Following a shock, such as from impact, a wheel pivot may fracture.
The damaged portion is removed. A conical guide is then formed to centre the drill, and the arbor is carefully drilled using a fine carbide drill.
Given the small diameter involved, this operation requires a controlled and steady approach.
A new pivot is turned from suitable steel.
The pivot is then fitted into the arbor by means of a controlled friction fit.
The fit must be correctly judged—sufficient to ensure security in service, yet without introducing stress to the arbor.
The pivot is brought to its final dimension to suit the jewel, then polished and lightly burnished to refine the surface and achieve the required hardness.
The work is thus completed.