A WONDERFUL HANDS COMPLICATION NAMED: PANTOGRAPH !
The star of the new Oval Collection is without doubt the Pantograph complication, whose hands perform a subtle dance to the passage of time. The hands are based on the pantograph - the instrument from which they take their name - and use the same principle of multiplying a length by a given factor to obtain movement on a larger or smaller scale.
In concrete mechanical terms, a cam at the centre of the movement determines a certain length which is then replicated X number of times across the entire hand. In other words, the measurement of this central cam provides the information required to move the hand and adjust it as it pursues its course around the dial.
This trajectory and its elongation have been meticulously calculated so that the hands trace a perfect, harmonious ellipse. A computerised simulation also ensures that the minute hand is never retracted as far as the hour hand, which means, for example, that 12:15 cannot be confused with 3 o'clock.
Confounding expectations, the main challenge posed by this extraordinary piece was not the horological complication itself, but rather the cutting and, in particular, assembly of the telescopic hands. Composed of fine segments of aluminium which slide over each other, these hands must operate perfectly irrespective of the level at which they are deployed. The crucial adjustment steps are dependent on the watchmaker's dexterity, which no machine can replicate. The riveting of the different aluminium segments is done by sound and sight. As the rivet is struck, the skill is in identifying the moment at which the rivet is deformed, as indicated by a characteristic "tink" which occurs when the material is altered, precisely signalling the end of the operation. Following this, the aluminium segments must slide completely freely over each other without the slightest play. The watchmakers must therefore achieve an extremely precise balance at each intersection in the structure to ensure that the piece functions correctly as a whole.
The basic movement used in the Ovale Pantographe is the oldest created by Parmigiani Fleurier: the calibre PF110 was designed for the Hebdomadaire line. With the addition of the retractable hand module, the new movement, known as the PF111, combines a pantograph on a manual movement with a power reserve of 8 days.