RM 50-03
THE WORLD’S LIGHTEST SPLIT-SECONDS TOURBILLON CHRONOGRAPH
We couldn’t have dreamt of a more fitting partner than McLaren. The brand strives to achieve perfection—whether it be in research and development, aesthetics or execution, right down to the smallest detail. With our ten-year partnership, we are really only at the beginning of exploiting opportunities and transfers of know-how between our two companies. Yet the collaboration has already borne fruit with the RM 50-03, the lightest mechanical chronograph ever produced.
Produced in collaboration with the famed Formula 1 team, the RM 50-03 is a technical masterpiece offering off-the-chart mechanical performance. The split seconds chronograph ultralight McLaren F1 weighs merely 38 grams, strap included, making it the world’s lightest split-seconds tourbillon chronograph. This achievement is attributable to the use of highly technical materials: not only do titanium and Carbon TPT® make for an extremely open design, but an entirely new material has been introduced for the case, namely Graph TPT®.
A SHARED DEDICATION TO TECHNICITY AND DESIGN
An extraordinary avant-garde automotive constructor, possessed of an unrivalled heritage and history, McLaren has been inspiring passion for over half a century. Richard Mille has tremendous admiration for this pillar of motorsports, and its founder. Indeed, he has long drawn on technical solutions developed by engineers at McLaren and adapted them for his watches. Naturally, their shared dedication to technic and design has led the brand and team to pursue joint developments.
GRAPH TPT® : A REVOLUTIONARY MATERIAL
The RM 50-03 introduces an entirely new material into the world of watchmaking: Graph TPT®, which contains the revolutionary substance, graphene. These new applications for the material emerged through research at the National Graphene Institute, established in 2015 at The University of Manchester, where graphene was first isolated by Professor Andre Geim of the School of Physics and Astronomy, back in 2004. Six years later, the discovery earned its author the prestigious 2010 Nobel Prize in physics, alongside his colleague, Professor Konstantin Novoselov. Thanks to the collaborative work between The University of Manchester, McLaren Applied Technologies and North Thin Ply Technology (NTPT®), Richard Mille has succeeded in producing a watch case machined in an improved form of Carbon TPT®.
The carbon’s physical properties were significantly enhanced by the introduction of graphene, a revolutionary nano-material which is six times lighter than steel and 200 times stronger. McLaren Technology Group and McLaren, which are currently working on integrating graphene into their Grand Prix cars, made it possible for us to consider this material as a means to significantly lower the density of the carbon composite while increasing its resistance. Convinced of the incredible advantages conferred by graphene, our engineers worked with those at North Thin Ply Technology to envision practical applications of the new material and studied how to incorporate it into Carbon TPT®. Exhibiting a distinctive, damascene surface, Carbon TPT® is made up of 600 layers of parallel filaments obtained by separating out carbon fibres.
These layers, no more than 30 microns thick, are impregnated with a graphene-containing 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 hardened in a kiln heated to 120°C at a pressure of 6 bars. Numerous control and validation tests conducted by McLaren Applied Technologies made it possible to develop the solutions that resulted in Graph TPT®, a material employed exclusively by Richard Mille in the domain of watchmaking.
RM 50-03 TOURBILLON CHRONOGRAPH McLAREN F1
CALIBRE RM50-03
Manual winding tourbillon movement with hours, minutes, split-seconds chronograph, 30-minute totaliser, and power-reserve, torque and function indicators.
Limited edition of 75 pieces
POWER RESERVE
Circa 70 hours (± 10%), without the chronograph running.
Actual power reserve results will depend on the period of time the chronograph is utilised.
ULTRALIGHT TOURBILLON CALIBRE IN TITANIUM AND CARBON TPT®
The Calibre RM50-03 weighs just 7 grams and fully deserves its qualifier ‘ultralight’. The secret to its feather weight lies in the use of grade 5 Titanium and Carbon TPT®, and in the extreme skeletonisation of components. Likewise, the density, stiffness and low thermal conductivity of titanium make it a material of choice in McLaren Racing’s Formula 1 engineering build programme.
BASEPLATE AND BRIDGES IN GRADE 5 TITANIUM
The baseplate and a portion of the bridges are crafted in grade 5 titanium, a biocompatible, highly corrosion-resistant and remarkably rigid alloy, which enables the gear train to function effortlessly. The alloy is 90% grade 5 titanium, 6% aluminium and 4% vanadium. This combination further increases the material’s mechanical properties, which explains its frequent use in the aerospace, aeronautics and automobile industries.
Some of the bridges belonging to the split-seconds chronograph are made from Carbon TPT®, as is the transverse carriage supporting the entire calibre, together with the barrel and tourbillon bridges. Attached to the caseband, this carriage circumvents the need for a casing ring, allowing the movement to be perfectly integrated into the case.
All of these technical solutions give this complex calibre—with its extreme weight to resistance ratio—an impressive resistance capacity, tested in our workshops to shocks of 5,000 g’s.
NEW SPLIT-SECONDS SYSTEM
The Calibre RM50-03 introduces a latest-generation split-seconds mechanism developed by the Richard Mille engineers. Design of a new split-seconds mechanism and extensive research on the work of the split-seconds clamps have permitted a 50% reduction in the chronograph’s energy consumption, while at the same time reducing arbour friction.
The 6-column wheel that controls the various rockers for the split-seconds function was designed to guarantee flawlessly simultaneous movement, clean function lock, and highly stable settings.
FUNCTION INDICATOR
In a manner similar to a car’s gearbox, the function indicator makes it possible to see the winding, neutral and hand-setting positions as the crown is pulled out. The active position is indicated via a hand at 4 o’clock pointing to the following functions: W (Winding) – N (Neutral) – H (Hands).
TORQUE INDICATOR
This indicator supplies information about the mainspring’s tension, 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 it.
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
This type of balance wheel guarantees greater reliability when subjected to shocks and during assembly or dismantling of the movement, thus providing better chronometric results over time.
The index is eliminated, thereby allowing a more precise and repeatable calibration using 4 setting screws.
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 with an ideal power reserve/performance and 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°, 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.
MOVEMENT CHARACTERISTICS
Movement dimensions: 31.10 x 32.15 mm
Thickness: 10.02 mm
Tourbillon diameter: 12.40 mm
Balance wheel diameter: 10.00 mm
Number of jewels: 43
Balance wheel: 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 highly conceptual holistic approach to the movement, case and dial. As a result, everything has been constructed according to extremely rigorous specifications, in the manner of analytical engineering methods used in the design of Formula 1 racing cars, where the chassis and the engine are developed in complete harmony. For example, a casing ring is no longer used, and the movement is mounted on chassis mounting rubbers (ISO SW) fixed by grade 5 titanium screws. Features such as these are evidence of uncompromising workmanship.
The case in Graph TPT® of the RM 50-03 is water-resistant to 50 metres thanks to two Nitrile O-ring seals. The case is assembled with 20 spline screws in grade 5 titanium and abrasion-resistant washers in 316L stainless steel.
UPPER AND LOWER FLANGES
In Carbon TPT® filled with an approved luminescent coating.
TORQUE-LIMITING CROWN
This additional security system prevents accidental overwinding, which could cause damage to the winding stem or put extreme pressure on the barrel spring.
The shape of the crown takes its cue from the racing competition wheel rims used by the British team, while the hollow pushers of the chronograph recall the air intake ducts on the McLaren F1 car.
Finishing
Movement
• Hand-polished bevelling
• Hand-polished locking sections
• Sapphire-microblasted milled sections
• Lapped and polished contact points
• Burnished pivots
Steel parts
• Wire-drawn and microblasted surfaces
• Hand-polished bevelling
Wheels
• Concave chamfering with a diamond tool
• Circular-decorated front faces
• Rhodium plating (before cutting the teeth)
• Minimal corrections applied to the wheels in order to preserve geometry and performance.
Other features
BARREL PAWL WITH PROGRESSIVE RECOIL
This device permits an appreciable winding gain (circa 20%), especially during the start of winding. It is also helpful in ensuring an even distribution of the mainspring’s internal tension.
MODULAR TIME-SETTING MECHANISM ON THE CASEBACK
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 the removal of the hands or dial.
SPLINE SCREWS IN GRADE 5 TITANIUM FOR THE BRIDGES AND CASE
The design of these screws permits better control of the torque applied during assembly. These screws are therefore unaffected by physical manipulation during assembly or disassembly and age well.