A workpiece system with a reciprocating motion which includes a motor assembly for producing an output drive signal with a periodic force pulse. The drive signal is coupled to a driven member assembly through a magnetic arrangement, wherein the driven member assembly has a workpiece mounted thereon with a return spring assembly. The driven member assembly has a resonant mechanical frequency. As the RPM of the motor increases from zero following startup, the drive signal frequency increases to the point very near resonance, where the energy from the drive signal is transferred into the reciprocating motion of the driven assembly, producing an effective amplitude of workpiece motion.