A professional who tends semiautomatic turning machine to cut recess in watch balance wheel. Respnsibilities include:

• Fits center hole of balance wheel over pin protruding from face of quill (removable headstock), using tweezers.
• Fits holding ring over wheel and depresses pedal to clamp ring in place.
• Depresses pedal to start machine.
• Observes machine operation to detect malfunction.
• Lifts recessed wheel from pin, using tweezers, when machine automatically stops at end of cycle.
• Verifies contour of recess, using go-not-go gauge, depth of recess, using upright gauge, and quality of cut, using jeweler's loupe.