Miniaturization has always been one of the main goals of the watchmaking industry. With the advent of complex timepieces and the development of watches, this topic has become increasingly important. Integrating multiple functions into a single movement, while ensuring the wearability of the watch, it is necessary to rebuild the space. This trend, and the desire for elegance, has led to the development of Ultra-thinWatch. It became popular in the 1960s, and was slightly forgotten in the 2000s (the popularity of ‘big’ watches). Nowadays, ultra-thin watches have returned strongly. Major watchmaking brands such as Piaget, BVLGARI and Audemars Piguet are competing.
1997 Piaget Calibre 9P manual winding movement (left); Piaget Calibre 12P automatic winding movement 1960 (right)
The concept of ultra-thin watches is not new, but Piaget and the iconic Altiplano, Piaget, bring it to the spotlight. In 1957, Piaget introduced the thinnest mechanical movement at the time-Calibre9P. This ultra-thin hand-wound movement is only 2 millimeters thick, and the watch assembled will hardly exceed 4 millimeters. Considering the lack of computer-aided equipment of that era, Calibre9P is still considered an incredible improvement to this day.
A few years later, in 1960, Piaget launched the Calibre 12P automatic movement in the same pursuit of slimness. The thickness of this movement is 2.30 millimeters, and it introduces the relatively new concept of Micro-rotor. Self-winding watches are usually equipped with a central rotor, a small rotor, a smaller size, integrated layout, and the same height as the bridge, reducing the thickness of the movement and even the watch. The Calibre9P and Calibre12P movements set the tone for decades of development and gave Piaget the reputation it still enjoys today.
Piaget Calibre 20P movement, its prototype is Jean Lassale Calibre 1200 movement (hand-wound movement only 1.2 mm thick)
The ultra-thin movement is complex and fragile, and few manufacturers are willing to try it, let alone achieve success. However, Piaget is not the only manufacturer involved in the ultra-thin field. Another notable name in the field is Jean Lassale. Calibre 1200, designed by the Swiss watch company, is only 1.2 mm thick and is still the thinnest mechanical movement to date.
In order to achieve extreme slimness, the Calibre 1200 abandons the upper bridge plate and directly fixes all wheel trains (except the balance wheel) on the bottom plate. The spring barrel and the wheel train are suspended and supported by ball bearings. Subsequently, the Calibre2000 automatic winding movement with a thickness of 2.08 mm was successfully developed. Produced from 1976 to 1979, these movements proved to be very fragile (almost impossible to disassemble and repair) and unreliable. Later, the ‘JeanLassale’ name was sold to Seiko, and technical documents and patents were acquired by NouvelleLemania, which continued to produce improved versions of these movements for brands such as Piaget (Lemania1210 and Romania2010) and Vacheron Constantin (Calibre1160 and Calibre1170).
Concord Delirium IV quartz watch slim profile, only 0.98 mm thick
At the same time, the rapid progress of quartz technology has led to the development of ultra-thin watches. The replacement of complex mechanical movements with electronic components opens up even thinner possibilities. The best example of an ultra-thin quartz watch is the ConcordDelirium, which was introduced in 1979. It was the thinnest watch at that time, only 1.98 mm thick. The subsequent release of the Delirium2 watch further reduced its thickness to 1.5 mm. In the end, the Delirium IV watch ended the battle by using the case back as the bottom plate of the movement to achieve an extreme slimness of 0.98 mm. Later, in 1983, Swatch produced plastic watches, and Piaget developed the Calibre 900P movement, both of which adopted this technology.
Although the quartz crisis has had a negative impact on the Swiss watchmaking industry, the ultra-thin race has not stopped. In 1986, Audemars Piguet launched the Ref.25643 watch equipped with the Calibre 2870 self-winding movement. This was the first tourbillon watch produced in the series. Until recently, it was the thinnest tourbillon watch. The extraordinary excellence of the Ref.25643 watch and Calibre 2870 movement is reflected in all aspects. The Ref.25643 watch’s tourbillon frame is extremely small, measuring just 7.2 mm and 2.5 mm in diameter and height, respectively, and made of titanium. The automatic winding function is realized by the ‘pendulum’, not the pendulum. The movement abandons the bottom plate, and the parts are directly fixed on the case back. This is a very clever way to reduce the thickness.
Audemars Piguet Ref.25643, the first tourbillon watch produced in the series, equipped with Calibre 2870 self-winding movement, thickness 4.8 mm
After many years, the concept of ultra-thin watches has returned to the center of the stage. Not surprisingly, thanks to Piaget. Of course, several ultra-thin watches were produced during this period. Patek Philippe has not stopped the production of Nautilus or Calatrava watches (equipped with Calibre 324 or Calibre 240), and Vacheron Constantin, Jaeger-LeCoultre and Audemars Piguet have not abandoned ultra-thin timepieces. In the 2010s, the race for ultra-thin watchmaking resumed, and the last two years have been the new golden age of ultra-thin watches. (Photo / text watch home compiled by Xu Chaoyang)