01-13-2018, 05:10 PM
(This post was last modified: 01-13-2018, 05:14 PM by Mark Reich.)
Unfortunately for me, I find about 98% of Dr. Verhoeven's writing doesn't really apply to me, directly. Not that it isn't interesting, and helps discussing things with proper terminology, and gives you some guidelines.
In fact, the only source of information specific to me, in my shop, using my equipment, has been generated by me. I think a lot bladesmiths are likely to feel that way. There are just too many variables. It's very similar to reloading high power ammunition. As a rule, shooters won't use the same load in seemingly identical firearms.
I've heard of full hardened 52100 at temps as low as 1430°, held for an hour. Likewise, I don't often hear of 1 hour tempering cycles, but I'm certainly not going to second guess your methods.
I just expect the average EDC blade will break long before you get to 45°. Means nothing to me. I actually own a couple hundred knives like that. I didn't make them.
Destruction testing doesn't apply to kitchen knives remotely as much as it would EDC knives, or hunting/survival knives.
I generally consider all my non-kitchen knives to be survival knives, and I damn sure want to know exactly what to expect out of them. Bolting a large torque wrench to a blade held in an immoveable vice, and measuring strength at 45°-90° flexes is the only way I can guarantee my knives will perform acceptably To Me.
If a blade is capable of a 90° flex or two, how likely is that knife to break- no matter what? That's the point. No matter what. Beat it with a sledgehammer, If You Have To. I know it won't break.
Yes, blade geometry is a large factor, especially when your blade is 1/16" thick. Or 1/4" thick, but nowhere near as important as differential heat treating an average 1/8" thick blade. I expect one of my "average" blades to flex to 45° and spring back most of the way immediately. If I leave it sitting there in the vise overnight, I expect it to keep straightening. I expect that to keep happening many many times.
I don't expect anyone except HEPK bladesmiths to continuously test knives like this. Nobody HAS to. I WANT to, especially with any blade that isn't almost perfect.
I Expect that to mean nothing to anyone else... unless you're buying a knife from me.
In fact, the only source of information specific to me, in my shop, using my equipment, has been generated by me. I think a lot bladesmiths are likely to feel that way. There are just too many variables. It's very similar to reloading high power ammunition. As a rule, shooters won't use the same load in seemingly identical firearms.
I've heard of full hardened 52100 at temps as low as 1430°, held for an hour. Likewise, I don't often hear of 1 hour tempering cycles, but I'm certainly not going to second guess your methods.
I just expect the average EDC blade will break long before you get to 45°. Means nothing to me. I actually own a couple hundred knives like that. I didn't make them.
Destruction testing doesn't apply to kitchen knives remotely as much as it would EDC knives, or hunting/survival knives.
I generally consider all my non-kitchen knives to be survival knives, and I damn sure want to know exactly what to expect out of them. Bolting a large torque wrench to a blade held in an immoveable vice, and measuring strength at 45°-90° flexes is the only way I can guarantee my knives will perform acceptably To Me.
If a blade is capable of a 90° flex or two, how likely is that knife to break- no matter what? That's the point. No matter what. Beat it with a sledgehammer, If You Have To. I know it won't break.
Yes, blade geometry is a large factor, especially when your blade is 1/16" thick. Or 1/4" thick, but nowhere near as important as differential heat treating an average 1/8" thick blade. I expect one of my "average" blades to flex to 45° and spring back most of the way immediately. If I leave it sitting there in the vise overnight, I expect it to keep straightening. I expect that to keep happening many many times.
I don't expect anyone except HEPK bladesmiths to continuously test knives like this. Nobody HAS to. I WANT to, especially with any blade that isn't almost perfect.
I Expect that to mean nothing to anyone else... unless you're buying a knife from me.