The Overseas Tourbillon Skeleton comes in two versions, one in 18K 5N pink gold and the other in Grade 5 titanium. The titanium model is the first by the Maison to be entirely made of this same metal – from crown to bezel and from bracelet to case. The self-winding Manufacture Calibre 2160 powering these timepieces has been entirely skeletonised in a contemporary spirit with a degree of attention to detail stemming from an authentic aesthetic quest celebrated by Vacheron Constantin.
The skeletonisation work carried out on self-winding Calibre 2160 has enabled not only a 20% reduction in the movement’s weight but also a complete rethink of its architecture. Its curvature is thus very slender, at barely 5.65 mm thick – a real technical feat considering the requirements linked to the integration of a tourbillon carriage. This thinness is notably due to the choice of a peripheral gold oscillating weight, which also enables a completely clear view of the rear of the movement. The work done on the baseplate and the four bridges can be clearly admired, with the NAC (N-acetylcysteine) surface treatment applied by electrolysis conferring an anthracite grey tint. This contemporary touch given to the movement blends perfectly with the classic haute horlogerie finishes in the form of hand-drawn flanks and hand-chamfering with polished bevels to accentuate the light playing across the components. The mainplate and bridges are also delicately decorated to create a finish of very fine, perfectly horizontal grooves. Such concern for details is a credo which holds that even the smallest part deserves the same meticulous attention as those that are perfectly visible.
The same NAC surface treatment can be found on the barrel, of which the drum and cover have been entirely openworked, creating a compass rose shape on the dial side – another original feature of Calibre 2160 SQ. To complete the openworking of this 186-component movement, the wheels have also been made lighter, while the tourbillon is held by a rounded-off upper bridge. The tourbillon regulator rotating once per minute operates at a rate of 18,000 vibrations per hour (2.5 Hz) and serves as a small seconds indicator by means of one of the four screws used to secure the carriage and which is grey on the pink gold version and flame-blued on the titanium version.
For this new calibre, Vacheron Constantin’s watchmakers have also redesigned the regulating organ housed in the tourbillon carriage coupled with the escapement. A new balance-spring was designed in-house, equipped with a Breguet overcoil (terminal curve). By folding the outer spring coil towards the centre, outside its horizontal plane, this arrangement forces a flat development of the spring, thus ensuring enhanced isochronism.
The hour-markers secured to this crystal are in rhodium-plated 18K 5N pink gold or 18K white gold, depending on the model. The same noble metals are used for the hands which, like the hour-markers, are coated with Super-LumiNova® ensuring perfect night-time visibility. The dial ring is available in black lacquered 18K 5N pink gold or in blue PVD-treated 18K white gold.
Developed and manufactured by Vacheron Constantin
Mechanical, self-winding, peripheral rotor
31 mm (13½’’’) diameter, 5.65 mm thick
Approximately 80 hours of power reserve
2.5 Hz (18,000 vibrations per hour)
Hallmark of Geneva certified timepiece
Hours, minutes, small seconds on tourbillon carriage (coloured screw)
18K 5N pink gold / Grade 5 Titanium
42.5 mm diameter, 10.39 mm thick
Soft iron casing ring ensuring anti-magnetic protection
Transparent sapphire crystal caseback
Water-resistant tested at a pressure of 5 bar (approx. 50 metres)
18K 5N pink gold / 18K white gold hour-markers and hours & minutes hands highlighted with Super-LumiNova®
18K 5N pink gold bracelet / Grade 5 Titanium (half Maltese cross-shaped polished and satin-brushed links), secured by a 18K 5N pink gold / Grade 5 Titanium triple-blade folding clasp with push-pieces and comfort-adjustment system
Black / blue calfskin leather with white stitches
Black / blue rubber