variables in real world use to actually see a real difference that wouldn't be something else like sharpening and or varied use that would be way to varied for any sort of real comparison.

Most of the time people are comparing apples and oranges and wonder why there is a difference.

My recommendations:

Get the knife that you like.

Learn how to sharpen it well.

Keep it sharp.

Enjoy it.

I’m all for enjoyment and perspective, but if a maker of any product puts a product out to entice me with promise that the thing can be better, I expect them to deliver on the promise.

As for variables in the real world, the same is true for fuel economy, estimated sheet yield for printer cartridges, laptop charge duration, and many other product metrics. The intent is never perfect expectation, instead serving as what amounts to a relative spitball reference. I know that you’re plenty aware of this. None among us looks at an edge retention test and walks away with a vision of cutting exactly X amount of cardboard or rope.

Part of my ownership experience is feeling good about getting what I paid for, and I have yet to meet anybody who bought M390 with the expectation that it would behave like S30V, or worse, that it might dull in 35 feet of cardboard cutting because the process was blown.

I’m not trying to be hostile here, just engaging in respectful conversation. I know who you are, and am thankful for your presence in the community. I hope that comes through clearly.

Can you tell the difference in M390 and S30V in real world use?

They are actually pretty close performance wise depending.

I think that's a portion of the problem.

[Ankerson]

It would likely triple the cost because they would have to make up for the losses and still make their margin.

So it would be cost prohibitive to say the least for production knives.

People have to be realistic and if the maker states a range then take it for what it's worth.

Maybe just start using their knives and enjoying them rather than worrying about things that really don't matter enough in everyday use for MOST people to see.

Most people will never see the difference in performance unless the actual testing removes the variables and they have other knives tested the exact same way with actual measurable data to compare it to.

Too many variables in real world use to actually see a real difference that wouldn't be something else like sharpening and or varied use that would be way to varied for any sort of real comparison.

Most of the time people are comparing apples and oranges and wonder why there is a difference.

My recommendations:

Get the knife that you like.

Learn how to sharpen it well.

Keep it sharp.

Enjoy it.

I’m all for enjoyment and perspective, but if a maker of any product puts a product out to entice me with promise that the thing can be better, I expect them to deliver on the promise.

As for variables in the real world, the same is true for fuel economy, estimated sheet yield for printer cartridges, laptop charge duration, and many other product metrics. The intent is never perfect expectation, instead serving as what amounts to a relative spitball reference. I know that you’re plenty aware of this. None among us looks at an edge retention test and walks away with a vision of cutting exactly X amount of cardboard or rope.

Part of my ownership experience is feeling good about getting what I paid for, and I have yet to meet anybody who bought M390 with the expectation that it would behave like S30V, or worse, that it might dull in 35 feet of cardboard cutting because the process was blown.

I’m not trying to be hostile here, just engaging in respectful conversation. I know who you are, and am thankful for your presence in the community. I hope that comes through clearly.

Can you tell the difference in M390 and S30V in real world use?

They are actually pretty close performance wise depending.

I think that's a portion of the problem.

Yeah it's one of the mid range steels, S35VN, S30V, CPM 154, ELMAX and M390, they all are really close enough performance wise depending that it can be hard to tell the difference in them in real world use.

[Pelagic]

I’m all for enjoyment and perspective, but if a maker of any product puts a product out to entice me with promise that the thing can be better, I expect them to deliver on the promise.

As for variables in the real world, the same is true for fuel economy, estimated sheet yield for printer cartridges, laptop charge duration, and many other product metrics. The intent is never perfect expectation, instead serving as what amounts to a relative spitball reference. I know that you’re plenty aware of this. None among us looks at an edge retention test and walks away with a vision of cutting exactly X amount of cardboard or rope.

Part of my ownership experience is feeling good about getting what I paid for, and I have yet to meet anybody who bought M390 with the expectation that it would behave like S30V, or worse, that it might dull in 35 feet of cardboard cutting because the process was blown.

I’m not trying to be hostile here, just engaging in respectful conversation. I know who you are, and am thankful for your presence in the community. I hope that comes through clearly.

Can you tell the difference in M390 and S30V in real world use?

They are actually pretty close performance wise depending.

I think that's a portion of the problem.

Yeah it's one of the mid range steels, S35VN, S30V, CPM 154, ELMAX and M390, they all are really close enough performance wise depending that it can be hard to tell the difference in them in real world use.

I agree, but if they were all unleashed to (close to) their max potential, would the difference not become more noticeable? IIRC M390 has the potential to outperform (and I'm going to use a subjective term..... NOTICEABLY) in almost every way.

[Ankerson]

Can you tell the difference in M390 and S30V in real world use?

They are actually pretty close performance wise depending.

I think that's a portion of the problem.

Yeah it's one of the mid range steels, S35VN, S30V, CPM 154, ELMAX and M390, they all are really close enough performance wise depending that it can be hard to tell the difference in them in real world use.

I agree, but if they were all unleashed to (close to) their max potential, would the difference not become more noticeable? IIRC M390 has the potential to outperform (and I'm going to use a subjective term..... NOTICEABLY) in almost every way.

Would still be the same thing, they all are actually pretty close, I have tested them all in customs with excellent HT's and in real use they all are very close.

Close enough that it can be hard to tell the difference in real use.

You really have to jump to the next level to see absolute differences, comparing them to S110V, CPM 10V, S90V etc.

[Banter 247]

re: a knife dulling in 35 feet when properly sharpened— it was sharpened by a very experienced sharpener, for testing, using the same progression he uses for every test, and got about 9% as far as M390 tested at 62hrc. We have contacted the manufacturer, as the sample is one of multiples hit around 50hrc.

As for S30V vs M390, and whether I’d notice the difference: that’s my point. I do a lot of cutting. Comparing S30V at typical production ranges (58-60 hrc) and M390/20CV/204P at 60-62, yeah. The difference becomes appreciable. 58-60 vs 58-60? I’ve made the same argument myself, many times, and it’s why we’re here talking about running M390/20CV/204P at a range where it differentiates.

[Ankerson]

re: a knife dulling in 35 feet when properly sharpened— it was sharpened by a very experienced sharpener, for testing, using the same progression he uses for every test, and got about 9% as far as M390 tested at 62hrc. We have contacted the manufacturer, as the sample is one of multiples hit around 50hrc.

As for S30V vs M390, and whether I’d notice the difference: that’s my point. I do a lot of cutting. Comparing S30V at typical production ranges (58-60 hrc) and M390/20CV/204P at 60-62, yeah. The difference becomes appreciable. 58-60 vs 58-60? I’ve made the same argument myself, many times, and it’s why we’re here talking about running M390/20CV/204P at a range where it differentiates.

If it's at 50 HRC that's a problem.

Yeah contact the maker.

But then another could be 62 HRC with a blown grain that will perform even worse than the 50 HRC blade.

There is much more to it than just the HRC number, you could fill books with all the variables on heat treating, and there are plenty of books on it.

Could also take a blades, both at 62 HRC, one HTed for better corrosion resistance or toughness than the other.

[Pelagic]

Big Brown Bear has made some comments about 64HRC not being out of range for m390, assuming it still has adequate strength/stability. I'm no metallurgist but I believe that is far out of s30v's capacity. I could be wrong. But the whole thing is about bringing out this steel's potential. Partially because of its cost and the hype surrounding it.

Basically addressing the question of "why are we paying premium costs for this steel, which has so much hype and popularity behind it, when there is so much performance left on the table?" As you said in a number of production level comparisons there isn't much difference between m390 and s30v, even in some customs. And this of course applies to spyderco (who seems to have a good HT on m390/204p/20cv) much less than most other companies.

[Ankerson]

Big Brown Bear has made some comments about 64HRC not being out of range for m390, assuming it still has adequate strength/stability. I'm no metallurgist but I believe that is far out of s30v's capacity. I could be wrong. But the whole thing is bringing out this steel's potential. Partially because of its cost and the hype surrounding it.

In customs.... Done by a maker who does their own heat treating making one blade at a time and really knows what they are doing and can thread the needle. Assuming that's it's a batch of steel that can actually be taken to 64 HRC.

That's apples and oranges however.

You can't compare customs to production blades.

Spyderco is very picky about their heat treating and performance of their knives so yes they will actually perform well, better than most normally.

Sal and Eric are very stiff necked about what they want out of their knives.

They do extensive testing BEFORE the models are released.

[Pelagic]

Big Brown Bear has made some comments about 64HRC not being out of range for m390, assuming it still has adequate strength/stability. I'm no metallurgist but I believe that is far out of s30v's capacity. I could be wrong. But the whole thing is bringing out this steel's potential. Partially because of its cost and the hype surrounding it.

In customs.... Done by a maker who does their own heat treating making one blade at a time and really knows what they are doing and can thread the needle. Assuming that's it's a batch of steel that can actually be taken to 64 HRC.

That's apples and oranges however.

You can't compare customs to production blades.

Spyderco is very picky about their heat treating and performance of their knives so yes they will actually perform well, better than most normally.

Sal and Eric are very stiff necked about what they want out of their knives.

They do extensive testing BEFORE the models are released.

I agree with all that. I wasn't trying to make a production vs custom comparison. I was under the impression that usually, if m390 is better than s30v when both have optimal heat treats, then m390 should be better than s30v on a production level as well (oranges vs oranges as to apples vs apples). But apparently they are far to similar to warrant the difference in price we see in the knife world??

[Banter 247]

re: a knife dulling in 35 feet when properly sharpened— it was sharpened by a very experienced sharpener, for testing, using the same progression he uses for every test, and got about 9% as far as M390 tested at 62hrc. We have contacted the manufacturer, as the sample is one of multiples hit around 50hrc.

As for S30V vs M390, and whether I’d notice the difference: that’s my point. I do a lot of cutting. Comparing S30V at typical production ranges (58-60 hrc) and M390/20CV/204P at 60-62, yeah. The difference becomes appreciable. 58-60 vs 58-60? I’ve made the same argument myself, many times, and it’s why we’re here talking about running M390/20CV/204P at a range where it differentiates.

If it's at 50 HRC that's a problem.

Yeah contact the maker.

But then another could be 62 HRC with a blown grain that will perform even worse than the 50 HRC blade.

There is much more to it than just the HRC number, you could fill books with all the variables on heat treating, and there are plenty of books on it.

Could also take a blades, both at 62 HRC, one HTed for better corrosion resistance or toughness than the other.

Indeed. My point isn’t that hrc is the be all, end all. I’ve made it a specific point to highlight that it *isn’t* when talking about it, for exactly the reasons you list. Rather, my perspective is that it is *a* thing, as opposed to *the* thing.

[Pelagic]

To me, this seems like building an engine that's meant for 18psi of boost and only feeding it 10psi. It's fast. It beats almost anything you'll come across. It works fine. But feeding it 12psi won't have any noticeable effect on longevity and simply performs better.

And in this analogy the gear heads are the knife afi's.

[Ankerson]

Big Brown Bear has made some comments about 64HRC not being out of range for m390, assuming it still has adequate strength/stability. I'm no metallurgist but I believe that is far out of s30v's capacity. I could be wrong. But the whole thing is bringing out this steel's potential. Partially because of its cost and the hype surrounding it.

In customs.... Done by a maker who does their own heat treating making one blade at a time and really knows what they are doing and can thread the needle. Assuming that's it's a batch of steel that can actually be taken to 64 HRC.

That's apples and oranges however.

You can't compare customs to production blades.

Spyderco is very picky about their heat treating and performance of their knives so yes they will actually perform well, better than most normally.

Sal and Eric are very stiff necked about what they want out of their knives.

They do extensive testing BEFORE the models are released.

I agree with all that. I wasn't trying to make a production vs custom comparison. I was under the impression that usually, if m390 is better than s30v when both have optimal heat treats, then m390 should be better than s30v on a production level as well (oranges vs oranges as to apples vs apples). But apparently they are far to similar to warrant the difference in price we see in the knife world??

In testing yes... that's actual measured testing using a known format that has repeatable results and narrows down the variables.

In real world use?

Not so much depending, not enough that the other variables wouldn't make a larger difference affecting the perception of performance.

M390 costs more money for the raw steel, that's why the knives cost more.