i used the dallara as a model. imagine a vertical line down the center of the pivot. when the ball remains behind this line with the knife open, it blocks the tang and prevents the knife from closing. when the ball is there in the closed position, it lands in the choil of the blade, keeping it closed. i'm not quite sure what you mean by "angled" but maybe you mean something like the poliwog? if so, yes. there's a lot of blade outside of the grips in the closed position on the dallara too because of the massive spyder hole. i think the 110 style nail nick or a thumb stud/ridge would prevent that. i left that detail off having not made up my mind. ball lock action is so smooth you barely need anything for your thumb to grab.

wouldn't mind just making it a massive framelock either, with the guard acting like a flipper.