Folder design with best lateral/prying strength

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SAK or Scout/"Demo" knife screwdriver blade.

FYI: A knife is designed and intended to cut things. They are not designed or intended to be used as a prybar or screwdriver.

If you need to pry, get a pocket size or larger pry bar.

"The right tool for the job" is easier, faster, safer, and probably cheaper/less expensive in both short term and long term.
 
We had a guy here about two years ago that was touting his, “Folding knife with Fixed Blade Capabilities” Never heard back from him. People cut with knives & pry with a prybar, open paint cans with a large flat screw driver.. A tool designed to do several things usually does a poor job at most or all of them..
 
Let’s think objectively here, a better lock design resisting lateral force does not have to affect blade geometry/cutting performance

Some of the design features already mentioned have no effect on blade geometry...you could stick whatever blade shape on it you want
 
Problem solved.
https://kershaw.kaiusaltd.com/knives/knife/barge

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You know you do it. And you know you shouldn’t. You should never use the blade of your knife—especially the blade of your folding knife—as a pry bar.

However, if you’re pry-prone anyway, we now have the right knife for you. The Barge features an integral pry bar that extends from the backspacer of the knife. Now there’s no need to even think about wrenching on something with your blade. Finally, you’ve got the right tool for the job—an actual pry bar built into the back of the knife.
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Next problem?
 
Scrolling down the page, thinking "wait, there's the Kershaw Barge."

Oh. Uh. Nevermind.
 
The challenge is how to make a *folding blade* resist lateral and vertical force.

Instead there’s a bunch of responses on how you shouldn’t pry with a folder. That’s not the question here. It does not matter whether you think a folder should be used for prying, a heavy use knife will be subject to lateral forces
 
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Thereisnocowlevel said:
The challenge is how to make a *folding blade* resist lateral and vertical force.

Instead there’s a bunch of responses on how you shouldn’t pry with a folder. That’s not the question here.
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Take one folder ........ any folder , TIG weld perimeter where it fold and that is that :D
Seriously , it can be done easy . I don t see any problem , just overbuild everything .
 
When I think outside the box, I think I’m more concerned with breaking, chipping or bending a blade more so than the lock design. I think most steels used for knives aren’t designed for lateral strength, so it’s a moot point to discuss. Just because you can, doesn’t mean you should. Same goes for fixed blades. You definitely can dish out more abuse on a fixed blade, but that doesn’t mean you should. To repeat what’s already been said, the right tool for the right job. I know for a fact, if you use a screwdriver for a chisel, you stand the chance of breaking it. If you use a screwdriver for a pry bar, you stand a chance of breaking it. I’ve done it in both cases, and you’ll feel dumb if it’s the only one you have at the time.
Using your knife to remove a staple from a stack of papers isn’t a big deal, using your knife to remove a commercial/box staple is dumb.
 
Thereisnocowlevel said:
I don’t understand why in the knife community there’s such a push back on lateral strength.
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This is the Amphicar. It was designed to be a car that also functioned as a boat. Not something necessary of course, but someone thought it was a good idea. It's a crappy car... and a crappy boat.

Designing a knife to also be a good pry tool is the same sort of bad idea. It's a folding knife. It should be good at being a folding knife first and foremost. Any criteria that would increase its efficacy as a pry tool would decrease its cutting performance.

If you need a pry tool then carry a pry tool. I use the flathead on a SAK. You're also free to use your knife as a pry tool if you like, but suggesting that it should be built for the task or that the manufacturer should warranty it against damage from prying is like suggesting the 2020 Corvette should do 70 knots on calm water.
 
How would a change lock design to better resist lateral force decrease the blades cutting performance?

Most of the design features we discussed so far you could add that to any blade shape you want
 
Some folders do fine prying. I've got one that's done a ton of it and still works like new.
 
Aaron Frederick makes the VBSS Breach which is designed for it. Some SEAL teams use them for breaching doors.

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Thereisnocowlevel said:
How would a change lock design to better resist lateral force decrease the blades cutting performance?

Most of the design features we discussed so far you could add that to any blade shape you want
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I haven't seen you really discuss any features that are specifically related to lateral force. You keep mentioning locks as if that's the common point of failure while prying. It isn't. The blade breaks or the handle breaks.

Fixing that means you either make the steel "tougher" which always comes at the cost of edge retention or it means simply adding steel, making the blade thicker and harder to push/pull through a material.

If you want the innovation then why not make it yourself? Most knife makers and designers, with all due respect, aren't super geniuses. They have no special, rare ability or qualification. Instead of badgering folks into agreement that the innovation is necessary (or possible) why not just get out there and do it?

The reason it hasn't been done isn't some manufacturing conspiracy, it's just common sense. Blades make bad pry tools and pry tools make bad blades.
 
Thereisnocowlevel said:
The challenge is how to make a *folding blade* resist lateral and vertical force.

Instead there’s a bunch of responses on how you shouldn’t pry with a folder. That’s not the question here. It does not matter whether you think a folder should be used for prying, a heavy use knife will be subject to lateral forces
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And yet I have carried and used knives for 60 years and have not had a problem due to "lateral stresses".
 
knarfeng said:
And yet I have carried and used knives for 60 years and have not had a problem due to "lateral stresses".
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But what if you did? Now give me several empirical fixes for this hypothetical failure.
 
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