RM 018 TOURBILLON "HOMMAGE A' BOUCHERON 518.06.91/D

TECHNICAL SPECIFICATIONS OF THE RICHARD MILLE TOURBILLON RM 018 “Hommage à Boucheron”

CALIBER RM018: manual winding tourbillon with hours, minutes.

Dimensions: length 48 mm x 39.70 mm x 12.80 mm

MAIN FEATURES
(MANY OF WHICH ARE MAJOR TECHNICAL INNOVATIONS)

POWER RESERVE
Circa 48 hours.

MOVEMENT WHEELS IN SEMI-PRECIOUS STONES
The RM 018 represents the first time that it has been possible to create a number of wheels inside the movement using semi-precious and precious stones such as tiger-eye, jasper, black onyx and diamonds. The technique behind their creation required a high level of mathematical modeling in order to control the process of manufacturing, taking more than three years of development and testing before a perfect result was to be found. The wheels, once constructed, are each given a sunray pattern profile, created entirely by hand, in the ateliers of Boucheron at 26, Place Vendôme Paris. In this way the RM 018 represents the ultimate example of what can be achieved by the transformation of ancient materials into horological impulses, using skills from the historic traditions of the jeweler’s craft to create a world premiere 21st century timepiece.

PLATES CREATED FROM SYNTHETIC SAPPHIRE Al2O3
This represents the total elimination of the baseplate structure by the use of two full sized, transparent plates that act as bridges supporting the entire movement. The rhomboidal crystalline structure of synthetic sapphire crystal Al2O3 , in combination with its high melting point of 2,303 Kelvin and minimal thermal coefficient of linear expansion (6 x 10-6) , make it exceptionally stable even under conditions far outside those of normal use. It also possesses an abrasion stability eight times higher that of steel.

WINDING BARREL AND COVER FROM SYNTHETIC SAPPHIRE Al2O3
This not only allows a view of the watch’s internal structure: it also eliminates temperature discrepancies between the movement and winding barrel’s ambient temperature since both have the same temperature coefficient, thus providing additional stability to the movement.

TEETH OF BARREL AND THIRD WHEEL PINION WITH CORRECTED INVOLUTE PROFILE
The corrected profiles of the teeth allows a double pressure angle of 10° and 20°, thus effectively promoting smooth movement and compensating possible variations of engagement. This ensures excellent torque transmission and a distinct improvement in performance.

OTHER FEATURES
• Movement dimensions: 31.20 x 28.20 mm
• Thickness: 6.68 mm
• Diameter of the tourbillon cage: 10.90 mm
• Diameter of the balance wheel: 10 mm
• Number of jewels: 29
• Balance wheel: GLUCYDUR, 2 arms.
• Moment of inertia: 10 mg.cm2, lever angle 53°
• Frequency: 21,600 vph (3 Hz)
• Balance spring: ELINVAR by NIVAROX
• Shock protection: KIF ELASTOR KE 160 B28
• Jewels set in white gold chatons
• Barrel shaft: in chronifer without nickel (DIN x 46 Cr 13 + S), which has the following characteristics: non-oxidizable – antimagnetic – hardened.

CRYSTAL
• Bezel side: In sapphire (1800 Vickers) with anti-glare treatment (2 sides).
• Thickness: 1.20 mm
• Case back: In sapphire with anti-glare treatment (2 sides)
• Thickness: at the center 1 mm and outer edges 1.73 mm

FLANGE (upper and lower)
In carbon fiber with index points filled with approved luminous material.

FINISHING

MOVEMENT
• Anglage and polishing by hand
• Locking sections hand polished
• Sapphire blasted milled sections
• Lapped and polished contact points
• Burnished pivots

STEEL PARTS
• Sapphire blasted surfaces
• Satin-finished surfaces
• Anglage and polishing by hand

WHEELS AND TEETH
(Applies to all metal as well as semi-precious, precious/metal wheel combinations)
• Concave chamfering with a diamond tool
• Circular finished faces
• Gilding (before cutting the teeth)
• Minimum manual correction to the wheels undertaken in order to preserve geometry and performance