Short term performance versus long term performance

Nathan, that knife was custom made and heat treated for you. Otherwise, I probably would have tempered it down just a bit more. I know you won't "abuse" it. Glad you like it.

For those that don't know, I also have a knife of Nathan's and use it as one of my shop knives. I've really really put it to the test, bordering on abuse, because Nathan asked me to. It's holding up great and a pleasure to use.

I think the long term performance also has a lot to do with the balance and feel of a knife, not just blade geometry and HT. The balance and feel are at least equally important as anything else with any "hand tool".
 
How can we as knife makers estimate long term performance?
This question came to me when I was preparing to test a WWII Japanese sword to destruction. Talking to Wayne Goddard and a few metallurgists suggested that retained austenite could and would over time convert to untempered martensite which would be brittle, thus testing a blade over 40 years after it was made would not be an inclusive test of the blades performance qualities at the time it was made. Thus if we could heat treat in such manner as to convert as much retained austenite in our blades as possible we would probably ensure greater longevity in our blades. Retained austenite in a blade is easily evaluated via microscopic examination of a cross section of the blade.

I will not live long enough to test one of my blades 40 years from now, but we have been able to lower the retained austenite in our blades to the point that there is no measurable retained austenite in the hardened portion.

This is part of my answer to your question. We need to study knives made comparatively long ago, ask why they failed, compare our thoughts with the science of metals and search for answers.

I fully agree that the ABS testing is simplistic, know that a mild steel blade has passed the performance testing for one man seeking his journeyman stamp as his personal protest to the limits of the existing performance tests. I feel that is it preposterous that in over 30 years the ABS the performance testing remains essentially the same as it was when Bill Moran laid the guidelines down.

Performance is up to each one of us to seek the best we can develop in our knives.
 
This is slightly tangential to the subject, but it keeps coming up in the conversation.

There seems to be a tendency for people to think of the uneducated public as idiots or sheeple. That's really unfortunate. In any field with a sufficient level of specialization there will be a spectrum of knowledge from none at all to expertise. Those on the lower end of the spectrum aren't necessarily stupid, they just focus their expertise in other areas. When it comes to areas in which they are not expert, they rely on the knowledge of others, and their ability to present that knowledge in a way that "sticks" with them.

If the tendency with high end cutlery is being swayed by people using flashy sales messaging, those salesmen are demonstrating a skill most technicians don't have... the ability to create "sticky" messages. "My knives are better because they can take this abuse and still retain a lifetime warranty," for example.

The fact that you know the message is crap derives from your knowledge of the craft. But if you have a better product, what stops you from crafting a better "sticky" message? For one thing, your expertise at making quality knives doesn't necessarily translate into expertise at marketing. Doesn't mean you're stupid or a sheeple, you just focus your expertise elsewhere.

The point of this rant (yes, there is one) is that we need to be a bit more respectful of the people that might eventually be customers... if we have the ability to get our message through to them. If we (personally) don't have the skill to craft that message, maybe we should employ someone who does... even if that someone doesn't know beans about knives.

In the end, if long term performance is more important to the determination of the quality of a knife, someone needs to find a qualitative means of demonstrating that... something that can compete with the "lifetime warranty" of a Ginsu, for example. Something, perhaps, that resonates in the mind the same way cutting a cinder block does.

If we can't convince people that long term performance IS the determining factor, then like it or not, we may be wrong about that. Maybe they are right, and maybe it is more socially accepted (and satisfying) to simply replace the dull Henckels. Maybe that isn't a sign of stupidity after all, but a socially conscious thing to do as it keeps some knife makers employed.

Be careful of assuming you're always right. I'm sure you always are... but just in case someone else is a little MORE right, you might want to be flexible.

- Greg
 
Good point about the RA Ed. I don't think we can accurately estimate long term performance, because of the inherent instability and unpredictability of steel,… but we can be real careful about any sorts of "delayed reactions", RA, internal stresses etc., which could shorten the life of our blades.
 
Thanks Tai:
I well remember my experience with stress in a blade. I once ground out a fighting style blade out of a file many years ago before I knew anything about stress in a blade. I ground out the blade , keeping it cool so as to keep it hard. It was a beauty, hung on my kitchen wall for years, then one day it broke with a bang and 1/2 of the blade fell to the floor. Accidentally I had created stress in the blade when grinding and over time they overcame the strength of the file steel.

It was a real learning experience for me.
 
Ed, I once had something like that happen on a folder I bought, made by another maker. It was a water quenched leaf spring blade with a minimal temper. It performed great for several years. Finally, I decided to just retire it to my display case and test some other knives. It sat in the display case for 5-6 years. I got it out one day to look at it and noticed that it had several cracks along the edge,... just from sitting in the case.
 
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