Da Vinci Perpetual Calendar ChronographThe line premieres a new manufacture calibre that supports the unprecedented presentation of the chronograph’s double counter and the moon’s phase on a single subdial.
- Material: 18 k red gold
- Movement: Automatic, Caliber 89630
- Diameter: 43 mm
- Special features: Perpetual calendar with four-digit year indicator, perpetual moon-phase display, flyback chronograph
- Wempe reference: IW310059
Precision can’t be more beautiful
If you’re familiar with the Da Vinci chronograph from 1985, it won’t take you much effort to get used to this 43-mm newcomer, which premieres in 2017. The perpetual calendar puts the date, day of the week, and month at the same locations that they occupy on their predecessor: the four-digit year is in its habitual place at the 7:30 position and the moon-phase display has stayed below the 12 o’clock position. Close scrutiny is needed now, because the semicircular window has been replaced by a round opening in the dial. This moon-phase display runs much more accurately than the previous version: rather than erring by one full day after 122.6 years, it deviates by 24 hours only after 577.5 years have elapsed. Imagine how much water will have flowed down the Rhine before the year 2594 arrives! The redesign is due to manufacture Caliber 89630 and its technical elements: after the chronograph has been switched on, the 60-minute and 12-hour counters make their revolutions perceptibly as an ensemble in the top half of the dial. This is an element that had to be taken into account when the moon phase display was designed. The chronograph boasts traditional features such as a column wheel, rocking pinion coupling, and a flyback function. A chronograph center wheel with 240 specially shaped teeth nearly eliminates the notorious judder accompanying the start of the chronograph’s second hand. The high efficiency of the chronograph mechanism can be deduced from the fact that the 68-hour power reserve is scarcely diminished when the chronograph runs continually. Its Glucydur balance has four regulating screws on its rim, while its freely breathing flat Anachron hairspring completes 28,800
beats per hour. Instead of IWC’s usual Pellaton winding, this movement has an innovative system that allows winding in both directions thanks to four pawls that transform the kinetic energy of the shockproof, heavy metal rotor into potential energy. The oscillating weight is visible through a transparent pane on the back of the red gold case, which is water- resistant to three bar.