MANUAL WINDING TOURBILLON PHARRELL WILLIAMS
Mankind has looked at Space from the Earth for time immemorial. But with the RM 52-05 Tourbillon Pharrell Williams, the Earth is observed from Mars, a viewpoint expressing one of Pharrell Williams’ dreams. One almost fulfilled in this new model, interpreted by the Creative Development team at Richard Mille: an engraver, an enameller and a painter who, working together, have brought into being an extraordinary piece of contemporary, unconventional watchmaking.
BASEPLATE AND BRIDGES IN GRADE 5 TITANIUM
Grade 5 titanium is a biocompatible, highly corrosion-resistant and remarkably rigid alloy that enables the gear train to function effortlessly. The alloy is 90% titanium, 6% aluminium and 4% vanadium. This combination further enhances the material’s mechanical properties, which explains its frequent use in the aerospace, aeronautics and automobile industries.
The baseplate of the movement features large inserts in dazzling blue aventurine glass that evoke outer space. Also known as ‘goldstone’, this glass glitters due to its triangular and hexagonal copper crystal inclusions. Incorporated into the heart of the RM52-05 calibre, it represents the confines of the universe and all its stars.
FREE-SPRUNG BALANCE WITH VARIABLE INERTIA
The terminal-curve spring equipping this type of balance wheel guarantees greater reliability when subjected to shocks or strong vibrations and during movement assembly and disassembly, hence ensuring better chronometric results over time. The regulator index is eliminated, and a more accurate and repeatable adjustment is possible thanks to 4 small adjustable weights located directly on the balance.
FAST-ROTATING BARREL (6 hours per revolution instead of 7.5 hours)
This type of barrel provides the following advantages:
– The phenomenon of periodic internal mainspring adhesion is significantly diminished, thereby increasing performance,
– Provision of an excellent mainspring delta curve. The choice was determined by the ideal power-reserve/performance/regularity ratio.
WINDING-BARREL TEETH AND THIRD-WHEEL PINION WITH CENTRAL INVOLUTE PROFILE
The central involute profile of the winding-barrel teeth provides an optimal pressure angle of 20°. This promotes effective rotary motion and compensates for possible variations in the engagement of the going train, thus ensuring excellent torque transmission with a distinct improvement in performance.
MOVEMENT CHARACTERISTICS
– Movement dimensions: 32.80 x 30.90 mm
– Thickness: 6.40 mm
– Tourbillon diameter: 10.90 mm
– Balance wheel diameter: 9.12 mm
– Jewels: 19
– Balance wheel: Glucydur®, 2 arms and 4 setting screws
– Moment of inertia: 11.50 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: in nickel-free Chronifer® (DIN x 46 Cr 13 + S) with the following characteristics: stainless antimagnetic suitable for tempering
DECORATIVE BRIDGE, ASTRONAUT’S HELMET
The grade 5 titanium helmet resting on a structure depicting the upper part of a spacesuit, also in grade 5 titanium, connects the dial to the movement beneath it. It has been painted white using an airbrush that was initially developed for street artist Cyril Kongo, who hand-painted the RM 68-01.
The projectors and cameras, represented by two diamonds and a black sapphire set on either side of the helmet, required particular care and attention. The stones are showcased by a moderate gem-setting depth, reflectors that have been polished and bevelled using watchmaking techniques and the alignment of their tables, all of which are facing the same way to ensure a uniform reflection.
To recreate the imaginary Martian scene, the curved 5N gold visor has been engraved using specially created burins, grand-feu-enamelled and then hand-painted. The engraving alone requires 15 hours per piece, followed by an entire day of grand feu enamelling. Pierre-Alain Lozeron had to apply all his patience, skill and dexterity to bring these creations to life.
CASE
The brown Cermet combines the lightness of titanium with the hardness of a ceramic. It consists of a metallic zirconium matrix associated with high-performance ceramic that gives the material its incredible brown hue with metallic reflections.
Cermet has a mass to volume ratio of 5.7 g/cm3 and a hardness of 1,200 Vickers, comparable to a traditional ceramic and making it eminently suitable for use in bezels and case backs, both areas that are highly vulnerable to scratches, while ensuring that the entire assembly is light in weight. These two elements are affixed to a caseband made of Carbon TPT®, which also contributes to lowering the total weight.
This high-tech material is made up of 600 layers of parallel filaments obtained by separating out carbon fibres. The layers, no more than 30 microns thick, are impregnated with a black resin. They are then assembled on a dedicated machine, which stacks the layers, varying the orientation of the fibres by 45° between layers. The composite is then heated to 120°C at a pressure of 6 bars in a kiln similar to those used for the production of aeronautics parts, after which it is ready to be machined at Richard Mille.
The tripartite case is water-resistant to 50 metres, ensured by 2 Nitrile O-ring seals, and is assembled using 24 spline screws in grade 5 titanium and abrasion-resistant washers in 316L stainless steel.
FINISHING
Movement
– Hand-polished anglage
– Microblasted milled sections
– Stretched or polished upper surfaces
Steel parts
– Microblasted surfaces
– Satin-finished surfaces
– Hand-polished anglage
– Long strokes
– Brushed strokes
– Long side strokes
– Polished edges
Wheels
– Diamond chamfering
– Circular decorated faces
– Rhodium plating (before cutting the teeth) Minimal corrections applied to the wheels in order to preserve geometry and performance.
BARREL PAWL WITH PROGRESSIVE RECOIL
This device permits an appreciable winding gain (circa 20 %), especially at the start of winding. It also helps to distribute the internal tension of the mainspring effectively.
CRYSTAL
-Bezel side: in sapphire (hardness of 1800 Vickers) with anti-glare treatment (both sides).
Thickness: 1.50 mm
-Case back side: in sapphire (hardness of 1800 Vickers) with anti-glare treatment (both sides).
Thickness: 1.20 mm
SPLINE SCREWS IN GRADE 5 TITANIUM FOR THE BRIDGES AND CASE
Unaffected by physical manipulation during assembly and disassembly, these screws permit better control of the torque applied to them during assembly and age well.
