Beyond The Bezel: The Tourbillon

If you’ve been pursuing an interest in luxury watches for any time at all, you’ve probably heard of a tourbillon. But what actually is it? And why do timepieces that contain one cost so much?

This fascinating complication is the pinnacle of haute horlogerie. But despite being both delicate and complex, it has little to no effect on the accuracy of a movement. The question of why luxury watch fans love tourbillons so much has nothing to do with mechanics. And everything to do with obsession. To answer it, we have to dive into the very heart of your timepiece.

The Great Escape

A mechanical movement marks time with its balance spring and its balance—a wheel-shaped device powered by the escapement. In watches, the escapement is made up of an escapement wheel (a toothed gear) and levers, also called pallets, which alternately lock and release the teeth of the escapement wheel. Think of a pendulum swinging from a clock—hidden from your view are the two pallet forks, which trap the cogs in the escapement wheel. Every time the pendulum swings, the pallet forks allow the clock’s escapement wheel to ‘escape’ for one beat.

This movement causes the balance to oscillate. Each oscillation is regulated by the balance spring, which returns the balance to a central position after it moves. The regulation creates a resonant or harmonic frequency, which effectively controls the speed with which the watch gear train advances.

As the gear train advances, the hands move, and time is kept.

This combination of escapement and balance, working ideally in harmony, dictates the accuracy of the watch. But reality is never as perfect as theory. Actually, the balance oscillates at a varied frequency, sometimes a little too fast and sometimes a little too slow. And so your luxury watch, over time, begins to lose or gain seconds. The Swiss Official Chronometer standard (COSC), which is applied to pretty much all high-end watches, is a certification that the movement maintains an accuracy within -4/+6 seconds per day. Some luxury watches, like Rolexes, carry their own standard: Rolex’s Superlative Chronometer badge is a sign that your timepiece is at least twice as accurate as an Official Chronometer.

Balance, or Balance Wheel?

In watchmaking, a wheel is a gear with teeth. A balance, while shaped like a wheel, is toothless, and so is often referred to as a balance, not a balance wheel.

The Quest For Perfection

Luxury watch manufacturers have long been vexed by the gap between the accuracy of their movements and the passage of true, regulated time. Abraham-Louis Breguet, the granddaddy of haute horlogerie, invented the tourbillon in the late 18th century as a proposed solution to the problem.

Breguet believed gravity had a negative effect on the accuracy of the balance. His theory was derived from the fact that, as pocket watches are normally kept in pockets, they are basically held in one unmoving position for much of the day. Perhaps, Breguet surmised, the delicate balance spring lost accuracy as gravity worked on it over the course of a day.

In other words: he believed that the resonant frequency of the balance was expanding and contracting as the weight of gravity pulled on the balance spring. And so he decided to do something revolutionary—literally. He decided to make the whole escapement move in a circle. And the tourbillon was born.

In essence, what Breguet’s tourbillon did, and still does, is this: it puts the escapement and balance in a cage, and spins it around so it cannot remain stuck in one position. By turning the escapement and balance on an axis, the tourbillon supposedly averages out the effects of gravity.

Imagine a rubber band, suspended between two nails. Now hang a weighted hook on it. The rubber pulls down towards the floor, and over time that one part of the band becomes weakened, and breaks.

But now imagine that the whole thing, band, hooks, and all, is on a wheel. As the wheel turns, the hook-weight changes the direction in which the rubber band is stressed. So overall, the stress is equalled out over multiple sections. That’s a tourbillon. As it turns, the weight of gravity keeps shifting, and the balance is mildly stressed all over, rather than heavily stressed at one point.

The Magic of Movement

It is this motion that causes most fans of luxury watches to fall in love. The first time you see a tourbillon working, it’s like magic. Crazily revolving in its cage, it appears to be an independent, living thing, a clockwork bird trapped in a forest of cogs and springs.

The tourbillon cage as a whole must still be attached to the movement, or the escapement and balance cannot cause the gear train to advance. And yet when you watch it, it looks like it’s floating. For the luxury watch enthusiast, this optical illusion is a moment of mechanical brilliance that more than justifies the price of a tourbillon timepiece. For the luxury watch manufacturer, it’s a point of pride and a great differentiator. If you want to create a stir, or get your loyal collectors reaching for their wallets again, you create a tourbillon version of a signature timepiece—a tactic employed by Audemars Piguet with the tourbillon Royal Oaks and Royal Oak Offshores. Or you develop a luxury sports watch that contains a tourbillon capable of withstanding the shock of actual sporting wear: like Richard Mille, whose tourbillon models have appeared on Centre Court at Wimbledon, and in the cockpit of F1 racing cars.

The Unnecessary Solution

As far as modern horological science can tell, there’s either negligible or no gravitational effect on the accuracy of a luxury watch. Or, at least, there’s no evidence that the tourbillon really cancels out deficiencies in the watch’s accuracy caused by gravitational pull. And that makes the tourbillon an elegant solution to a problem that doesn’t really exist.

The tourbillon has lasted so long, and commands so much respect, because of its brilliance: not as a solution to a problem, but as a machine that probably shouldn’t work at all. The complex engineering leaps required to make a balance that revolves within its own movement, yet still connects to the gear train (which remains static, and thus constantly changes its orientation to the tourbillon), are such that they defy the comprehension of the mortal mind.

The more complicated and obscure the leap, the more deeply we fall in love with the results.

That’s why the most audacious and impressive tourbillons of all are the most expensive. Luxury watch lovers translate enthusiasm willingly into price tags, particularly when they’re paying for a complication that only exists to show that it can be done. The multi-axis tourbillon, for example—the height of the horologist’s art—defies the laws of physics not once but on multiple planes. It moves like a gyroscope, rotating the balance within a sphere instead of a circle. In theory, this allows it to cancel out gravity on every conceivable plane. In practice, as we’ve seen, it doesn’t really do anything. But it looks absolutely awesome. And it states, loud and clear, the income bracket of its owner. Tourbillons are status symbols for luxury watch collectors, and watches with multiple tourbillons, all beating away on multiple axes, are the biggest status symbols of them all.

You don’t buy a tourbillon watch because it’s better at keeping time than any other luxury watch. You buy it for the same reason the watchmaker created it in the first place: because you can. Creating a tourbillon is a time-consuming, costly business, and the end result must be hand-assembled and inserted carefully into the movement. The more intricate the tourbillon, the longer and costlier the process. That’s why only the most established brands, with the biggest pots of money to throw at design, R&D, material purchase, and hand manufacture, can afford to develop luxury watches that showcase these fantastic but essentially useless devices. Or, at least, that was the case. Until 2016, when TAG Heuer unveiled the Carrera Heuer 02-T.

TAG Heuer Carrera Heuer 02-T

The TAG Heuer Carrera Heuer 02-T changed the tourbillon game forever. The world’s most affordable Swiss-made tourbillon chronograph, ever, featured a flying tourbillon (a tourbillon where the bridge has been removed at the front, so the cage appears to be ‘flying’ in midair) at 6 o’clock, was made from titanium and steel, and retailed for the jaw-dropping price of £12,152 in mid-2016 money. Jaw-dropping, that is, because before the Carrera Heuer 02-T, the cheapest Swiss-made tourbillon watch retailed at around £50k.

Relatively affordable, or astronomically out of most collectors’ leagues (check out the Jacob & Co Astronomia Tourbillon for a real tourbillon grail piece), tourbillon watches are one of the great joys of luxury watch appreciation. You’ll never forget the first time you put one on your wrist. And from that moment on, even if it’s at a trade show and you have to give it back, you’ll be hooked.