H. Moser Endeavour Minute Repeater Cylindrical Tourbillon Skeleton Cosmic Rain

H. Moser & Cie. has unveiled the Endeavour Minute Repeater Cylindrical Tourbillon Skeleton Cosmic Rain, a limited edition of 20 pieces that pushes the boundaries of haute horlogerie. This timepiece masterfully combines a minute repeater, a flying tourbillon with a cylindrical hairspring, and extensive skeletonization—a triple threat of mechanical complexity. The Cosmic Rain edition adds an artistic aventurine and mother-of-pearl dial that evokes a meteor shower, enhancing the visual spectacle.

A Legacy of Chime and Motion

H. Moser & Cie. first introduced a minute repeater paired with a tourbillon in 2019, exposing both complications on the dial side. This was a bold move, as traditional minute repeaters often hide their hammers and gongs on the movement's reverse. The 2019 version placed the chiming mechanism between 9 and 11 o'clock, allowing wearers to witness the hammers in action. The new skeletonized iteration takes this concept further by revealing the entire movement architecture.

Skeletonization as a Complication

Skeletonization is often considered a complication in its own right, requiring the removal of excess material while maintaining structural integrity and precision. Moser's radical approach demanded a complete rethinking of the movement. The curved gongs, essential for the minute repeater, had to be positioned on the same plane as the flying tourbillon and its cylindrical hairspring, avoiding any interference. Tuning curved gongs is notoriously challenging, even more so than round ones. Each gong is hand-filed to achieve the correct pitch, ensuring harmonious chimes.

The heavily skeletonized bridges and plates are hand-finished with Moser's hallmark double stripes, revealing a fascinating three-dimensional mechanical landscape. The only solid element on the dial is the small blue aventurine sub-dial at 2 o'clock for hours and minutes, which serves as a striking contrast to the openworked panorama.

The Cosmic Rain Dial

The main novelty of this edition is the dial, designed to recreate a meteor shower. The sparkling aventurine glass is traversed with mother-of-pearl inlays, suggesting shooting stars across a night sky. To achieve Moser's signature fumé gradient, two different tones of blue aventurine glass fragments are applied by hand to the domed base and then fired multiple times. After firing, thin, curved strips of iridescent mother-of-pearl are applied to cutout areas, resulting in a classic fumé effect with a lighter center and darker periphery. With no indices to disturb the celestial scene, time is indicated by elegant leaf-shaped hands.

The Flying Tourbillon with Cylindrical Hairspring

At 6 o'clock, a one-minute flying tourbillon is fitted with a cylindrical hairspring, a feature borrowed from 18th-century marine chronometers. Produced by Moser's sister company, Precision Engineering AG, the hairspring is shaped by hand. Set in a deep well that receives light from both sides, the hairspring rises perpendicularly around the upper stem of the balance staff, a mesmerizing sight that underscores the watch's technical prowess.

Case and Acoustics

The Cosmic Rain is housed in a 40mm x 14.4mm titanium case with a hollowed-out middle to create a resonant soundbox. Titanium is an ideal material for minute repeaters because it does not suppress or absorb vibrations, unlike platinum or gold. Its low density and high rigidity enhance the volume, clarity, and duration of the chimes. The case is equipped with a sliding bolt on the caseband, featuring a Teflon runner for smooth activation of the repeater.

Movement and Specifications

Powering the watch is Moser's manual-winding calibre HMC 909. Measuring 33mm x 9.6mm, the movement comprises 415 components and 35 jewels. It operates at a frequency of 21,600 vibrations per hour (3Hz) and delivers a robust 90-hour power reserve. The movement is fully skeletonized and hand-finished, with every component decorated to Moser's exacting standards.

The watch is paired with a hand-stitched grey nubuck leather strap with an alligator pattern, secured by a titanium pin buckle featuring the Moser logo. The reference is 1909-0501, and it is limited to 20 pieces, priced at CHF 378,350 including taxes.

Collector's Perspective

This timepiece represents a pinnacle of Moser's craftsmanship, combining acoustic excellence, mechanical complexity, and artistic dial work. For collectors, it offers a rare opportunity to own a watch that showcases the brand's innovative spirit and technical mastery. The limited production ensures exclusivity, making it a significant addition to any serious collection.

For more information, visit H. Moser & Cie. directly.