Returning for a second year as the timing partner at the Goodwood Festival of Speed, Roger Dubuis celebrated the occasion with the launch of the Excalibur Spider Flyback Chronograph. A watch based on new research with an openworked dial showing off the proprietary RD780 calibre, which combines an inclined balance wheel with an integrated chronograph movement. What makes the latest release important are two elements. First, the complex movement, with two patents pending, has elaborate and unusual features like a digital minute counter and twin barrels for the main spring, along with diamond-coated silicon escapement parts, which are both wear and magnetism resistant. Second, the new Excalibur Spider is part of the “bleed down” technology that the Monovortex concept watch (read our review HERE), released at this year’s Watches & Wonders, represents.
A comparison between the Roger Dubuis Monovortex (left) and the Excalibur Spider Flyback Chronograph (right) showing the inclined escapement and minute counter.
Roger Dubuis’s current designs distinguish themselves through bold visuals and eye-catching features. In the process, they are developing a unique approach to hyper-mechanical design, where the style and the technical elements place the watch in the same field as others using esoteric new materials and proprietary chronograph calibres. The RD780 Excalibur is arguably more sophisticated than others in the same arena because of the features found in the Monovortex concept watch, particularly the inclined escapement, digital counter, and unusual chronograph construction that has the levers on the back but the column wheel visible on the dial (at 6 o’clock).
It is the latest addition to the Excalibur Spider collection, which is characterised by skeletonised carbon-ceramic composite cases. The dial has double chronograph scales on its periphery: an inner flange tachymeter scale, and an outer flange that carries the minute track, all highlighted with alternating white and red accents. On the outermost edge, beyond the minute track, there is a ring bearing the rhodium-plated, hex nut-shaped hour markers, filled with Super-Luminova. The white gold hour and minute hands are likewise openworked, filled with the same luminescent material at the tips and outlined in red.
Detail of the dial showing the inclined balance wheel (bottom left), chronograph minute counter (top right) and realigned column wheel (bottom right).
The RD780 flyback chronograph movement features both a column-wheel and a vertical clutch, with a power reserve of 72 hours, twin barrels visible at the top of the movement and two patent-pending innovations — one for the chronograph’s seconds hand, and the other for the 120° Rotating Minute Counter (RMC).
The first patent concerns the clutch mechanism known as the Second Braking System (SBS), which improves the stability of the chronograph seconds hand and reduces any stuttering when pressing the start, stop, or reset buttons. In the SBS, the brake is directly mounted on one of the two arms that operate together to engage or disengage the vertical clutch. When the chronograph is stopped, these two arms lift the vertical clutch to disengage it, while the brake simultaneously prevents the seconds hand from moving. The chronograph pushers are light, yet responsive, and with the movement incorporating the SBS, the seconds hand counts exactly and stops instantly. Visually, and in a tactile sense, it is a step up in the function of mechanical chronographs.
The caseback of the Excalibur Spider Flyback Chronograph showing the design of the automatic rotor, which mirrors the wheel rims of the Lamborghini cars, and the traditionally finished movement.
The second patent, for the 120° RMC, located at 3 o’clock, enables the elapsed minutes to be read without a conventional sub-dial. The minute display features three rotating arms carrying the digits “0”, “1”, and “2” respectively. The arms rotate and progress along the outer scale bearing the second digit of the minutes. It is an original and expeditious way of including the minute count dial in a chronograph.
As in other Excalibur models, the RD780 also sports a balance wheel inclined at 12 degrees from the horizontal to compensate for gravitational errors, while increasing the inertia of the balance. Alongside the balance is a diamond-coated silicon escape wheel and diamond-coated silicon pallet jewels that are both hard-wearing and non-magnetic. The Excalibur Spider Flyback Chronograph is not only an innovative new watch from Roger Dubuis, combining new technology, space-age materials, along with traditionally finished watchmaking, but it also provides an indicator of how they will incorporate their hyper horology into production models in the future.
Available only through Roger Dubuis boutiques, £87,000.
Words: Dr Andrew Hildreth