SIHH 2014: Piaget Altiplano 900P – Updated with Live Photos Written byJoe ThompsonJanuary 22, 2014 For more than half a century Switzerland’s Piaget has specialized in manufacturing ultra-thin mechanical watches and watch movements. Now it has produced what it says is “the thinnest mechanical watch ever.” The new Piaget Altiplano 900P has a total case thickness of 3.65 mm, 9.9 percent less than the thinnest mechanical watch currently on the market, the 4.05-mm-thin Jaeger-LeCoultre Master Ultra-Thin Jubilee. The Altiplano 900P has an 18k-gold case (white or rose) and will sell for around $20,000 when the watch reaches stores in 2014. The watch was formally unveiled at the SIHH exhibition in Geneva this week; Piaget presented press previews of the watch in December. Piaget accomplished its world-first by employing an ingenious, radical engineering solution. It “merged” the caliber with the case, using the caseback to serve as the mainplate. The result is that the watch does not have an independent movement that can be removed from the case. The mainplate is machined out of the caseback. This procedure gives the watch its extraordinary thinness. It is the same principle behind the construction of the famous ultra-thin Concord Delirium watch, which set a world record for thinness in 1979. The Delirium was a quartz watch whose total thickness was 1.79 mm. A later version, Delirium IV, was thinner than a millimeter; the watch was an astounding 0.98 mm thick. The same caseback-as-mainplate principle is used in quartz Swatch watches. Piaget is the first to apply the principle to mechanical watches. The watch’s unorthodox internal architecture and the need for maximum thinness required Piaget to make technical changes that give the watch its unusual design. Using the caseback as a mainplate forced Piaget to reverse the traditional movement construction and make the bridges part of the watch’s dial. Hence, the entire wheel train is visible on the dial. Among the technical innovations is a barrel suspended from a single bridge on the dial side as opposed to the traditional spot fixed to the mainplate. The world’s thinnest mechanical watch: Piaget’s Altiplano 900P The watch took three years to make, Piaget says, and required closer-than-usual coordination between a team of watchmakers, case constructors and designers. The entire watch was designed and produced in house at Piaget’s two Swiss plants — the movement facility in La Côte aux Fées in the Swiss Jura Mountains and the factory at Plan-les-Ouates outside Geneva, where it produces cases. The Piaget team sought to save space wherever it could in the 145-part watch. Some wheels measure 0.12 mm thin, for example, compared to 0.20 mm in a classic movement. To save an additional few millimeters, the entire mechanism and the hand-fitting system are contained within the thickness of the balance wheel itself (and led to the off-center placement of the hours and minutes display). The entire watch is just 3.65 mm thick. Piaget says it has solved the problem that plagues extremely thin watches: their tendency to bend slightly under pressure. The Delirium watches, for example, were so thin that merely strapping them on the wrist bent the rectangular case slightly, causing the crystal to press against the hands, stopping the movement. To avoid such problems, Piaget’s construction places the hands at a level below the bridges that surround the hour and minute display, creating space between the cannon pinion and the crystal. Should the crystal bend from the effects of pressure, it presses on the wheel-train bridge, not the hands, with no impact on the timing mechanism. A Piaget patent for this solution is pending. The 900P gets its name from Calibre 9P, Piaget’s first ultra-thin hand-wound movement, which was introduced in 1957. Many more ultra-thin movements followed. Of the 35 total movements Piaget has developed and produced in house, 23 are ultra-thin. Twelve of the 23 ultra-thin movements have set records and are currently in production. Below, find some live shots of the Piaget Altiplano 900P, taken by WatchTime’s Mike Disher during SIHH 2014.