The new Classique Tourbillon Extra-Plat Squelette 5395 timepiece from Breguet is equipped with a skeletonised, extra-thin tourbillon movement with a thickness of merely three millimeters. This horological masterpiece boasting a skeleton design, within an 18-karat gold caliber highlights the true craftsmanship of Breguet watchmakers.
The extra-thin 581 caliber is one of the finest self-winding tourbillon movements in the world. The skeleonized version of this movement required a series of often complex adjustments before incorporating into the watch. For instance, the rotor was placed on the periphery of the plate, saving on thickness while at the same time preserving a clear view of the mechanism.
The tourbillon has benefited from a complete redesign. The titanium carriage engages directly with the wheel train, not via the intermediary of a pinion at its base, and the silicon escapement has been given a distinct angled shape, something that considerably saves on space.
The carriage weighs no more than 0.290 grams in total – and equipped with an outstanding power reserve of 80 hours thanks to a high-energy barrel beating at four hertz – a particularly high frequency for a tourbillon.
The 581 caliber already featured in models 5377 and 5367. Here, for the first time, it has been incorporated in a fully skeletonized design. The gold plate and bridges have been hollowed out so as to display the mechanical anatomy of the movement.
The challenge was to remove as much material as possible, while preserving the technical properties of the various different components. A truly novel watchmaking complication made even more challenging by the choice of gold. Once the chosen alloy has hardened, sophisticated expertise and care are needed to achieve the final result.
The movement also boasts outstanding decoration and finishing – first of all, the hand-crafted engine-turning, or guilloche design, of the remaining plate surface. Clous de Paris hobnailing is created using a diamond-tipped guilloche tool here.
The sharp edges are painstakingly chamfered by hand, using a file until a perfectly smooth and even 45-degree bevel is created. Significant engraving work is then carried out by hand for different inscriptions as well as borders to frame the holes.
Its fluted case is topped with a domed glass-box revealing the movement. The sapphire dial features applied hour markers in blued gold. The hours chapter is created using galvanic growth and the timer is laser-engraved and filled with blue varnish. Sophisticated and minimalist, this design is rounded off with traditional blued moon-tipped hands and soldered horns in the true Breguet style.
Water-resistant to 30 meters, the Classique Tourbillon Extra-Plat Squelette 5395 is available with a gray movement in a rose gold case, or with a rose movement in a platinum case.