Girard-Perregaux presents the first ever skeleton version of its Neo Tourbillon with Three Bridges.
The Neo Tourbillon with Three Bridges Skeleton is a natural extension of several Girard-Perregaux fundamentals. The first is the 1884 patent for a tourbillon with three bridges visible on the dial side, the principle underlying the “With Three Gold Bridges” architecture and unique signature of Girard-Perregaux fine watchmaking.
The second is the skeleton working on this type of movement that Girard-Perregaux has been practicing since 1998. The third stage was the birth in 2014 of the Neo Tourbillon with Three Bridges. The latter were not straight, flat or in gold, but instead arched, taut, rounded, open-worked and black.
The model is presented in a 45 mm-diameter titanium case measuring 15.85 mm high. With its ample curves and large glazed areas, this shell resembles a panoramic observation platform looking out onto a horological monument. The satin-brushed bombed case band is distinguished by the total absence of any bezel. Its polished lugs are perched high on the case so as to create a strong and early inflection. It is this curve that ensures the Neo Tourbillon with Three Bridges Skeleton sits so snugly on any wrist, however small.
Dominated by sapphire rather than titanium, the case is built so as to maximise the view of the movement, itself based on the principle of transparency. The dial-side crystal is of the glass box type, steeply cambered and convex. It rises vertically from the case, before changing angle to cover the heart of the watch, like a protective dome. The caseback crystal is also convex, meaning that, when viewed from the side, the Neo Tourbillon with Three Bridges Skeleton is a band of grey metal with a matt appearance achieved by satin brushing, framed by two sapphire protrusions.
These scratchproof, complex and chemically pure crystals thus reveal the structure of the GP 9400-0011 calibre, a profoundly revisited version of Calibre 9400. This restructuring mainly consists of skeleton working that basically involves eliminating the baseplate. Almost as if the ground had vanished beneath its feet, the movement finds itself suspended between two layers of air. Certain indispensable anchor points remain, but the opaque and solid supporting structure has disappeared. A closer look shows the screws holding the openworked, polished and bevelled bridges, driven far into the structure of the calibre.
Contrary to other skeleton models made by Girard-Perregaux, the Neo Tourbillon with Three Bridges Skeleton has not sought to create a graphic shape by open-working, but instead to ‘erase’ the material so as to enable the bridges to express themselves to the full. The movement base-plate, which is solid on Calibre 9400, is replaced here by two bridges. The latter are exactly identical to those on the dial side: a first in a structure based on visible bridges. These two bridges are the counterparts of the gear-train bridge (in the centre) and the tourbillon bridge (at 6 o’clock). Their subtly arched shape slightly increases the overall movement thickness.
The calibre of the Neo Tourbillon with Three Bridges Skeleton is 9.54 mm thick, while the titanium caseband is the same size as on the previously released model. Physical lightness is ensured by the low weight of sapphire and titanium and their limited presence, while visual lightness is created by skeleton-working. The bridges contribute to the overall transparency of calibre. They are made of titanium, sandblasted and then blackened by a PVD process. Their 3D shape is so complex, composed of interior angles, arches, extensions and overhangs, that their machining is a watchmaking feat in itself. The result is a free, sensual, taut and powerful shape.
Coursing between these bridges are the two life-flows of watchmaking: the exchange between energy and information, between the force stored in the barrel and the regulating effect of the tourbillon. The former is wound by a micro-rotor, which is placed concentrically with the barrel – a unique position for this organ. The high inertia of this hefty white gold micro-rotor ensures a minimum 60-hour power reserve. At the other end of the kinematic chain sits the Girard-Perregaux tourbillon.
This 80-part component is made from titanium so as to safeguard operational autonomy and reduce friction. It spins on its axis once a minute, driven by a large-diameter balance wheel coupled with a hairspring featuring a Philllips terminal coil and a Swiss lever escapement. The entire fully assembled carriage weighs just 0.25 grams.
Model: Neo Tourbillon with Three Bridges Skeleton
Case and dial
Diameter: 45,00 mm
Thickness: 15,85 mm
Glass: sapphire anti-reflective treatment “box”, steeply cambered, convex
Case-back: sapphire crystal “box”
Dial: no dial, no ring
Hands: “Dauphine” type, brushed white gold
Water resistance: 30 metres (3 ATM)
Reference: GP 09400-0011, skeletonised, mechanical with automatic winding
Winding: unidirectional via an 18K white gold micro-rotor, coaxial with the barrel
Diameter: 36,00 mm (16’’’)
Thickness: 9,54 mm
Frequency: 21,600 vph – (3 Hz)
Number of components: 260
Power reserve: min. 60 hours
Tourbillon, hours, minutes, small seconds on the tourbillon
Tourbillon cage in Titanium, 80 components weighting 0,25 grams
Bridges: 5 skeletonised, bevelled, sandblasted, black PVD-treated bridges
Material: Hand-stitched black alligator
Buckle: Titanium triple folding clasp