Fantastic calibers and where to find them: THA's 045MC for Cartier

In our in-depth examinations of fantastic movements in modern independent watchmaking, we’ve covered Urwerk’s ultra-innovative EMC, Moritz Grossmann’s HAMATIC with its Breguet-inspired automatic winding system, and Greubel Forsey’s Double Balancier à Différentiel Constant. Each of these deep dives covers one caliber, built usually with one watch in mind. Today, we’re changing gears slightly to take a look at an amazing caliber that appears and reappears throughout recent history in indie watchmaking. That is the 045MC – originally crafted for the now, highly collectible Cartier Tortue Monopoussoir CPCP ref. 2396B. 

Crafted by Techniques Horlogères Appliquées (THA) SA in the mid- to late-1990’s, the 045MC attracts attention because it was designed and developed by the firm’s three, now renowned co-founders – François-Paul Journe, Denis Flageollet (later, co-founder of De Bethune), and Vianney Halter. While the caliber itself is a novel and interesting design for a monopusher chronograph, a large part of its importance lies in what it inspired in the years after its first appearance in the Cartier catalog. Today, we’re taking a deep look at Caliber 045MC and following its evolution throughout the years across De Bethune, F.P. Journe, and Angelus.

The Cartier Torture Monopoussoir, the first timepiece with the THA 045MC caliber (Credit Sotheby’s)

Caliber 045MC, the details

Crafted for the Collection Privée Cartier Paris, abbreviated as CPCP, this was Cartier’s attempt to re-establish its watchmaking capabilities. THA was contracted to create a movement for the Tortue Monopoussoir, launched originally in 1999. 

What made this movement significant isn’t solely that it occupies a niche in horological history, co-created by three future stars of modern independent watchmaking. The Caliber 045MC uses an oscillating (or sliding) pinion to connect the chronograph with the gear train. This vertical clutch system offered significant advantages to the overall footprint of the movement, fitting the requirements for a rather slim profile and small case (43mm x 35mm x 10mm). There was really no alternative for the watchmakers. The underlying movement was based on a Peseux design, thin at 2.5mm and providing enough torque to power complications. Halter, Flageollet, and Journe were able to design and develop a chronograph module that fit the parameters set by Cartier, sliding into a mere 1.7mm of room left. 

THA’s 045MC in the Cartier Tortue Monopoussoir CPCP (Credit Sotheby’s)

Besides the engineering required to create an exceptionally slim chronograph movement, the vertical clutch system provides further chronometric improvements to the movement, one that influences the overall smoothness of activating the chronograph. The vertical clutch set-up reduces the load on the going train, compared to horizontal clutch systems, which minimizes the loss of amplitude in the balance. The minimized load is what makes the activation of the chronograph so soft – there’s no violent jump common in many chronographs from 0 to 1 second. 

One thing that’s important to note here, there were very few chronographs manufactured in this period, especially relative to today. The 1990s in the watch industry was very much still rebuilding in the fallout of the Quartz Crisis. This caliber was unveiled roughly a year before the highly esteemed A. Lange & Söhne Datograph released the brand’s in-house chronograph caliber (L951.1).

“An idea can change the world…” 

Part of the lasting legacy of this movement, what makes it fantastic, is that it lives far beyond the confines of its first casing. We observe that both Denis Flageollet and François-Paul Journe return to this architecture in each of their ventures – De Bethune and Journe’s eponymous brand. It reappears with modifications in the DB1 – the first De Bethune timepiece – as well as in the DB8. It’s the inspiration for Journe’s Chronographe Monopoussoir Rattrapante.

De Bethune’s DB8 with movement based on modified THA’s caliber

Some of the changes that occur over time, specifically observed in the DB8, is that this timepiece features only one subdial at six o’clock. It is very easy to mislabel this a “time-only” watch with a small second subdial. Known as a “soccer timer,” the six o’clock subdial features a 45-minute counter for the chronograph (one half in a soccer match). A central chronograph seconds hand moves front and centered when the complication is activated.

Franck Muller Long Island timepiece crafted by Jacquet S.A, before becoming La Joux-Perret (Credit Monochrome Watches)

Further variations of this movement appear in the early 2000’s in Ulysse Nardin, Franck Muller, Baume et Mercier, as well as Bucherer monopusher chronograph timepieces. This was all a function of the rights to manufacture Cal. 045MC were bought by Jacquet S.A, a movement manufacturer that interestingly later became La Joux-Perret. La Joux-Perret Manufacture is watchmaking behind Angelus and Arnold & Son timepieces, as well as many high-end ébauche movements supplied to the industry. 

Angelus’ Instrument de Vitesse with its modified movement based on THA’s caliber

The creation of THA, the renowned trio of indie watchmakers, has moved from its origins in the Cartier Tortue Monopoussoir through the catalogs of many other brands. Of course, each one of these steps through watch history comes with its own modifications. With Angelus, the Caliber A5000 is based on the architecture of the 045MC, but is not a pure copy. Just as Denis Flageollet transformed elements of the 045MC in the DB1 and DB8, Angelus retains the oscillating pinion, vertical clutch system for its small footprint. The architecture of the A5000 has changed significantly though. With the chronograph module and very little space in the ultra-compact 045MC, the A5000 is more spread out (going from 24mm to 25.6mm in diameter) and provides collectors with more to admire in the mechanics of the chronograph complication. Here, there’s balance struck in the evolution of the 045MC – it’s a well designed and architected chronograph without any of the usual bulkiness often synonymous with the complication. Found in Angelus’ Instrument de Vitesse, it’s spectacular to see the continuous evolution of this caliber. 

Quality isn’t always a function of spectacular complication and complexity. Rather it’s mechanics that stand the test of time, resurfacing again and again. These bedrock movements become important pillars in watchmaking history, as is the case in the 045MC. Whereas other deep dives into fantastic calibers focus on the spectacle of a given movement’s innovation, the 045MC qualifies for its enduring presence in modern watchmaking. Inspiration for monopusher chronographs, Caliber 045MC has evolved, watch by watch, in the catalogs of different brands for more than 25 years. Only time will tell where it appears next, and how it may appear further different and improved.