The Running Equation of Time function is rarely executed in watchmaking. Here it is combined with a perpetual calendar, moonphases indication and entirely hand engraved automatic calibre.
Blancpain Villeret Équation du Temps Marchante Quantieme Perpetuel 6638-3431-55B
Functions; running equation of time, moonphases, perpetual calendar and 24 hour indication.
Material Platinum Case thickness 11.50mm Case diameter 42.00mm Water resistance 3.00 bar (approximately 30 meters) Between shoulders 23.00mm Sapphire crystals front and back with anti-reflective coating
The equation of time shows the difference in the hour of a day between “solar time” and “civil time”. Civil time assumes that a day has exactly 24 hours and is constant during the year. Solar time is calculated based upon the real length of a day (the number of hours that pass between the time when the sun is in a given position in the sky and when it is in that same position the following day, which alters during the course of the year).
Recto-verso of the case back.
The case back removed showing the full five correctors, movement and movement ring.
Winding automatic Calibre thickness 5.25mm Calibre diameter 26.80mm Power reserve 72 hours Jewels 39 Components 397 Frequency 4 Hz / 28’800 A/h
Rotor removed showing the fully engraved bridges.
Base movement in various stages of dismantling.
Balance assembly with cock
The Nickel Phosphore treatment on the sliding pinion is a new technique which increases its hardness and durability. The setting mechanism traditionally receives more wear than most other parts of the calibre due to the manipulation it experiences directly from the users adjustment of the watch.
Partial explosion of the 3863 movement, excluding module.
The perpetual calendar and equation module, shown once the dial is removed.
Underside of the module.
A selection of the principle wheels and cams from the module.
A congruently thought through and executed complicated timepiece, containing the applications of a QP with the equation of time and the aesthetic elements reinforcing those functions in an artisanal engraved execution, stylistcally following the theme of the watch.
Article by The Naked Watchmaker
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