Vacheron Constantin presents the Les Cabinotiers minute repeater tourbillon sky chart Leo constellation Jewellery watch, a single-piece edition adding an artistic dimension to the technical prowess of its Calibre 2755 TMRCC. The Manufacture’s craftsmen, gemsetters and guilloché specialists have adorned an extraordinarily complex timepiece with a creative and original evocation of the Leo constellation.
This new model, presented at Watches & Wonders 2021, is part of the theme of the Maison for 2021: entitled Classic with a Twist, it highlights Vacheron Constantin’s creative energy, guided by an identity that celebrates a heritage and dares to deliver the unexpected.
Early astronomers’ observations led them to recognise animal forms in the configuration of the constellations, including that of a lion. Vacheron Constantin’s artisan drew inspiration from this to highlight the astronomical complication of this single-piece edition Les Cabinotiers watch.
Hand-guilloché and set with diamonds forming the Leo constellation, the noble creature stands majestically on the dial, framed by a case set with baguette-cut sapphires. This artistic and artisanal interpretation adds an artistic dimension to the technical prowess of Calibre 2755 TMRCC, which combines a tourbillon regulating device, a minute repeater in the grand tradition of the Maison’s striking watches, as well as a rotating sky chart.
The watch flaunts its elegance in an 18K white gold case measuring 45 mm in diameter and barely 15.1 mm thick, fitted with a dark blue alligator strap secured by a gemset gold buckle.
Already accentuated by the presence of a tourbillon, the complexity of the Les Cabinotiers minute repeater tourbillon sky chart Leo constellation Jewellery watch is further heightened by the mobile representation of the sky chart on the back of the watch. This vision of the constellations inspired the motif adorning the guilloche opaline dark blue dial, itself enhanced by the sparkling case adorned with 100 baguette-cut sapphires bezel-set on the lugs, crown and bezel.
The Leo constellation is staged to great effect on the dial. A masterpiece of hand guilloché craftsmanship created in the Vacheron Constantin workshops, the feline’s silhouette is composed of a multitude of triangles bearing their own motifs.
Since the rose engines operated by skilled artisans with an artist’s touch are designed to engrave decorative elements that are generally circular and geometric, it is easy to grasp the difficulties implied by depicting a lion in the form of a combination of polygons whose linear engravings provide striking depth effects. The stars composing the constellation are represented by brilliant-cut diamonds adorning the great cat’s tawny coat.
The 413-component Calibre 2755 TMRCC of the Les Cabinotiers minute repeater tourbillon sky chart Leo constellation Jewellery watch combines three horological complications in the technical, astronomical and musical categories.
This manual-winding movement with a 58-hour power reserve is equipped with a one-minute tourbillon bearing the small seconds hand. Invented at the beginning of the 19th century, this device – which incorporates the escapement as well as the balance-and-spring assembly within a mobile carriage – is designed to compensate for the effects of the Earth’s gravity on the regulator’s isochronism, thereby enhancing its precision.
This tourbillon is distinguished by its carriage shaped like a Maltese cross – Vacheron Constantin’s signature emblem since 1880 – and featuring a bar on which the delicate finishing operations involving manual chamfering and polishing require a full 36 hours of work.
Displayed through the back of the watch on a concave dial designed to accentuate the depth effect, the sky chart offers a striking view of the Milky Way and the constellations that appear in real time, as if through a telescope.
For the sake of accuracy, this sky chart performs a complete rotation in one sidereal day. Taking a fixed star in the sky as a reference point, the time required by the Earth to complete a full 360° rotation, or sidereal day, is exactly 23 h 56 min 4 s. Since the Earth rotates both within itself and around the Sun, it takes about four minutes less than on a calendar day to find its point of origin in relation to the given star.
This sidereal time can be read off counter-clockwise on the 24-hour circle, graduated in 10-minute increments, opposite the current date appearing on a rotating disc with a five by five-day scale. This display is essential for correctly adjusting the sky chart moving beneath the sapphire crystal. The sapphire crystal also bears an off-centred ellipse serving to highlight the exact position of the constellations in the Northern hemisphere at the moment the watch is consulted.
The watch is also equipped with a minute repeater enabling the hours, quarters and minutes to be chimed on demand. To create this particularly complex striking mechanism, controlled by a slide-piece housed in the case middle, Vacheron Constantin’s engineers and watchmakers were inspired by the work carried out on the 2005 La Tour de l’Île watch, and in particular its centripetal strike governor.
This silent system makes it possible to perfectly regulate the duration of musical sequences in order to obtain a distinct and harmonious sound of the notes played for the hours, quarters and minutes by the hammers striking two circular gongs.
Each year, the Les Cabinotiers department unveils a range of single-piece editions relating to a theme cherished by Vacheron Constantin. The year 2021 is dedicated to “Celestial Time”, with timepieces referring to the astronomical origins of time measurement.
In the Vacheron Constantin universe, Les Cabinotiers represents a department in its own right dedicated to the personalisation of Grand Complication models and single-piece editions. This tradition dates back to the 18th century, an age when master-watchmakers were called “cabinotiers” and worked in ateliers bathed in natural light, known as cabinets and located on the top floors of Geneva’s buildings.
In the hands of these learned artisans, open to the new ideas of the Enlightenment, exceptional timepieces were born, inspired by astronomy, mechanical engineering and the arts. This expertise, which constitutes the great Geneva watchmaking tradition, has been flowing through Vacheron Constantin’s veins since 1755.
Model: Les Cabinotiers Minute repeater tourbillon sky chart Leo constellation Jewellery
Calibre 2755 TMRCC
Developed and manufactured by Vacheron Constantin
Mechanical manual winding
33.90 mm (14¾’’’) diameter, 9.40 mm thick
Movement power reserve: approximately 58h
2.5 Hz (18,000 vibrations/hour)
Hallmark of Geneva certified timepiece
Small seconds at 6 o’clock on tourbillon carriage
18K white gold, set with 60 baguette-cut sapphires on the bezel (approx. 3.8 cts), 24 baguette-cut sapphires on case sides (approx. 1.9 cts) and 16 baguette-cut sapphires on lugs (approx. 0.3 ct.)
45 mm diameter, 15.10 mm thick
Dials (front & back)
18K white gold, opaline dark blue dial, Leo constellation hand-guilloché
9 brilliant-cut diamonds as hour-markers (approx. 0.03 ct)
18k white gold hands
Dark blue Mississippiensis alligator leather with alligator leather inner shell, hand-stitched, saddle-finish, large square scales
18K white gold pin buckle set with 16 baguette-cut sapphires (approx. 1 ct)
18k white gold folding clasp set with 16 baguette-cut sapphires (approx. 1.10 cts)
Les Cabinotiers model
“Les Cabinotiers”, “Pièce unique”, “AC” hallmark engraved on caseback