Can we go a step further on this subject?
I took a few minutes to draw the instructions as you gave them then added hinges. Please see attached 1 and 2. (1 looks OK, 2 looks like it has problems)
Since the pivot point moves depending on the location of the hinge how do you adjust the cuts to be able to get a correct rule joint, that being; fitting when up, hiding the “space” when down and not a 1/8” gap in the horizontal direction?
I have done “one” of these joints before (a number of years ago) (on a shaper, I have a matched set of cutters) but followed the directions that came with the hinges and never did understand what I did.
Maybe a full-fledged tip one day soon would help me out?????