Investigating the inner workings of noteworthy watches. A deep dive into the appraisal of new movements: Part 1: Cartier's "Cal.1928 MC" and light-powered movements.

Since the 2000s, established watchmakers and renowned high-end brands have focused on developing original and spectacular complex movements, competing fiercely for dominance. Furthermore, when a problem arose regarding the monopolization of ébauche movements by some groups, they also strived to internalize the production of basic core movements. However, those days are long gone. Since 2015, with the rise of so-called "luxury sports watches" that have swept the global watch market, key players in the watch market have begun to invest even more resources in exterior design and materials. However, while observing these market trends, some "dedicated" watchmakers have always recognized the importance of developing their own movements and have steadily advanced the research and development of new movements. This article delves into the "must-see" new movements that are the result of their efforts, verifying and explaining their true value.

A movement specializing in design that symbolizes Cartier's evolution.

　The Cartier Privé line now enjoys enthusiastic support from watch enthusiasts. Combining iconic designs from the past with highly reliable movements, Privé represents a modern Cartier approach. However, a model with a completely new movement has been added to the Privé line. The Tortue Monopusher Chronograph, released in 2024, is a masterpiece that showcases Cartier's evolution.

　Cartier has grown significantly under former CEO Cyril Vigneron. By focusing on its iconic designs, improving the quality of its exteriors, and reducing its defect rate by a third, the "jeweler of kings" has established itself as a watchmaker. According to those involved, its failure rate is the second lowest among Swiss watchmakers, demonstrating its considerable capabilities as a watchmaker.

　However, as a consequence, Cartier scaled back its haute horlogerie operations and distanced itself from developing its own movements. This decision may be understandable, given that the company's priority was improving reliability. However, now that it seems to have achieved a certain level of reliability, Cartier has recently begun releasing sophisticated movements. These include the "Mass Mystérieuse," in which the movement itself acts as the rotor, and the "Tortue" monopusher chronograph, which features a remarkably aesthetic movement. The latter is what I would like to discuss today.

　The Cartier Collection Privée chronographs produced by Cartier during its Paris era featured chronograph movements manufactured by the former THA. The design was by the renowned François-Paul Journe. While the appearance was classical, to achieve a thin profile, it employed a horizontal clutch and a swing pinion similar to that of the ETA 7750. However, when creating a new monopusher chronograph, Cartier did not use this excellent movement. The reason was to create a movement suitable for a tonneau case. For the past few years, Cartier has been producing highly versatile movements, but for this limited edition model, they created a monopusher chronograph movement from scratch.

　The priority in the new Caliber 1928 MC, just like in the old THA movement, was "thinness." Therefore, the mainspring barrel is positioned at an extreme offset, and the gear train is also compactly arranged. Since Cartier does not disclose information, the following is speculation. The second wheel, located between the mainspring barrel and the balance wheel, transmits power to the escape wheel via the third wheel (above the central seconds chronograph wheel) and the fourth wheel (above the central seconds chronograph wheel). In this movement, an additional fourth wheel, powered by the escape wheel, is used solely to drive the seconds hand. The unusual (or elaborate) gear train, contrary to its classic appearance, can be understood if we consider that it was designed to accommodate a classic carrying-arm type horizontal clutch while keeping the movement thin. Adopting such an innovative gear train for aesthetic reasons is typical of modern Cartier.

　At the same time, Cartier made the movement's appearance as symmetrical as possible. As the photograph shows, components such as the mainspring barrel and balance wheel, the 30-minute counter wheel and the fourth additional wheel, and the operating lever and chronograph lever are positioned symmetrically. While movements with this kind of design certainly exist, this is probably the only movement where even the regulating springs of the brake lever that stops the operating lever and chronograph wheel are designed to be symmetrical.

　Incidentally, this movement was co-developed by Le Cercle des Horlogers, a company that rose to prominence after working on movements for Louis Vuitton. It's unclear to what extent the company was involved in the design of the Tortue Monopusher Chronograph, but the finishing of the movement is undoubtedly their work.

　The Caliber 1928 MC speaks to Cartier's maturity. I sincerely hope that the Tortue, featuring this movement, will be re-released!

A light-powered watch with significantly improved performance thanks to a new dial technology.

　The second-generation Tank Must SolarBeat™ may seem understated, but it's poised to have a significant impact on the watch industry. The light-powered movement is the same as its predecessor. However, the dial, with its countless tiny holes, greatly improves light-receiving capabilities. Moreover, the dial's texture is that of a high-end metal dial. Will this attempt to combine eco-friendliness and luxury finally succeed?

　A solar-powered movement generates electricity using a solar cell located beneath the dial and stores it in a secondary battery. This electricity then powers a quartz movement. Cartier adopted this technology, which can be considered a Japanese specialty, in the "Tank Must" Solarbeat™ released in 2022. The reason this model quickly became a hot topic among industry insiders is not simply because Cartier had ventured into light-powered technology. It was also because the method of receiving light to the solar cell was completely unique. Because the solar cell generates electricity from a solar cell located beneath the dial, most solar watches on the market use transparent polycarbonate or sapphire crystal for the dial material. In contrast, Cartier chose standard brass. The company chose this material in order to obtain the texture unique to a metal dial.

　Basically, almost all solar cells are purple. Therefore, when a translucent dial is used, the dial inevitably becomes dark. Japanese manufacturers have dramatically improved the texture of solar watches, particularly by improving the finish of polycarbonate, but Swiss manufacturers do not have that level of expertise. The only exception is Tissot, which has developed colorful solar cells, but this is protected by a patent. So how can the texture of a solar dial be improved? Cartier, on the other hand, has found a solution not by choosing a translucent material for the entire dial, but by making only a part of it translucent. Specifically, they cut out the large Roman numerals that are an icon of Cartier and made them receive light from there. Surely this way, it is possible to achieve both the texture of a metal dial and light-receiving ability.

　However, the Tank Must Solarbeat™ design seems to have been too ambitious. As those involved have revealed, the early Solarbeat™ movements were poorly made and their light-receiving sensitivity was not as high as expected. Cartier consistently strived to improve the movement, but the results were not satisfactory. This led to the creation of the second-generation Solarbeat™, which looked almost identical but had significantly altered internal components.

　The key difference with the new SolarBeat™ is its significantly improved light-receiving capabilities. For example, consider the charging time required for a full day's use. Under sunny outdoor conditions, the first generation required 4 minutes, while the second generation takes half that time—2 minutes. The minimum time required to restart the watch has also been halved, from 1 hour for the first generation to 30 minutes for the second generation (under the same outdoor, sunny conditions). Furthermore, performance is even better in low-light environments. Under outdoor shopping mall conditions, it took 112 minutes to charge the rechargeable battery for a full day's use, compared to 48 minutes for the second generation. Power reserve has also increased by approximately five times, from about 5 months to 24 months.

　The trump card of the improved design is the new dial. The previous model used holes in the indices to receive light, but the second generation has tiny holes drilled all over the dial. The material is probably not brass, but a metal or metal-plated material. The finish of the dial seems to have changed significantly, but the light-receiving holes look like they have an extremely matte finish. With this finish, it should be possible to achieve any color that can be achieved with plating or PVD, not just silver.

　Cartier previously stated that the Solarbeat™ movement would be used in models other than the Tank. If the second generation of Solarbeat™ performs as expected, it will undoubtedly change the future of women's watches.