Now only striking watches like minute repeaters and grande sonnerie are still regarded as exclusive grand complications in the traditional sense; both the rattrapante chronograph and tourbillon have been made accessible with technology.

A tourbillon was challenging to produce because of the tiny parts involved; components of the tourbillon require tolerances of fractions of a millimetre. In the past, those tiny bits had to be made by hand. Today modern manufacturing techniques like spark erosion make it possible to automate the fabrication of such parts (click here  for a look at component manufacture at Daniel Roth). In fact, a certain independent watchmaker once said it is possible to fabricate and install a flying tourbillon in a movement in a week.

Close-up of Daniel Roth 8-Day Tourbillon in platinum

That being said, finishing and adjustment of high-end tourbillons (think 6-figure price tags) is still as difficult as ever. Much of the value in a tourbillon lies in the hand finishing, especially of the tourbillon itself. Polishing a tourbillon bridge a couple of millimetres in length to the speculaire, or black, finish that is de rigueur for a high horology tourbillon can take hours.

Another shot of the 8-Day Tourbillon; note the polished steel bridge 

Daniel Roth, as well as most other haute horlogerie manufactures, assembles tourbillons atelier style - one watchmaker creating one watch - instead of on an assembly line, further upping the cost of production. Needless to say, more affordable tourbillons do not feature most of the top level hand finishing or assembly found in upper end watches; the STT (formerly Progress) flying tourbillon widely used in entry-level tourbillons looks and feels industrial (when it was unveiled in 1999 the cost of the Progress tourbillon movement was a mere $3500 or so). Another (in)famous tourbillon, the Jaeger-LeCoultre Master Tourbillon, is a notch above the STT calibre but still a far cry from the top-end high horology tourbillons.

It might be hard to believe but a couple of years ago tourbillon watches were confined to the upper reaches of the price spectrum. In those days Lemania had the market for tourbillons cornered; the choice was either to make a tourbillon in-house or buy the Lemania cal. 387. Daniel Roth was then dependent on Lemania, not surprising since Daniel Roth the man played a part in the resurrection of Breguet and Lemania in the 1970s.

After the acquisition of Breguet and Lemania by Swatch, Daniel Roth decided to create its own tourbillon calibre so as to ensure future supply of movements. That resulted in the creation of the cal. 720 8-Day tourbillon, which at the time was the only such movement in the world. Since then Daniel Roth has added a further 3 in-house tourbillon calibres in its stable: cal. 780 skeleton tourbillon found in the Tourbillon Lumiere, cal. 730 tourbillon with retrograde date and power reserve, cal. 740 tourbillon with perpetual calendar and automatic winding. (For an excellent article on the genesis and manufacture of the Daniel Roth 8-Day Tourbillon, see Alberto Schileo’s definitive work here .)

Daniel Roth 8-Day Tourbillon in platinum

Daniel Roth Tourbillon Lumiere

Daniel Roth Tourbillon with Perpetual Calendar

Daniel Roth Tourbillon with Retrograde Date; piece unique for Only Watch 2007

All of Daniel Roth’s tourbillons are one minute tourbillons of the archetypal bridged type, where the tourbillon carriage is support by a bridge on one side and pivoted on the other. As a result of being one minute tourbillons, whereby the tourbillon carriage makes one rotation every minute, the tourbillon regulator is fitted with the 3-pronged seconds hand, a trademark of Daniel Roth.

Daniel Roth 8-Day Tourbillon with trademark 3-armed seconds hand

Two more types of tourbillon regulators are fairly common. One is known as the flying tourbillon - the ‘flying’ moniker comes from the fact that there is no bridge holding up the cage and the carriage is supported by the pivot only. Flying tourbillons, as well as the bridged tourbillon, have the balance wheel and tourbillon cage rotating on the same axis. In contrast, another kind of tourbillon known as the carrousel has the balance and cage on two separate axes, consequently the balance wheel in a carrousel tourbillon is smaller. Some traditionalists consider this type of tourbillon a non-tourbillon (this is a matter of some controversy).

Flying, bridged or carrousel - what does a tourbillon actually achieve in a wristwatch? In my humble, amateur opinion - not very much.

A tourbillon was originally conceived to improve timekeeping by compensating for errors in gravity, because clocks and pocket watches were often kept in vertical positions which had an effect on the balance - that does happen apply to wristwatches. Furthermore, modern manufacturing techniques allow for the creation of very accurate watches sans tourbillon regulators. Anecdotal evidence is inconclusive, some tourbillon owners swear by the extraordinary timekeeping of their watches, but others report that the only benefit is watching the cage rotate (a lot more fun than it sounds).

- SJX

Detail of the first generation Daniel Roth 8-Day tourbillon; photo courtesy of Peter Chong