The Double Tourbillon 30° “Asymmetrique” is the latest new watch from the Anglo-French alliance of UK-born Stephen Forsey, and his partner and co-founder at Greubel Forsey, Robert Greubel, who was born and raised in Alsace –it’s the first time their first invention –a concentric double tourbillon, with the inner cage inclined 30 degrees with respect to the outer –has been presented in this design.
The partners met at Renaud & Papi (now Audemars Piguet Renaud & Papi) where Greubel was COO and a partner; Stephen Forsey worked with him as a complications specialist and prototypist. In 2001, the two founded their own complications specialist firm –Complitime, which has created (as a very discreet silent partner) some of modern watchmaking’s most sophisticated complicated watches –and in 2004 they launched the company that bears their name.
Greubel Forsey makes a very small number of watches every year –in an especially profligate year they might crack a hundred –and all their timepieces (with the exception of the Double Balancier 35°) are tourbillons; the signature complication is their double tourbillon 30°. The idea was to make a tourbillon that’s suited to a wristwatch –the classic tourbillon produces a single averaged error in rate for all the vertical positions, but was designed (by Breguet, in 1801) for the only kind of watch that existed then: the pocket watch. The wristwatch is placed in many different positions throughout the day (unlike pocket watches, which are usually either vertical in the pocket, or horizontal on a table) and by inclining the inner carriage with respect to the outer, the escapement and oscillator system are prevented from ever finding themselves in a position where rate error is maximized (that is, the most extreme positions are avoided by the design.)
GF watches are somewhat intellectually demanding. One must know that the rate of the watch changes with respect to changes in position due to gravity; one must understand the motivation behind Breguet’s original invention; one must understand the problems inherent in adapting the tourbillon to a wristwatch; and finally, one must understand how the inclined double tourbillon attempts to address these problems. The reward for the effort, though, is a sense of satisfaction in having the watch on the wrist which is matched by few other timepieces; it’s on a continuity of experimentation in mechanical horology which represents some of the most interesting inventions in watchmaking, as well as centuries of effort to solve some of watchmaking’s most basic problems.
The technical sophistication isn’t limited to the oscillator system, however; every other aspect of the watch has been optimized for performance and efficiency. This is necessary for several reasons, but basically it’s a question of realizing the theoretical advantages of the design in reality; as Stephen Forsey likes to remind people, it’s always a question of gaining more than you lose by introducing more complexity into the design. For instance, the tourbillon was historically considered an extremely difficult type of regulating device to construct (horological traditionalists sometimes object to calling it a complication, as it doesn’t deliver any additional information; it’s a hair-splitting point but does underscore the tourbillon’s real functionality.) The reason is simple: the tourbillon sits at the far end of the going train of the watch, where available torque has been dramatically reduced by the gearing of the train. In an ordinary watch the remaining torque need only move the lever and impulse the balance; in a tourbillon, on the other hand, you need to have enough power at each oscillation of the balance to overcome the inertia of the entire oscillator system –the balance and hairspring, as well as the lever and escape wheel –as well as the inertia of the tourbillon cage that carries them. In the Double Tourbillon 30° the problem’s compounded by the use of two tourbillon cages –the outer, which rotates once every four minutes, and the inner, which rotates once per minute.
This problem has been dealt with in part by altering the gearing of the going train so that the mainspring barrels rotate more rapidly. Think of riding a bike with multiple gears –when you go uphill, you change gears so it takes less force per revolution of the pedals to keep the wheels turning; the trade-off is that the pedals turn faster. The Double Tourbillon 30° has two fast-rotating barrels which despite their more rapid revolution still provide 3 days (72 hours) of running time. (This is the official power reserve –the real running time until the watch stops would be longer but the practical power reserve is given as 3 days, since the reduction in torque beyond that is less than what’s necessary for optimal performance.) Another benefit of this approach is a reduction in side-load on the going train pivots, which means reduced friction throughout the train –this means better rate stability as well as much less friction related wear.
The watch is full of such attention to design and technical detail, and the rewards of getting to know what has gone into it, as well as where it’s located in a horological history of ideas, are considerable. But like every watch Greubel Forsey makes, it’s also watchmaking at the highest level both in terms of aesthetics, and in terms of the synthesis of aesthetics and engineering that’s almost unique to watchmaking as a craft. Part of the cost in making such an object is in the design complexity, and part of it is in making each component to the requisite precision in extremely small numbers. A very significant cost, however, is in the finishing of each component, every one of which –and there are 326 parts in this particular GF watch –is finished by hand to the highest standards.
The finish and architecture of Greubel Forsey watches reflects, unsurprisingly, both the French-Swiss and English watchmaking vocabularies. Most readers will be familiar with the French-Swiss approach, with its signature use of Geneva waves and multiple bridges; many will be less familiar with the English approach, which reached its highest evolution in the hand-made, high grade English pocket watch of the late 19th and early 20th century. English makers typically preferred reassuring, overbuilt solidity to the lyrical grace of French-Swiss watchmaking, and rather than full-bridge movements most top tier English makers preferred a 3/4 plate layout, with a frosted gold finish. The beauty of the English approach is much more restrained and less apparently seductive to the eye but there’s a sober purity to the contrast between firegilt plates, flawlessly black-polished steel, and heat-blued screws that gives English watches a seductiveness all their own.
The movement of the Double Tourbillon 30° Asymmetrique is very much an evolution of the English idiom, with a quiet dignity that radiates confidence in its own excellence. It’s in diametric opposition to the superficially flashy display back finish found on so many watches, but look closely and you start to lose yourself in it –perfect, sharply executed inner corners (still the signature of hand-applied anglage; machine finishing can’t produce such sharp inner corners and they still have to be done by hand) and gorgeously done countersinks for the jewels are just some of the evidence of the (very time consuming) level of finish applied to the watch.
Though the Double Tourbillon 30° Asymmetrique is, at least in terms of visible architecture and finish, perhaps slightly more a reflection of the English approach, I’d like to leave you with a quick view of another Greubel Forsey watch: the Double Tourbillon 30° “Technique.” Here, the mainspring barrels –which are side-by-side in the Asymmetrique –are stacked, rotating on the same axis; this results in a slightly thicker but more compact design. The open dial exposes the top plate architecture, which with its extensive use of cocks and bridges is very much in the French-Swiss heritage; it’s an intriguing integration of the two schools of watchmaking.
The Double Tourbillon 30° Asymmetrique is an extremely expensive watch. It’s also going to be extremely rare; Greubel Forsey plans to make a total of 22, with 11 planned in white gold and 11 in 5N red gold. The case is 16.13mm thick and at its widest diameter, 43.5mm; the balance is free sprung, adjustable mass, the balance spring has a mathematically correct Phillips terminal curve. $545,000 and frankly you can spend that much on quite a lot of other watches that offer far, far less. For more information visit www.greubelforsey.com.