Last week at the Salon International de la Haute Horlogerie (SIHH), Vacheron Constantin launched the all-new Harmony collection, featuring cushion shape cases inspired by one of the brand’s first wristwatch chronograph from 1928. The collection, produced as an homage to the brand’s 260th anniversary, consists of seven limited edition models. Today, we will cover the most exclusive of the references – the Harmony Ultra-Thin Grande Complication Chronograph. The world’s thinnest self-winding split-seconds chronograph.
The watch is presented in a 950 platinum case measuring 42 mm by 52 mm, and just 8.4 mm thick. A see-through caseback shows off the newly developed in-house caliber 3500 which is just 5.2 mm thick and features a unique gold peripheral rotor, hand engraved with a dedicated 260th anniversary pattern. The rotor design allows a full view of the movement, like you get with a hand-wound movement, without sacrificing the convenience of automatic winding.
This exquisite caliber boast 459 part (47 jewels), a 51-hour power reserve and an oscillation frequency of 3Hz. Its functions include hours, minutes, small seconds at 9 o’clock, power reserve indication and a monopusher split-seconds chronograph.
The silvered opaline dial features blue painted Arabic numerals. The hours, minutes and small seconds (at 9 o’clock) are indicated with silver hands. The split-seconds chronograph indications, consisting of two central hands for elapsed seconds, and a 60-minute counter (at 3 o’clock), are indicated with blued hands. A tachometer scale is printed on the flange in red. The power reserve indicator, located at 6 o’clock, also features a blued hand.
The technical aspects of caliber 3500, for which development began on in 2008, are quite impressive. According to Vacheron Constantin, “This caliber benefits from the numerous advanced features designed by the Manufacture’s development team, including the so-called “friction” technique for the lateral coupling clutch, which serves to reduce a potential jerk of the hand when the chronograph starts running. Another particularly notable breakthrough is the blocking of the rotor when the barrel is sufficiently wound, thereby avoiding excessive tension in the winding spring. The creation of cone-shaped wheels improves the meshing of the wheels, thus giving the wearer the impression of softer, gentler winding. Moreover, the micro-technologies used for cutting the wheels have made it possible to create extremely close-set teeth to improve the engagement of the gear trains. The creation of an ultra-thin non-spherical differential has contributed to maintaining the power-reserve indication, without influencing the movement’s thickness. Finally, the development of a “dragging” chronograph minutes indication reduces the loss in amplitude and thus improves precision.”
The Harmony Ultra-Thin Grande Complication Chronograph is being produced in a limited edition of 10 individually numbered pieces, available exclusively at Vacheron Constantin boutiques. It is paired with a blue alligator leather strap, hand-stitched and saddle finished with a platinum triple bad e folding clasp and polished half Maltese cross. This highly collectible timepiece comes with a dedicated 260th-anniversary presentation box, as well as a magnifying glass, and a dedicated brochure on the Harmony product line and a 260th-anniversary celebration letter signed by Mr. Juan-Carlos Torres, CEO of Vacheron Constantin. (Ref. 5400S/000P-B057).