ABB IRB 120 Robot Model

Links of the robot are connected by magnets and rotate freely. Joint 6 is removed to give space for a magnet for mounting end-effector.

Model derived from stl found in a ROS repo and edited with meshmixer and meshlab to add slots for magnets and simplified for printability.

Magnets spec
15x3, 12x3, 10x3, 8x3, 8x3 (mm) disk magnets, axially magnetized.

I bought mine here