Launched in 2021, Richard Mille's collaboration with Ferrari resulted the ultra-thin mechanism measuring 1.18 mm height. The hand-wound RM UP-01 movement is enclosed in an unusual 51mm x 39mm, 1.75mm-thick case consisting of two flat components bolted together by 13 screws. This is an essential feature of the extraordinary architecture of the movement because the closest competitors, in the race for the thinnest mechanical watch used the back of the case as the mainplate of the watch (Bulgari Octo Finissimo Ultra - 1.8 mm, Piaget Altiplano Ultimate Concept - 2 mm).
In the Richard Mille RM UP-01 watch the traditional winding crown has been replaced by a flat knob, to winding the mainspring of the watch and to settings the hands, placed on the front plate of the case. The similar second flat knob is used to select the “crown” operating mode. Both settings are made using a special key tool supplied with the watch. The hands are also not typical, one of them is made in the form of a rotating openwork disc. The frequency of the movement is 4 Hz, and the power reserve is 45h. Due to the dimensions of the watch and the size of the parts of the movement made of accuracy tolerances of 1 micron only, all elements are manufactured exclusively by the Richard Mille.
The movement and the tonneau-shaped case are made of grade 5 titanium, an alloy of 90% titanium, 6% aluminum and 4% vanadium. It’s a widely used titanium alloy, particularly highly resistant to corrosion, it's very stiff, and very dimensionally stable under a wide range of temperatures. The stiffness of the material was essential for the envelope and movement in view of practical wearability of the watch, as well. Although applied the extraordinary architecture of the watch, two sapphire crystals of thickness up to 0.45 mm were used to shield the time indication and the balance. Also, this exacting construction offer 10m waterproofness rating and can withstand accelerations of over 5,000 G’s.
The unique hyper-thin architecture RM UP-01 was developed by the team of engineers Richard Mille and Audemars Piguet Le Locle (formerly Audemars Piguet Renaud & Papi). The design of the escapement does not include the guard pin (conventionally attached to the anchor fork) and safety roller.
In the Swiss anchor escapement these elements prevent from locking up of escapement. The use of the guard pin and safety roller increases the overall height of the movement equipped with a Swiss escapement.
In the escapement RM UP-01 to eliminate locking up of escapement and reduce the overall thickness of the movement as an alternative to the traditional guard pin it was decided to use in-house side-lever configuration. To limit motion of the anchor, a specially shaped plate with a cutout (in the line with the Geneva Seal requirement) which allowed to reduce the overall height of the movement was used.
How it works, it can be seen in the video below from about 50th second.
The ultra-thin movement was used in the hyper-flat Richard Mille RM UP-01 Ferrari watch, which was produced in 150 pieces at a price of $ 1,888,000.
PS. The title of the thinnest movement in the world still probably belongs to the Vacheron Constatnin and the movement of the pocket watch ref. 10726 with an impressive thickness of 0.94 mm!
Notifier: Tomasz Jakubas
Other records: Timeline of Watchmaking Innovations