INDENTING

The indenting is the operation, and its result, which consists in slightly pinching a pipe — most often that of the cannon pinion — in order to create a bulge inside its tube. This local narrowing produces a calibrated friction between the pipe and the axis on which it is mounted, here the pivot shaft of the centre wheel. This gentle friction is essential to the operation of the motion work: it allows the cannon pinion to drive the minute hand while allowing, when setting the time, the necessary slippage to turn the hands without forcing the train (wheel train). Indenting that is too weak causes slipping and delay of the hands; too strong, it stiffens the time-setting and overloads the Movement. Finely adjusted, it ensures the right balance between drive and slippage. Indenting illustrates the mastery of controlled friction, essential to the functions of Display and Regulation / Adjustment of the watch.