AN INSPIRED UNDERTAKING
RM 70-01 TOURBILLON ALAIN PROST
BASEPLATE AND BRIDGES MADE OF GRADE 5 TITANIUM
The baseplate and bridges are crafted of grade 5 titanium, a biocompatible, highly corrosion-resistant and remarkably rigid alloy, which enables the gear train to function effortlessly. The alloy is 90% 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. The baseplate is black PVD treated.
The skeletonised baseplate and bridges were subjected to separate and extensive validation tests to ensure they met rigorous strength requirements.
The mechanical odometer can tally distances of up to 99,999 kilometres, but it can also serve as a reminder, since the mechanism makes it possible to set specific dates or times.
Adjusting the odometer is done using two grade 5 titanium pushers. Located at 2 o’clock, the first pusher is a selector that can synchronise any of 5 selected rollers, or set the complication in neutral position. Depressing the second pusher, at 10 o’clock incrementally rotates the selected roller. Inspired by the gear indicators on the handlebar gearshift, markers on the odometer provide visual confirmation of the selection.
As this function occupies the greater part of the movement, the calibre needed to be as compact as possible, which was achieved by positioning the winding barrel and the tourbillon on the same axis.
Movement dimensions: 37.10 x 29.73 mm
Thickness: 10.70 mm
Tourbillon diameter: 12.40 mm
Balance diameter: 10.00 mm
Number of jewels: 32
Balance: Glucydur®, 2 arms, 4 setting screws, moment of inertia 10.00 mg•cm2, angle of lift 53º
Frequency: 21,600 vph (3 Hz)
Balance spring: elinvar by Nivarox®
Shock absorbers: KIF Elastor KE 160 B28
Barrel shafts: nickel-free Chronifer® (DIN x 46 Cr 13 + S) with the following characteristics: stainless – antimagnetic - suitable for tempering