in place of a pneumatic cylinder and piston assembly in some embodiments that include the cutter actuator 500 shown in fig5 when an electric voltage is applied to a solenoid coil within the solenoid body 716 a magnetic field is generated which pushes a magnetized armature rod 718 outward from the solenoid body 716 and toward the clamshell cutter device 202 when the magnetic field is switched off a return spring located inside of the solenoid body returns the armature rod 718 to its rest position in similar embodiments the return spring is located elsewhere in the mechanism and not inside of the pneumatic cylinder fig8 a is a side view illustration of a preferred embodiment of a cutter actuator 800 including a pneumatic cylinder and piston assembly 802 a rotatable drive component 804 and an actuator arm 806 in this embodiment air forced into the pneumatic cylinder 802 pushes a piston 808 which forces the rotatable drive component 804 to pivot about a fulcrum 810 thereby magnifying the range of motion of the piston 808 and pushing the actuator arm 806 the actuator arm 806 pushes half of the clamshell cutter device 202 into the closed position a similar arrangement of elements not shown located on the other side of the cutter head 100 simultaneously closes the other half of the clamshell cutter device 202 when the air pressure is released a from the pneumatic cylinder 802 a spring 812 returns the rotatable drive component 804 to its original rest position thereby retracting the actuator arm 806 and opening the clamshell cutter device 202 in this embodiment the actuator arm 806 and.