13 Myths about Heat Treating Knives

[Karl H]

Actually, yes. They've had a "bad reputation" for under-hardening for a long time. I doubt that the lost performance is a significant factor for their core customer base and might provide some benefits (e.g. easier sharpening/less chipping), but for the spec junkies who care about the hardness and are already used to harder blades it's a turn-off.

How do they get a "bad reputation" for accurately disclosing their 59-60 RC hardness range? The disclosure saves the people who want their steel to be harder than 59-60 HRC from wasting their time and money.

It's good that Spyderco provides good warranty support, but I think most people would rather know when they are getting a low-toughness blade that is susceptible to chipping or breaking. To my knowledge, Spyderco has had cases of Maxamet, S110v, and ZDP-189 blades chipping or breaking under normal use.

 

[Larrin]

There has definitely been a creep upward in hardness over the past couple decades. 59-60 Rc was not considered low at the time that S30V came out.

 

[Danke42]

I don't understand what point you are trying to make. The primary defense against people posting inaccurate test data about your products is to provide your own accurate test data.

Larrin's points about the shortcomings of hardness testing is essentially a recommendation to do additional types of testing to better optimize a heat treatment process. I understand that hardness test data is not the only or the best possible measure of steel performance, but it is better than having no measure of performance, and it is significantly cheaper and easier to perform than other types of standardized performance testing.

If knife makers published tensile test data, compression test data, or toughness test data, then I would use it to make better informed purchasing decisions. However, I have yet to see any knife maker publish any measure of steel performance other than hardness. So, in lieu of having any other type of performance test data available, consumers that care about steel performance are understandably going to focus on hardness. If the knife maker doesn't publish any test data, consumers will look to third parties for that information.

The point is that it doesn't matter.

Folks that chase HRC are like people who chase megapixles in cameras. They want an easy to say and hopefully big impressive number to show their friends.

 

[Karl H]

The point is that it doesn't matter.

Folks that chase HRC are like people who chase megapixles in cameras. They want an easy to say and hopefully big impressive number to show their friends.

It is disingenuous to say that hardness doesn't matter. Why do you think that people no longer use knives made from bronze or low-carbon steel? Why do you think knife makers bother with heat treating knives? There are people who foolishly chase hardness to the exclusion of all else, but that is hardly a significant majority of knife buyers.

I believe that the single greatest reason that people chase hardness is because knife manufacturers don't disclose toughness test data. They don't understand the tradeoffs. Or perhaps they do understand the tradeoffs, but assume that a "reputable" manufacturer wouldn't sell them a knife that would chip or break.

 

[dirc]

There has definitely been a creep upward in hardness over the past couple decades. 59-60 Rc was not considered low at the time that S30V came out.

what I want to know is where I can get some 52100+.2%V?? it sounds pretty excellent

thanks for the excellent write up, seriously

 

[Danke42]

It is disingenuous to say that hardness doesn't matter. Why do you think that people no longer use knives made from bronze or low-carbon steel? Why do you think knife makers bother with heat treating knives? There are people who foolishly chase hardness to the exclusion of all else, but that is hardly a significant majority of knife buyers.

I believe that the single greatest reason that people chase hardness is because knife manufacturers don't disclose toughness test data. They don't understand the tradeoffs. Or perhaps they do understand the tradeoffs, but assume that a "reputable" manufacturer wouldn't sell them a knife that would chip or break.

Previous editions of this same conversation all devolved to the IG crowd wanting to bash other peoples knives.

As said there are makers who'll build you special to order high hardness knives. You just have to pay for it.

Expecting production companies to all open their books out of the kindness of their hearts on this and just share the data is unlikely.

 

[K-Lastima]

Thank you for the reading material.

 

[Larrin]

what I want to know is where I can get some 52100+.2%V?? it sounds pretty excellent

thanks for the excellent write up, seriously

It is called L3, I labeled it differently so people would know what it is. It seems to have been more available way back in the day.

 

[Karl H]

There has definitely been a creep upward in hardness over the past couple decades. 59-60 Rc was not considered low at the time that S30V came out.

I did a little bit more research on the CRK hardness hoopla.

It appears that Anne Reeve, one of the owners of CRK, stated in 2015 that they made this change from 58-59 HRC to 59-60 HRC around 2013, but some products were shipped with documentation/birth cards mis-marked as having the old, lower HT standard. So, I would assume that the original S35VN heat treatment spec was 58-59 HRC. From what I can tell, the heat treatment spec for CRK S30V was always 58-59 HRC. I don't know when CRK started to disclose the hardness of their knives.