1) With regard to the design above: I like the idea of multiple stop pins. But, have you considered the inclusion of an Extrema-ratio style removable stop pin for converting the knife into an ersatz-fixed blade?
Actually, I was thinking of a sliding latch which would block the liner lock from disengaging.
2) Other ways of thinking about this sort of knife; your design looks great, robust, etc. -- and I am not trying to get you to change your mind about what you want -- this is just a separate line of thought about how one might build a folding chopper. Really, these are just out of the box suggestions -- I would want to test either or both to see how well they worked -- I'm too busy to experiment with this sort of thing right now...
If it's for wilderness use -- I would care less about urban-carry legality issues, and/or speed of deployment; I would want extreme ruggedness, mechanical simplicity, ease of repair, and a design that permitted in-field reconfiguration into a fixed blade or spear should the device be damaged. Reconfiguration of this device must be possible with other multiple-purpose tools or supplies not carried on my person for this purpose alone (paracord, Kevlar fly-thread, belt buckle, etc = kosher, dedicated reconfiguration kit = not kosher).
Given that, my first thought might be to make an oversized balisong.
that is a VERY interesting concept. I'm going to have to look into that.
If you want something more complicated to make, but just as robust: a pantographic folder.
I don't know what a pantographic folder is. Great, more research!
Lucky Bob- the fellow who will likely make this knife makes knives with very tight tolerances, and could likely pull off the dual stop pin thing. Obviously, the thickness of tang stock relative to the thickness and resting position of the liner lock will take into account any potential wear, although the lock bar face will be carbidized, interfacing with S35VN at high hardness so wear probably won't enter the equation readily. A significant concern is lock failure for any reason, and adding another mechanical device to lock the lock would be preferable for a knife like this. Just gotta figure it out...
Ps. to design these things, I use a .3mm mechanical pencil and 005 permanent marker, a ruler, flexible and fixed french curves and one of them protractajators. And an eraser- probably the most important of the bunch ; )
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