The UR-210 by URWERK is well known among watch connoisseurs for its orbital complication and imposing retrograde minute hand. Now the young Swiss watch brand adds an ‘S’ version of UR-210 in a limited edition of just 35 pieces. Dedicated to the aficionados of avant-garde horology, this new version offers even stronger monochrome aesthetic with its full metal bracelet, which was developed specifically for URWERK.
The UR-210’s satellite complication with retrograde minute is both highly original and totally explosive. The principal feature is a high-tech, oversized, three-dimensional retrograde minute hand. Its function is to enclose the hour satellite and indicate the time as it transverses the 0-to-60-minute scale. This one-hour journey through time, tracing an arc of 120°, is smooth and fluid. But the true nature of the piece is revealed at the end of the 59th minute.
Then a sharp distinct “click” signals the return of the minute hand to its starting point. In less than 0.1 of a second the hand flies back to dock with the next hour satellite. This high-speed retrograde system is based on three key elements:
• A central axis set in ruby bearings provides excellent stability for the satellite/retrograde complication. A cylindrical marine chronometer type spring runs vertically around the axis and generates the optimal tension required for the retrograde minutes flyback.
• A minute hand, which also forms a frame for the hour satellites, displays the time in an extraordinary way. Milled from aluminum to exacting tolerances of approximately 3 microns, the whole structure has a total weight of just 0.302g and is counter balanced by a brass weight. This three-dimensional cage offers rigidity as it transfers energy from the cylindrical flyback spring in the top center of the carrousel to the double-star gear underneath.
• A double coaxial star-shaped cam regulates the retrograde mechanism through its gearing and its rotation defines the trajectory of the minute hand. When the minute hand reaches 60, the double star trips a (one of three) hockey stick shaped spring under the mechanism, which liberates the minute to fly back to the next hour satellite at 0-minutes.
The dial of the UR-210S features a traditional power reserve indication at one o’clock. In a near mirror image at 11 o’clock we find a similar indication. No, it isn’t a duplicate fail-safe, but something much more important which deserves our full attention, because it is actually a world-first complication that indicates winding efficiency over the last two hours.
The rotor of the movement converts the slightest movement of the wrist into stored energy. In this configuration, a turbine connected to the rotor provides smooth, unimpeded power. But if you are more active, then that may provide more power than required and unnecessarily wear the mechanism. In that case, you would position the winding efficiency selector to “REDUCED” to engage the rotor damping system.
An air turbine compressor mounted on ruby bearings spins and creates internal resistance – enough friction to slow down or dampen the automatic winding rotor. In “STOP” mode, the automatic winding system is disabled completely and the UR-210 runs off reserve power and may require manual winding.
Model: UR-210S “Full Metal Jacket”
Material: Titanium and steel
Dimensions: Width 43.8mm, length 53.6mm, thickness 17.8mm
Glasses: Sapphire crystal
Water resistance: 30m/100’/3ATM
Escapement: Swiss lever
Frequency: 28,800v/h, 4Hz
Balance spring: Flat
Power source: Single mainspring barrel
Power reserve: 39 hours
Winding system: Self-winding coupled to turbines
Plate in ARCAP P40 rhodium coated; 3D minute hand in aluminum with brass counterweight; central cylindrical spiral in spring-steel; hour satellites in aluminum; central carrousel and screws in Titanium Grade 5
Circular graining, sandblasted, circular and straight satin-finished plate; satin-finished and diamond-polished satellites; beveled and polished screw heads
Patented revolving satellite complication with wandering hour and three-dimensional retrograde minute hand; power reserve indicator; patented winding efficiency indicator
Super-LumiNova treatment on markers, dials, indexes, hands, and satellites
Two-position winding crown with crown protector
On the back: winding efficiency selector
Satin finish; bead-blasted metal bracelet with deployment clasp developed by Maspoli for URWERK