The Reason

This is an unusual execution of a perpetual calendar, unique in its intricasies and historically never executed in this way before.  

Made by MB&F and independent watchmaker Stephen McDonnell.  With 581-components. Below are three watches of the same model. A fully assembled and cased QP (QP = French, Quantium Perpetual- English, perpetual calendar). Secondly, components from a kit for a movement to be assembled with a different colour mainplate. Lastly a semi complete movement, advanced, shown with and with out subsidiary dials.

Legacy Machine Perpetual 

One of the characteristics with this Perpetual Calendar which differentiates it from other conventional examples which are finished as this one, predominantly by hand and made in small numbers, is the adjustment required after assembly. Normally with QP's there is a considerable amount of time consumed to assure the mechanism functions correctly, here the watch is assembled and works with little to no adjustment.

A perpetual calendar automatically adjusts to the variable length of each month and leap year.

Please click on the images below to enlarge and to read additional information.

The movement sitting in a brass movement ring and placed on to a nylon support for manipulation, allowing the movement to be turned over to allow access to both sides during assembly.

QP's tend to be made as slim as possible to reduce the thickness of the final watch. Here the Qp is fully visible and some of the components are made on multiple layers emphasizing the horological nature of the construction producing a substantial piece of 3 dimensional horology.

Side profile of movement outside of the case illustrating the thickness of the wheels and components which the QP comprises of. 

The assembly to the right of the image with the blued hand, controls the length of each month

The assembly to the right of the image with the blued hand, controls the length of each month

Balance bridge and balance wheel.

Balance bridge and balance wheel.

Diverse angles of the movement, recto-verso.

Diverse images

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