We love the challenge yachts face: exploiting as much of the wind’s enormous energy as possible, transforming it into efficiency in order to win a given race while constantly adapting to reduce resistance to a minimum. We really wanted to express the powerful inspiration that racing yachts represent for us, as thoroughbred machines blending cutting-edge technology and an essential artistic harmony with nature.
As the theme of ocean racing inherently involves a mastery of time and the management of time zones, it was vital to incorporate a second-time-zone complication into this timepiece.
RM 015 TOURBILLON MARINE
Manual-winding tourbillon movement with hours, minutes, second time zone, function selector, power-reserve and torque indicators.
Circa 70 hours (± 10%).
This is an isotropic composite material created from carbon nanofibres moulded under pressure of 7,500 N/cm2 at a temperature of 2,000˚C, resulting in a material with high mechanical, physical and chemical stability in all directions. The ribbed perimeter of the movement baseplate ensures the highest rigidity of the baseplate and bridges.
Carbon nanofibre composite structures such as this are amorphous, chemically neutral and dimensionally constant within a very wide range of operating temperatures, including those outside of normal experience. This stability ensures optimal integrity of the movement’s going train under all conditions.
BRIDGES MADE OF GRADE 5 TITANIUM
These components, crafted in grade 5 titanium, confer great rigidity on the whole assembly, as well as the precise surface flatness essential for perfect functioning of the gear train.
CENTRAL BRIDGE IN STAINLESS STEEL
This provides optimised stiffness and corrosion resistance.
DUAL TIME ZONE INDICATOR
This dual time-zone indicator is technically extremely complex, while at the same time very user-friendly. At the centre of the dial, a transparent sapphire crystal disc inscribed with hours permanently rotates through the movement. The digits on the disc are visible only when transposed on a clear background, situated at 10 o’clock.
This dual time zone is quickly and easily adjusted using the finely finished pusher situated at 9 o’clock. Each push adds an extra hour to the time zone.
FUNCTION SELECTOR
In a manner similar to a car’s gearbox, a push-button located at the centre of the crown makes it possible to select the winding, neutral and hand-setting functions with a simple push. A hand at 4 o’clock displays the selected function.
TORQUE INDICATOR
This indicator supplies information about the mainspring’s tension, thus permitting an optimisation of the movement’s chronometric functioning. Below 53 Nmm, the spring is considered too slack, while above 65 Nmm, excess tension in the spring can adversely affect the mechanism’s operation, or actually endanger.
POWER-RESERVE INDICATOR
The power-reserve indicator shows the number of hours of energy left in the mainspring before the watch must be wound again.
FREE-SPRUNG BALANCE WITH VARIABLE INERTIA
The free-sprung balance offers better reliability in the event of shocks, movement assembly or disassembly, and also guarantees better chronometric results over time. The regulator index is eliminated, and a more accurate and repeatable calibration is possible thanks to 4 small adjustable weights located directly on the balance.
MODULAR TIME-SETTING MECHANISM FITTED AGAINST THE CASE BACK
This mechanism provides the following advantages for longevity and maintenance:
• Since the component is mounted outside of the movement, the time-setting assembly can be changed without affecting the integrity of the baseplate in the event of a possible defect or during maintenance.
• The mounting and dismantling of this module from the back does not require removal of the hands or dial.
MOVEMENT CHARACTERISTICS
Movement dimensions: 30.20 x 28.60 mm
Thickness: 6.35 mm
Tourbillon diameter: 12.30 mm
Balance wheel diameter: 10.00 mm
Number of jewels: 23
Balance: Glucydur®, 2 arms, 4 setting screws, moment of inertia 10 mg•cm2, angle of lift 53°
Frequency: 21,600 vph (3 Hz)
Balance spring: elinvar by Nivarox®
Shock protection: KIF Elastor KE 160 B28
Barrel shaft: nickel-free Chronifer® (DIN x 46 Cr 13 + S) with the following characteristics: stainless – antimagnetic – suitable for tempering
CASE
The design and execution of the watch demonstrate a holistic approach to conception of the movement, case and dial. As a result, everything has been constructed according to extremely rigorous specifications, in the manner of the analytical engineering methods used in the design of Formula 1 racing cars, where the chassis and the engine are developed in complete harmony. Features such as these are evidence of uncompromising workmanship.
Producing this case requires more than 47 preliminary procedures, followed by 255 milling operations before completion. Machining lasts 4 hours. Finishing work demands a full day for each watch.
The tripartite case is water resistant to 50 metres, ensured by 2 Nitrile O-ring seals. The case is assembled with 12 spline screws in grade 5 titanium and abrasion-resistant washers in 316L stainless steel.
Finishing
• Anglage and polishing by hand
• Hand-polished locking sections
• Sapphire-blasted milled sections
• Lapped and polished contact points
• Burnished pivots
• Sapphire-blasted surfaces
• Anglage and polishing by hand
• Concave chamfering with a diamond tool
• Circular-finished faces
• Rhodium plating (before cutting the teeth)
• Minimal corrections applied to the wheels in order to preserve geometry and performance.
Other features
This type of barrel provides the following advantages:
The central involute profile of the winding-barrel teeth provides an optimal pressure angle of 20°, which promotes effective rotary motion and compensates for possible variations in the operation of the going train. This, in turn, ensures excellent torque transmission and a distinct improvement in performance.
This permits better control of the torque applied to screws during assembly. These screws are therefore unaffected by physical manipulation during assembly or disassembly and age well.