OP is still looking in so here are my final thoughts:
FET, IRF520, 100V, 8A, .3 ohm or similar; Slot interrupter, ON1102, CNZ1102, IR LED 50 mA , - transistor sensor 20 mA @ 30V. or similar.
I would put a 2 ohm resistor in series with motor to limit peak current @ 10W , assuming intermittent use.
FET, IRF520, 100V, 8A, .3 ohm or similar; Slot interrupter, ON1102, CNZ1102, IR LED 50 mA , - transistor sensor 20 mA @ 30V. or similar.
I would put a 2 ohm resistor in series with motor to limit peak current @ 10W , assuming intermittent use.