COUNTING

Counting is an essential operation of Regulation / Adjustment of a mechanical watch. It consists in determining, for a given Balance, the ideal active Length of the Hairspring (balance spring) allowing to obtain the Frequency of Oscillation sought — expressed in alternations or vibrations per hour (18,000, 21,600, 28,800 or 36,000 v/h depending on the calibres) — and therefore a Daily rate correct. Indeed, each Balance-Hairspring (balance spring) pair has its own active Length: a Hairspring (balance spring) that is too long makes the oscillator beat too slowly, causing the watch to run slow; too short, it beats too fast, causing the watch to run fast. Counting is carried out using a dedicated device that oscillates the Balance-Hairspring (balance spring) assembly and measures its actual Frequency while the Hairspring (balance spring) is progressively shortened, strand by strand, until the theoretical Frequency of the Calibre is reached; it also makes it possible to identify the point at which to fix the Stud (hairspring stud). This step precedes the setting to the Guide mark and the final matching of the Hairspring (balance spring) to its Balance. A high-precision operation, Counting directly determines the chronometric quality of the timepiece; it falls within the expertise of the regulator, a specialist in the regulating organ and its fine adjustment.