The RM 74-02 offers a ultra-skeletonised tourbillon heart and a unique personality.
RM 74-02 Automatic Winding Tourbillon
Skeletonised automatic-winding tourbillon movement with hours, minutes and variable-geometry rotor:
Power reserve : around 50 hours (± 10%)
The baseplate and bridges of the RM 74-02 are machined from 18K 5N red gold and 18K 3N yellow gold respectively, both microblasted and bevelled by hand.
The skeletonised baseplate and bridges were subjected to intensive and complete validation tests to optimise their resistance capacities
This type of balance wheel represents the ultimate in innovation. It guarantees greater reliability when subjected to shocks and during movement assembly or disassembly, hence 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.
Rotor specifications:
• Heavy outside edge and heavy edge ring in 18K red gold
• Weight segment in platinum
• Automatic OneWay® winding system in ceramic with ball bearings
• Bidirectional winding system
This variable-geometry rotor has been incorporated within the in-house CRMT5 calibre, making it possible to set the rotor according to the owner’s activity level.
The setting is modified by adjusting the two moveable weights into the correct position and fixing them in place with spline screws. The inertia of the movement is increased when the two weights are closer together; the barrel then rewinds more quickly. If the weights are positioned at the extremities of the rotor, the inertia is decreased and the barrel winds more slowly.
MOVEMENT CHARACTERISTICS
- Movement dimensions: 30.70 x 23.70 mm
- Thickness: 6.20 mm
- Number of jewels: 23
- Balance: CuBe, 4 arms, 4 setting weights, moment of inertia of 7.5 mg.cm2, 50º angle of lift
- Frequency: 28,800 vph (4 Hz)
- Balance spring: AK 3
- Shock protection: INCABLOC 908.22.211.100 (transparent)
CASE IN GOLD CARBON TPT®
Gold Carbon TPT® is a high-tech material comprising some 600 layers of parallel filaments obtained by separating out carbon fibres. The layers, no more than 30 microns thick, are impregnated with a black matrix. They are then assembled on a dedicated machine, which stacks the layers, varying the orientation of the fibres by 45° between layers and alternating them with 24K yellow gold leaf layers. As gold is a noble material in chemical terms, it was very difficult for the NTPT and Richard Mille engineers to ensure it ‘fused’ correctly with carbon. The composite is then heated to 120°C at a pressure of 6 bars in a kiln similar to that used for the production of aeronautics parts, after which it is ready to be machined at Richard Mille.
OR IN GOLD QUARTZ TPT®
The RM 74-02 Automatic Tourbillon dons a luminous new attire, cloaked in the ethereal glow of Gold-Quartz TPT®.
In this alchemical blend, the technical resilience of Quartz TPT® intertwines with the timeless allure of gold, creating a material that balances the best of both, modern and tradition worlds. Developed over several years with the brand’s partner, swiss composite expert North Thin Ply Technology, Gold-Quartz TPT® is born from a complexprocess: ultra-thin sheets of quartz fibers are stacked, layer upon layer, then heated to 120° at a pressure of 6 bars. The result is a creation both rugged and refined, with natural striations that form a unique visual tapestry. Within this structure, delicate leaves of 22-carat 5N pink gold are embedded, their warm glow shimmering through the translucent quartz. This union of elements produces an exquisite play of light, a dance between the delicacy of gold and the primal strength of quartz.
The tripartite case is water resistant to 50 metres ensured by 2 Nitrile O-ring seals. The case is assembled with 20 grade 5 titanium spline screws and abrasion-resistant washers in 316 L stainless steel.
Finishing
• Hand-polished anglage
• Hand-polished stepped bevelling
• Microblasted milled section
• Microblasted sinks
• Satin-finished surfaces
• Hand-polished anglage
• Hand-polished sinks
• Burnished sections
• Diamond-polished sinks
• Circular decorations on the front surfaces
• 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 entire going train of the watch, the primary transmitter of power through the movement, utilises a special profile for the teeth of the wheels. Developed specifically for Richard Mille’s in-house calibres, the wheels employ a 20° pressure angle. This system equalises any discrepancies that might arise between the centres of each wheel, for instance, during thermal changes and normal use, and promotes excellent torque transmission to the balance wheel, thus supporting excellent chronometric characteristics.
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.