Messages: 26267 Location: Washington, DC
Registered: November 2003
BASEL 2010 – Chanel J12 Retrograde Mysterieuse
Mon, 22 March 2010 07:45
Celebrating Chanel’s J12 10th Anniversary
In 2000, to create a black watch, perfectly black, Chanel turned to ceramic, and to the Giulio Papi team at APRP (Audemars Piguet Renaud Papi).
The first J12 tourbillon was launched in 2005. This was first in the history of watchmaking -combining a tourbillon with a ceramic watch which also had a ceramic mainplate.
Having acquired a taste for this fine watchmaking, the J12 gave itself a “manufacture” movement in 2008 (calibre 3125, developed in partnership with Audemars Piguet with an innovative ceramic oscillating weight).
Immediate response -move the crown! Why not put it on the dial, something never tried before? This immediately raised the problem of the hands -how to make them move round the dial with this crown in the way? This in turn created a further problem -a raised crown on the watch. Why not a vertical retractable crown which would be even more daring?
Just because it’s never been tried doesn’t mean it can’t be done, especially when the Chanel and Giulio Papi teams are working together. It was therefore necessary to invent, in a tourbillon movement, a minute hand capable not just of moving around the dial but also around the crown right on the dial itself.
The only way -the return journey! Move the minute hand forward until it butts up against the crown, then reverse it until it is positioned on the other side of the crown.
In this case, if the hand moves forward then goes into reverse to pick up its travel, what happens to the accuracy of the watch? How can it give the time during this retrograde interval? As the hand can no longer indicate the minutes, figures -digital display -step in in a magnifying aperture located between 5 o’clock and 6 o’clock, an ingenious idea which in no way disturbs the rate of the hour hand.
The name of this watch is beginning to take on meaning: Rétrograde for the minute hand which reverses its travel for ten minutes during which, at each revolution of the dial, the hand returns to its position under the crown -i.e. between 10 and 20 past each hour, with the minute counted in figures in the magnifying aperture at the bottom of the dial -and Mystérieuse for the mysterious workings of this dual analog and digital display. It is a highly technical and very aesthetically-pleasing watch complication.
Simple to devise but perhaps not so simple to produce! All the more so as this sequentially retrograded hand, duplicated by a digital display of minutes, is an absolute first in watchmaking history. Just like the vertical crown built into the dial, which is deactivated by pressing it flush with the crystal or activated by finger pressure to “release” and manipulate it.
To summarise, what happens every hour?
• For the first ten minutes, hours and minutes are read very traditionally in the middle of the watch.
• At the tenth minute of the hour (i.e. at 2 o’clock on the dial), the minute hand reverses its rotation and turns anti-clockwise. It is therefore moving backwards and will take ten minutes to return to its traditional position at the twentieth minute (4 o’clock on the dial). For this counter revolution of 300 (50 min. x 6/min.), it “regresses” at the rate of five minutes of dial every minute.
• During these ten minutes of retrogradation, every minute passed can be read on a disc engraved 11 to 19 in a magnifying aperture. This digital disc only moves slowly during this interval of moving backwards. It remains in neutral (no figures) during the fifty minutes of the normal rotation of the minute hand.
• After the ten minutes of moving backwards, reading the time returns to normal. • This moving backwards of the hand -a “sliding” reversal in its rate -has no adverse effect on the accuracy of the watch, unlike the traditional system of retrograde hands, which requires coiling a spring and therefore an excessive consumption of power.
• At 11 o’clock, a power reserve per hand indicates the operating time for the movement until it is next wound manually (the movement is designed to operate for ten days, once two parallel barrels are fully wound).
And what other mechanical subtleties are still hidden in J12 Rétrograde Mystérieuse ?
• The vertical crown has to be pressed to make it usable -it is normally lowered in stand-by position (functions disconnected). It then rises out of its housing.
• To set the time correctly, a vertical ceramic push-piece concealed in the bezel decoration is pressed: located at 2 o’clock, this push-piece is used to move the hands forward to set the hour and the minutes (including those between 10 and 20, with an accelerated retrogradation speed). The push-piece at 4 o’clock is pressed to disconnect this time setting function.
• To transfer to winding mode, the system is activated by pressing the vertical push-piece at 4 o’clock: the crown is turned to wind the movement. Fifty turns are needed to wind both barrels fully. This can be checked on the power reserve.
• To deactivate the vertical crown, it is pressed back into its housing where it remains blocked until next required.
• Do not miss the monolithic bridges and the ceramic mainplate, with its superb design on the back of the watch.
- Jorge Merino