Blancpain Villeret Chronographe Monopoussoir (Single Push-Piece, Ref. 6185-1546-55) with Calibre 1185 – The World’s Thinnest Automatic Chronograph (1987)

The ability to measure precisely intervals of time, by starting and later stopping a count, has long been one of the core complications of the watchmaking art. This, of course, is the function of a chronograph, and chronographs have cemented their place as a staple of Blancpain’s collection. Variants have included the originally introduced traditional two-button chronograph and a single-button, or monopoussoir version.

Blancpain has also earned its reputation as a world leader in chronographs by developing additional complications which elaborate the chronograph function – the split-seconds chronograph and Blancpain’s famous Flyback – and creating combinations of complications which include a chronograph – examples being a perpetual calendar chronograph and a tourbillon chronograph. All of these chronographs have been developed using Blancpain’s pioneering Calibre 1185 movement, which debuted in 1987.

Villeret Chronographe Monopoussoir (Single Push-Piece) (Ref. 6185-1546-55)

From the day it entered upon the watchmaking stage and still today, the 1185 has been revolutionary and unmatched. It is the world’s thinnest automatic chronograph movement. Not only has its 5.5 mm thinness never been equalled by any other automatic chronograph movement, but, when it debuted, it was thinner than its manual winding Haute Horlogerie competition, even though it was an automatic movement. Blancpain set this world record for thinness without straying in the slightest from the most demanding chronograph design criteria.

Traditional top of the range chronograph movements are built using a component known as a “column wheel” to control the starting, stopping and resetting of the chronograph. Only with a column-wheel design can one be sure that the pushing of the buttons will be both precise and silky smooth. Although to save costs most chronographs on the market today have dispensed with column wheels, Blancpain respected tradition and made the column wheel a centrepiece of its design, even as it was breaking the world record for thinness.

Beyond its revolutionary thinness, Calibre 1185 was a towering achievement in other respects, too. Commonly, even the most expensive chronograph movements have been bedevilled with some harshness in operation. Unavoidably, as gears are suddenly forced to mesh when chronographs are started, there may be a degree of jerkiness perceptible in the hands. Not only that, but even with the finest of chronographs, it is recommended that the chronograph not be left running.

This is because of the fragility of chronograph gears and because the timekeeping of the movement is compromised with the extra-power drain of the running chronograph mechanism. Blancpain solved these traditional chronograph problems with the development of an innovative vertical clutch in Calibre 1185. Instead of gears being forced to mesh suddenly, the starting of the chronograph proceeds with a smooth engagement of two plates. As a result, there is never a sudden or harsh jump of the chronograph seconds-hand. Moreover, this innovative approach allows unlimited running of the chronograph mechanism with only minimal effects on the movement’s timekeeping.

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.