Mount for servo based magnetic uncoupler

This is a mount for an SG90 style servo to drive uncoupling magnets for model railway uncouplers. It was designed for use in P4 with Alex Jackson couplings but could work in OO or EM with other magnetic couplings. The mount is sleeved with a short length of plastruct tube which has a smooth bore and allows the plunger part to slide easily. A small 6mm diameter rare-earth magnet is attached to the top of the plunger.