HRC Database

[Woodpuppy]

The explanation about deviating from ASTM is absolutely relevant, and in my opinion would have been appropriate to include in your initial comment. There is much we enthusiasts don’t know, while we argue about what steel and handle material is “best”.

[u.w.]

https://youtu.be/4dho02LIZU8

A lot of his knives are Spydercos. Sounds interesting.

Looks like he needs a refresher on the standard practices and procedures and how to straighten up that dial.

Pretty cocky video thumbnail for someone with little reading and experience with hardness testing.

Looks like we're going to get all kinds of wacky test results as we watch Alex try to reinvent the wheel.

Perhaps not a great "look" Shawn.

I'm left wondering: How do you know how much reading experience he has?

And in regards to "wacky test results", he says he calibrated the tester prior to doing the knife in that video; and in the next video, he shows some of that, with the cal'd/test(er) plates.

(If I've got my head up my ..., don't spare my feelings, and please enlighten me. I'll hopefully be smarter for it, and I'll still luv ya. We're both long since grown)

That said, what is it he's is not doing correctly? Constructive criticism vs. just Criticism. Me personally - I'll take Both, but I am curious as to what he is doing wrong?


u.w.

Is it a better look to censor knowledge? There's nothing stopping anybody from learning how hardness testing works and from getting a copy of the ASTM 18-20 to understand what the best practices are for the most accurate results.

I don't want to be that guy to call people out.

Keep in mind, I don't have to share and for the most part I keep to myself.

But if somebody is misinforming people whether it's through negligence, ignorance or incompetence,

Wouldn't you like it if somebody with the knowledge said something?

Perhaps there's a better way on my part to bring this up but sometimes it's nice to be direct.

In my opinion - No, definitely not a better look to censor knowledge. Was unaware of what the "pub" (publication) for hardness testing was, which is kinda funny, considering one of my past jobs.. Thank you for posting what it is.

We share the trait of keeping mostly to ourselves then, as I'd bet a whole lot of others do too. And, I hope that trait doesn't conflict with the censoring part, self or otherwise..

Yes, I would absolutely like, or prefer, it if someone with knowledge/experience (you in this case right?) said something, If someone were misinforming people whether it's through negligence, ignorance or incompetence.

My own personal preference Is absolutely for the, do not spare the feelings, directness way, every time. I would always rather know exactly were someone stood, than maybe be wrong about it, or guess.

u.w.

[Big John]

https://youtu.be/4dho02LIZU8

A lot of his knives are Spydercos. Sounds interesting.

Looks like he needs a refresher on the standard practices and procedures and how to straighten up that dial.

Pretty cocky video thumbnail for someone with little reading and experience with hardness testing.

Looks like we're going to get all kinds of wacky test results as we watch Alex try to reinvent the wheel.

I don't see it as cocky at all. Most major knife manufacturers DO wish the HRC of their blades were kept secret, this is common knowledge. Strange choice of words.

"Cone of Truth" is a strange choice of words when you don't show the calibration and are showing in the video that the ASTM E18-20 standard is not being practiced which was written to make sure that everybody who does hardness testing is on the same sheet of music paper so that our hardness values can have some form of agreement between different testers and operators. Details matter if you're using your hardness test values to call people out.

Thumbnails are designed to generate clicks. If I remember right, the youngins' these days use the term "clickbait" to describe exaggerated titles and thumbnails for videos. I don't think he was insinuating that his testing is holy scripture. It seems to me that "cone of truth" was referring to HRC testing devices in general. I have seen most of his vids and he, just like you, just seems like a nice guy doing his thing on YouTube, trying to provide some interesting content. He's never come off as overly arrogant or "cocky". If he had, I'd be inclined to interpret that title the same way you did. I'd be willing to bet that a lot of his subscribers are average knife users or knife "newbies", so I think it's good that the importance of Rockwell hardness in cutlery is being pushed into the spotlight by him and many others. If enough people care, more manufacturers will be forced to as well.

[Big_Tex]

Curious if anyone has HRC info on 204P? Read through this thread and didn’t see much… after picking up one of the REC Manix 2’s to pair with my REC Shaman it got me wondering… thanks!

[BIGSTRETCH]

Thanks to everyone who has worked on this. I am impressed with how far Spyderco is willing to take a lot of these steels- especially some of the more “exotic” steels used on Sprint/Limited runs. One exception sticks out to me though. The Calypso jr. Super Blue is only about 61 hrc. Isn’t that particularly soft for this steel?

I know Spyderco’s Super Blue runs were immensely popular a few years back. Not an expert here by any means, just going by the charts at knifesteelnerds.com

Could someone with a bit more knowledge on the subject share their thoughts?

[BIGSTRETCH]

I believe that this is the test being referenced in the HRC list: https://youtu.be/eH1vP4bDlto

[Deadboxhero]

I believe that this is the test being referenced in the HRC list: https://youtu.be/eH1vP4bDlto

That model was not clad. So it was tested on the super blue steel.

[Maremmen Jager]

Someone knows how much is the hardness of Shaman in S90 like Knife Center exclusive?

[noeps]

I found this video with some testing: https://youtu.be/NChh3jHKSXQ
Among the claimed results is the Cruwear Micarta pm2 at about 63.5.

I was also hoping that I could persuade someone to measure either the M390 PITS or M390 SpyOpera...

[noeps]

To answer my own question, here is an instagram user who claims to have measured the m390 PITS at 59.3: https://www.instagram.com/p/Cq1Eid6s__k/

[Bemo]

This is disappointing if true for all the run. I love this design. Love it! But this is what I've heard about all the Mangiano heat treats.

[JRinFL]

That probably puts edge retention at or slightly above VG-10, but with better corrosion resistance. Seems like I can live with that compromise. For a do-all design, it seems to be an acceptable balance. YMMV.

[noeps]

Extrapolating slightly from Larrin's CATRA testing, m390 at 59-60 peforms better than VG-10. It should be more like s30v at 61-62 or XHP. Not sure how 59 hrc m390 became so loathed other than those youtubers who I thought were largely debunked and they were claiming numbers more like 50-56 hrc.

s90v has long been run at 59-60 and I haven't heard people complaining but for some reason m390 at 59-60 hrc is considered an insult.

[dull&blunt]

s90v has long been run at 59-60 and I haven't heard people complaining but for some reason m390 at 59-60 hrc is considered an insult.

My understanding is that there's a noticeable jump in performance (sharpening experience, edge stability, etc.) from M390/20CV/204P at 61+ compared to 58-60. People expect the best performance when they're paying for a 'super steel'.
That's where most of the shouting comes from, they get upset when they hear a little more performance could have been squeezed out of their $400 knife... Personally, after reading how Dr. Thomas described M390 as a poorly designed steel and using some 20CV myself, I now avoid it.

Comparing the HRC of any two steels, like M390 and S90V, really isn't right. Each steel seems to have its own range of HRC, and inside that HRC range is where comparisons should be made if we're talking about hardness.

[noeps]

My understanding is that there's a noticeable jump in performance (sharpening experience, edge stability, etc.) from M390/20CV/204P at 61+ compared to 58-60.

Comparing the HRC of any two steels, like M390 and S90V, really isn't right. Each steel seems to have its own range of HRC, and inside that HRC range is where comparisons should be made if we're talking about hardness.

A dramatic jump in edge performance is absent in CATRA testing: https://knifesteelnerds.com/2019/10/07/ ... 90-knives/
In that test, the thirdsecond-hardest m390 did the best out of the five four tested. What source are you using that you consider more reliable than CATRA testing?

Edit: to clarify, there is a small increase in edge retention with HRC performance as noted below, but it is not enough of a difference to be clearly apparent in the head-to-head test of various m390 knives above.

If you look at Larrin's big graph of CATRA results, there is a very predictable and small increase in edge retention as HRC increases from around 60 to over 61: s30v, d2, 440c, magnacut, and s60v experience virtually identical gains from ~60 upwards. We know s90v and s30v have predictable and generally satisfactory edge retention at 59-60 hrc. Why wouldn't m390?

Rather than there being an actual jump in performance, it seems more likely to me that certain people in the knife community love to make dramatic sweeping statements about steels and stir things up out of boredom or the desire to be seen as having access to special information. It doesn't help that m390 has been hyped to death as way better than s30v, when it is essentially s30v with more corrosion resistance and a bit less toughness.

[horzuff]

Maybe this idea could be coming from two heat treating approaches and how M390 behaves with them? I mean classic low tempering or secondary hardness tempering. Maybe one of those typically results in higher hardness but it's not just the hardness that's the cause for improved performance. This is just a blind guess though

[noeps]

It is certainly possible that m390 somehow benefits from higher hardness more than other steels. It just doesn't seem very likely or like something there is any direct evidence for. In fact there is direct evidence against this hypothesis from Catra tests.

I have also heard that the higher HRC m390 is less corrosion resistant. I think it is an established fact that the ~59 hrc heat treatment is intended to maximize corrosion resistance and going harder is a tradeoff in this area. There are at least a few users on this forum who discuss patinization/rust of m390 on spyderco knives, which are often noted on this thread or elsewhere as being 61+ hrc: https://youtu.be/ZsC8X-nxpqQ

Whereas ZT's maligned soft m390 is extremely rust-resistant: https://www.bladeforums.com/threads/m39 ... 214/page-2

And of course harder = more brittle. One user here reports their m390 Manix 2, noted on youtube for being 62+ hrc, will chip "just by being looked at." One of our beloved youtube influencers, while bragging that a 62 HRC m390 spyderco is what m390 is supposed to be like, also casually mentions that they cannot figure out how to sharpen the knife, but that it's going to be really great once they can figure out how to sharpen it.

All this hrc hype seems a bit pretentious.

[Josh Crutchley]

A dramatic jump in edge performance is absent in CATRA testing: https://knifesteelnerds.com/2019/10/07/ ... 90-knives/

That test was with production folding knives with different geometries. You would need to have them all the same like Larrin does for his testing.

Quote from article: "I don’t know if we can necessarily compare the hardness trend between the lionSteel, Kershaw, and Spyderco M390 knives due to the geometry differences between them. There is still a trend with hardness but it’s hard to tell if the geometry differences or experimental scatter are drowning it out."

[noeps]

A dramatic jump in edge performance is absent in CATRA testing: https://knifesteelnerds.com/2019/10/07/ ... 90-knives/

That test was with production folding knives with different geometries. You would need to have them all the same like Larrin does for his testing.

Quote from article: "I don’t know if we can necessarily compare the hardness trend between the lionSteel, Kershaw, and Spyderco M390 knives due to the geometry differences between them. There is still a trend with hardness but it’s hard to tell if the geometry differences or experimental scatter are drowning it out."

Two of them are the same edge angle, and they get basically identical results despite very different HRC's. The other main geometrical variable, thickness behind edge, has been shown to have only a minor impact in CATRA tests with a 34 degree edge bevel: https://knifesteelnerds.com/2018/08/27/ ... stability/

Even excluding those two knives, differences in steel that are small enough to be drowned out by statistical noise (or experimental scattering as Larrin calls it) support the hypothesis that there are not big differences between the various m390 treatments tested. Even the two knives in that test that were both at 34 degrees produce nearly identical results despite a relatively large hrc difference.

[Josh Crutchley]

Two of them are the same edge angle, and they get basically identical results despite very different HRC's. The other main geometrical variable, thickness behind edge, has been shown to have only a minor impact in CATRA tests with a 34 degree edge bevel: https://knifesteelnerds.com/2018/08/27/ ... stability/

Even excluding those two knives, differences in steel that are small enough to be drowned out by statistical noise (or experimental scattering as Larrin calls it) support the hypothesis that there are not big differences between the various m390 treatments tested. Even the two knives in that test that were both at 34 degrees produce nearly identical results despite a relatively large hrc difference.

The behind the edge measurement was ommited so there's no way to know if they where truly identical. There definitely needs to be more testing done on M390 at different hardness levels. I don't really disagree with you I was just pointing out that the test had more variables than Larrins Catra tests.

Edit: I was thinking what if the bevels where ground uneven? That might effect results.