Making a minute hand collet for a French Strike clock using a clock key. Firstly select a clock key which will fit over the cannon pinion and cut off the complete shank.
The component parts to be machined are as follows. 1. The diameter must allow the hour wheel (A) freedom 2. The length must allow the pinhole (B) in the centre wheel (C) to be exposed just enough after the hand washer (D) and the cannon pinion (E) are fully depressed allowing the pin to be fitted and give sufficient tension for the hands.
3. Thick enough to support the hand but allow the hour wheel some end play. 4. Enough rivet height to stand proud of the hand.
This diameter must be a firm fit in the hand to allow adjustment of the hand on the collet before final riveting. Adjust minute hand so make sure the clock strikes exactly on the hour and complete the riveting.
