CORE

In watchmaking, the core is the part of theBarrel arbor corresponding to its largest diameter, around which the spring winds. It is on the core that the hook, or notch, is located, to which the inner end of the Mainspring is attached. During the Winding — that is, the winding process —, the spring tightens and gradually coils around the core, storing the energy that will power the Movement. The shape and diameter of the core are not insignificant: they influence how the spring unwinds, the torque delivered, and the regularity of its release. A core that is too small excessively constrains the spring and impairs its efficiency, whereas an appropriate size promotes a more consistent force. A central element of the Motor organ (power source), the core thus participates, along with the spring, the drum and the cover of the Barrel, in the proper management of the watch’s energy.