I Tested the Edge Retention of 48 Steels

For instance, the 14C28N I've had closer to 60HRC is pretty good. The 14C28N I've had closer to 56HRC doesn't seem to take as hard a nosedive as M390 does when run soft. (Hardness isn't everything but it is something.) Maybe Larrin Larrin could talk a bit more about this?



What if the differences you're seeing is just scatted anecdotal evidence rather than specifically M390 at lower hardness being worse than 14C28N at lower hardness?

What would be a good test to quantify the "nose dive" you experienced so we could compare the differences with more objective data to see this behavior?
 
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What if the differences you're seeing is just scatted anecdotal evidence rather than specifically M390 at lower hardness being worse than 14C28N at lower hardness?

What would be a good test to quantify the "nose dive" you experienced so we could compare the differences with more objective data to see this behavior?

From the imaginary graph of anecdotal values, the top of the curve is part of what makes the nose dive. 😜

Expectation is a part of it. Looking at production knives, how much of the D2 or M390 on the market really lives up to expectations? Looking at Larrin's values, wherein M390 has an edge retention value of 6.5 and 14C28N has a value of 3, does that compare with real-world use of these steels for the majority of production knives using those steels?

From the other side, I've previously raised the issue that 14C28N and 8Cr13Mov are both rated "3" while 440A is rated "3.5". In real-world applications with actual production knives running those steels, I've found 14C28N to be much better than either. Of course, heat treatment matters and I wouldn't expect an ideal heat treatment on a $15 folder. Another thing is that choices have to be made in modeling or testing conditions. They might not match personal experience or perception. For instance, a big reason people hate on 8Cr13Mov isn't that it goes totally dull but that it is easy to get a "screaming sharp" fine edge but it quickly degrades to a ho-hum working edge.
 
From the imaginary graph of anecdotal values, the top of the curve is part of what makes the nose dive. 😜

Expectation is a part of it. Looking at production knives, how much of the D2 or M390 on the market really lives up to expectations? Looking at Larrin's values, wherein M390 has an edge retention value of 6.5 and 14C28N has a value of 3, does that compare with real-world use of these steels for the majority of production knives using those steels?

From the other side, I've previously raised the issue that 14C28N and 8Cr13Mov are both rated "3" while 440A is rated "3.5". In real-world applications with actual production knives running those steels, I've found 14C28N to be much better than either. Of course, heat treatment matters and I wouldn't expect an ideal heat treatment on a $15 folder. Another thing is that choices have to be made in modeling or testing conditions. They might not match personal experience or perception. For instance, a big reason people hate on 8Cr13Mov isn't that it goes totally dull but that it is easy to get a "screaming sharp" fine edge but it quickly degrades to a ho-hum working edge.



If we did a blind test where nobody knew what the steel or hardness was, would they all come to the same conclusions as you with the same testing that led to your conclusions?

Seems like there would be a lot of subjectivity without some kind of more objective test that produces some form of data for us to compare?

Whether folks agree or disagree about the steel ratings, we can trace the rating back to an actual test that was done that produced data for the rating.

The ratings are a steel test.

The steel is only one component for a knife test.
Who is to say that your experiences are or aren't more based on the knife than just purely the steel?

The differences in real world to the steel ratings can also be due to scatter from the subjective nature people are experiencing their KNIVES (not steel itself ) and only through small "snapshots" of anecdotal experiences without much thought for other variables that have a huge influence besides the name of the steel.

For example, I don't see a lot of people using laser edge Goniometers to rule out geometry for either edge retention or durability yet that's the first thing that needs to be ruled out.


Prior to the steel ratings we had graphs and charts that were based off of people's subjective feelings. A maker would pass it around to different people and have them arange the steels based off of their "experiences" It was quite a confusing mess that wasn't based off of anything and led to a lot of confusion even though everyone's hearts were in the best place.

What would you recommend as an experiment to test your theory?
 
If we did a blind test where nobody knew what the steel or hardness was, would they all come to the same conclusions as you with the same testing that led to your conclusions?

Seems like there would be a lot of subjectivity without some kind of more objective test that produces some form of data for us to compare?

Whether folks agree or disagree about the steel ratings, we can trace the rating back to an actual test that was done that produced data for the rating.

The ratings are a steel test.

The steel is only one component for a knife test.
Who is to say that your experiences are or aren't more based on the knife than just purely the steel?

The differences in real world to the steel ratings can also be due to scatter from the subjective nature people are experiencing their KNIVES (not steel itself ) and only through small "snapshots" of anecdotal experiences without much thought for other variables that have a huge influence besides the name of the steel.

For example, I don't see a lot of people using laser edge Goniometers to rule out geometry for either edge retention or durability yet that's the first thing that needs to be ruled out.


Prior to the steel ratings we had graphs and charts that were based off of people's subjective feelings. A maker would pass it around to different people and have them arange the steels based off of their "experiences" It was quite a confusing mess that wasn't based off of anything and led to a lot of confusion even though everyone's hearts were in the best place.

What would you recommend as an experiment to test your theory?

Hey. Don't get me wrong. I'm not complaining about getting good data points, testing under reasonably standardized conditions, comparisons based on more reliable testing, etc. Those are good things!

I'm pointing out that (1) tests test particular samples under particular conditions and report specific things, (2) those tests may or may not mirror real-world conditions, user experiences, etc.; and (3) some specific observations about the performance of certain steels as used in budget-oriented or competitively priced production knives.

It's not just me or my subjective experiences either. Similar results as those mentioned in my previous post have been reported by Super Steel Steve, Outpost 76, and others. Of course, they all have their own conditions too. Now, is there a question about my observations in 3 or do you have different observations you'd like to share?
 
Remember again that heat treatment matters. Just because a steel is capable of amazing edge retention, and scores highly with Larrin's heat treatment under his testing conditions, does not mean that it will be the same in a production knife under your personal use conditions. For instance, 14C28N with a very good heat treatment versus S35VN with a much less good heat treatment can be closer than people might expect.

I'm not a metallurgist but it seems to me that some steels are easier to get right, do better in mass-production heat treatment, or are less sensitive to issues in heat treatment. For instance, the 14C28N I've had closer to 60HRC is pretty good. The 14C28N I've had closer to 56HRC doesn't seem to take as hard a nosedive as M390 does when run soft. (Hardness isn't everything but it is something.) Maybe Larrin Larrin could talk a bit more about this?
Unless the heat treat is screwed up, which is possible, but is not really worth talking about, steels behave in predictable ways and similar to how they perform in real, scientific tests. User experiences with different knives are so biased by other attributes that comparing steels based on user experiences with different knives is at best a rough guideline and at worse useless. Given enough user experiences one could probably get a sense of performance categories, but it is too optimistic to think that one could reasonably make quality judgements on particular steels, especially steels that fall in the same range of performance. Hardness doesn’t in itself tell you how the steel got there as you can have steel at the same hardness that performs differently, given this you can’t say that one steel takes a larger ”nose dive” vs the other.
 
Hey. Don't get me wrong. I'm not complaining about getting good data points, testing under reasonably standardized conditions, comparisons based on more reliable testing, etc. Those are good things!

I'm pointing out that (1) tests test particular samples under particular conditions and report specific things, (2) those tests may or may not mirror real-world conditions, user experiences, etc.; and (3) some specific observations about the performance of certain steels as used in budget-oriented or competitively priced production knives.

It's not just me or my subjective experiences either. Similar results as those mentioned in my previous post have been reported by Super Steel Steve, Outpost 76, and others. Of course, they all have their own conditions too. Now, is there a question about my observations in 3 or do you have different observations you'd like to share?

Help me understand.

In your subjective experiences M390 and 14C28N at low hardness will show that M390 takes a "nose dive?"

is that correct?

What does "nose dive" mean more specifically?
What happens?

Have to get more specific for a better discussion.
 
Help me understand.

In your subjective experiences M390 and 14C28N at low hardness will show that M390 takes a "nose dive?"

is that correct?

What does "nose dive" mean more specifically?
What happens?

Have to get more specific for a better discussion.

So for modesty, imagine that you have a rocket of expectations aimed at the numbers on Larrin's chart. (We'll excuse shooting for the moon on super steel fantasies.) You see that cool new knife with "M390", "Elmax", or whatever awesome-sauce super steel printed on the blade. You go to use it, and I don't just mean on a weekend over a few Zima Ice. You use it over time, sharpening it at least a few times, maybe adjusting the angle, and hopefully enjoying a few real beers along the way.

So did that rocket ultimately hit the target of your expectations, based on whatever test, chart, or what someone said here? Did it hit higher than expected or did it come in lower than you had hoped? Did you get that super steel with a "meh" heat treatment that caused it to take a nose dive and land in the ballpark of lesser steels?

Obviously, steels with higher ratings have more room to fall and some occasionally do. Within the last few years, we've seen issues pop up with both production M390 and the flood of Chinese D2. Whether it's Super Steel Steve swearing up a storm, Outpost 76 carefully using his KME and running a 1" section through cardboard, or Pete doing his AUS-8 vs. D2 Rat challenge on rope; there is information besides my feelings at the recycling bin. The metallurgical question I was asking was about the ease of getting a good heat treatment on some steels versus others, or whether certain steels are more sensitive to issues in heat treatment than others.

Personally, the edge retention of 14C28N in budget knives tends to meet or exceed expectations relative to its ratings and similarly rated steels. Even in knives where they might be running it softer, it never seems to suck all that hard relative to its rating or general expectations. That's not to say it can't suck. Those are just my experiences and they seem to be mirrored in some of the kinds of testing I referencing.
 
So for modesty, imagine that you have a rocket of expectations aimed at the numbers on Larrin's chart. (We'll excuse shooting for the moon on super steel fantasies.) You see that cool new knife with "M390", "Elmax", or whatever awesome-sauce super steel printed on the blade. You go to use it, and I don't just mean on a weekend over a few Zima Ice. You use it over time, sharpening it at least a few times, maybe adjusting the angle, and hopefully enjoying a few real beers along the way.

So did that rocket ultimately hit the target of your expectations, based on whatever test, chart, or what someone said here? Did it hit higher than expected or did it come in lower than you had hoped? Did you get that super steel with a "meh" heat treatment that caused it to take a nose dive and land in the ballpark of lesser steels?

Obviously, steels with higher ratings have more room to fall and some occasionally do. Within the last few years, we've seen issues pop up with both production M390 and the flood of Chinese D2. Whether it's Super Steel Steve swearing up a storm, Outpost 76 carefully using his KME and running a 1" section through cardboard, or Pete doing his AUS-8 vs. D2 Rat challenge on rope; there is information besides my feelings at the recycling bin. The metallurgical question I was asking was about the ease of getting a good heat treatment on some steels versus others, or whether certain steels are more sensitive to issues in heat treatment than others.

Personally, the edge retention of 14C28N in budget knives tends to meet or exceed expectations relative to its ratings and similarly rated steels. Even in knives where they might be running it softer, it never seems to suck all that hard relative to its rating or general expectations. That's not to say it can't suck. Those are just my experiences and they seem to be mirrored in some of the kinds of testing I referencing.

This seems like a separate topic then the question I asked?

This post seems to be about expectations?

So, with M390 and 14C28N at low hardness, M390 takes a "nose dive" in expectations?
 
This seems like a separate topic then the question I asked?

This post seems to be about expectations?

So, with M390 and 14C28N at low hardness, M390 takes a "nose dive" in expectations?

I'd say that M390, if not done well, takes a more significant nose dive in the realization of potential and in diverging negatively from expectation.
 
I guess I don't quite understand the disagreement/line of questioning. I am curious, for those that may know (BBB certainly would).

1. Are there steels that are easier to heat treat? Phrased another way, are there steels that are more "forgiving" if a precise heat treat protocol is not followed exactly?

2. Are there steels that are more "forgiving" (in the manner I used that term above) with respect to the issues facing large production heat treating? For example, if precise temperature control is harder with large batches, are there steels that require less precise temperature control, and are thus easier to heat treat in large batches?

Assuming there are some such steels (and acknowledging other caveats noted), it seems reasonable to postulate that such steels would be less affected by the practices attendant to large scale production. In other words, it seems such steels would take less of a "nose dive" in performance as a result of the issues facing large scale production heat treating.

As always, appreciate all the information shared here. This is an awesome thread.
 
Expectations are totally subjective and can be influenced by personal opinions, the biases of individual preference (i.e., "cool factor"), or even how much someone spent on a knife. They're useless as a reliable measurement.

Forming expectations from quantified, measured results during a very specific use case, and then saying your expectations weren't met when using a knife/steel for something totally different, which wasn't measured or quantifiable, has no real merit. If your expectations aren't met, it's likely a problem with your understanding of what was illustrated in a controlled test.

Controlled tests show the properties of steels when most other things are equal or accounted for to some degree. This will never be the case in a real use scenario, especially if we're comparing different knives with different edge geometries, heat treatments, unknown hardnesses, etc.

You can't accurately compare this steel to that steel without a lot of work, which most of us are totally unwilling to do.
 
Help me understand.

In your subjective experiences M390 and 14C28N at low hardness will show that M390 takes a "nose dive?"

is that correct?

What does "nose dive" mean more specifically?
What happens?

Have to get more specific for a better discussion.
Low published HRC = 2.3 likes on Instagram
High published HRC = 56792.7 likes on Instagram
 
mine is, it confirms to me how great a value aeb-l & 14c28n are for stainless ingots... & just all the other data, being able to choose the best mix of properties for the design

but of course the real take away is the excellent knowledge, time & research & work that went into this - again kudos to Larrin Larrin & everyone who helped
 
If this had been asked/ answered I apologize but I would like to know who is Heat treating magnacut to its potential, as Lorrin intended.
I ask because it's seams many manufacturers tend to go a little soft on many steels.
 
If this had been asked/ answered I apologize but I would like to know who is Heat treating magnacut to its potential, as Lorrin intended.
I ask because it's seams many manufacturers tend to go a little soft on many steels.

Don't get too caught up in a steel needing to be a specific HRC to perform well.

The subject is much more complex, especially when we start asking questions about microstructure.

Don't get me wrong, It needs sufficient hardness and certainly can't be under 60rc for a small knife but if it's in the range of 62 to 64rc, that's more than enough to "experience" MagnaCut from any of the reputable brands.

You should think of HRC like body weight.

While there is a correlation of higher strength with higher amounts of bodyweight. It is the body composition not just the weight itself that is a more accurate predictor of strength.

Yes, there can be folks at lower body weights that can be stronger than people with higher body weights.

Similarly with steel there can also be some cases where 63rc can be stronger than 64rc due to the composite nature of the constituents in the microstructure.


If you want the extreme hardness limit unfortunately It's not something you'll find in a production knife and you'll have to move towards a small batch custom knife maker and do some research on that maker's priorities and capabilities.

Just keep in mind, MagnaCut at 64-65rc is not going to outcut everything.

It is designed to be a balanced steel, a stainless CPM 4V which is quite revolutionary because we've never had a crossover between PM stainless and PM tool steels.

So, hopefully this information can help you manage your expectations without hype.

It is certainly a very enjoyable material to use and sharpen.
 
I currently only have one magnacut knife. A Decka. I understand higher is not better but it should preform best within it's intended range.Right? Does Hogue heat treat in this range. 62 rc +- 1 if I'm not mistaken.
 
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