AllenC made a great point by bringing up edge geometry. But it's no quite as simple as that (you knew this wasn't going to be simple, right?
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Edge geometry is dependent on steel. So you can't just switch to talking about edge geometry, and forget talking about steel, heat treat, and application.
Here's an example. Let's use your example: you want a medium-duty EDC folder that's obscenely sharp. You can choose S30V at 59 Rc or ZDP-189 at 65 Rc. You often cut into hard materials that stress the edge. Now, ZDP-189 at 65 Rc has a very hard, strong edge, that will deform less when stressed. That means you can take edge thinner (so it performs better) relative to S30V, which is softer and weaker and as a result needs a thicker edge with more metal for support. In other words,
it's the steel type and heat treat, matched to the application, that determines the best-performing edge geometry. Now if this were a hard-use folder, you might find (say) that the ZDP-189 kept chipping out so you'd need a thicker edge, and the S30V would keep a thinner edge because it's tougher. There, same two steels, but now because the application has changed, so can the edge geometry and the steel chosen.
And, it gets worse. Let's say your ZDP-189 knife holds up well at 12 degrees per side (a VERY higih-performance edge geometry, that would be suitable for cutting only). Cliff was the first I've seen who looked at even higher-performance edge geometries, and he found that steels with big chromium carbides (stainless steels like ZDP) don't like being taken much thinner than that, because the carbides start breaking out. But, you can take a simple steel like 1095, harden it up in the mid-sixties, and go even below 10 degrees. Now you're talking really serious performance, you'll blow all your friends away in cutting competitions -- provided your knifemaker heat-treated the steel right and you are using the knife for its intended application, which in this case is controlled cutting. If 12 degrees per side satisfies you, then ZDP will work fine and there's no reason to try the 1095, which will have to be custom-made for you by a good maker. If 15 degrees per side satisfies you, you can stick with S30V at a much lower price point. You see where I'm going here: steel, heat treat, and application are all incestuously related.
In short, don't think edge geometry is necessarily independent of the other factors. The thinner you take the edge, the more critical it is you have the right steel.
Last factor: there's more to blade geometry than just the edge geometry. If you're making a big chopper, a very thin blade with a full flat grind, driven into soft woods, will penetrate deeply and stick hopelessly. On those woods, you want a blade geometry that wedges out more. The thinner blade might work better on harder woods. Again, application matters.
Joe
