The pylons rise upwards at an angle (leaning towards each other for triangle stability), but the hinge pivot axis needs to be horizontal. Embedding a straight piece of steel into the cap put each end of the hinge too close to the edge of the cap for good strength. I welded up an offset hinge that would not weaken the cap too much.
The hinge material will stay vertical and the top cap will pivot on a large pin. I will radius the bottom of that top cap to allow it to pivot cleanly.
