Locates $T3vibrating$T1 point (point at which length of spring is such as to cause attached balance wheel to oscillate at specified rate) on clock and watch hairsprings and cuts hairspring at specified point to synchronize oscillation of movements, utilizing one or both of following methods: (1) Fastens free end of spring of hairspring assembly in fixture of electronic vibrating device, and adjusts bed of device until it touches pivot of vertically oscillating balance wheel, as indicated on cathode-ray tube.
Observes second cathode-ray tube to determine excess length of spring as vertical swings are translated into corresponding horizontal oscillations. Winds excess length of spring into holding fixture of device and readjusts bed until cathode-ray tube readings are within acceptable limits. Starts shears to cut excess spring at specified distance from vibrating point for attachment to stud. (2) Inserts end of spring into holding tweezers of master balance wheel assembly, and adjusts tweezers until pivots and arms of test and master balances are aligned. Releases lever that gives starting impulse to both balances simultaneously, and observes operation to determine if balances are synchronized. Resets holding point of vibrator tweezers and repeats operation until balances are synchronized. Cuts off spring at specified distance from vibrating point for attachment to stud, using cutting pliers.
