This is a simple 2 part pivot hinge with a snap in pin. The center pin is the weak point in the design, but it is strong enough to snap into place.

This was developed as a model for a knee brace hinge for a sports medicine class. It's not full size, nor would it be strong enough to use in an actual knee brace - but instead it is an educational tool.

I printed it on an Aluminatus using PLA. .4mm nozzle, 75% infill and .3mm layer height. I didn't have any ABS on hand to work with.