The Zenith Defy Lab

At its core, the basic process by which a mechanical watch keeps time has barely changed for the last 350-years.

Updates in the form of new cutting-edge materials might improve the accuracy and performance, but the underlying method is pretty much the same now as the one invented by Dutch physicist, mathematician and astronomer, Christiaan Huygens in 1675.

You have a power source (the mainspring) which releases its energy in strictly measured increments, controlled by the escapement and oscillator (the balance wheel and hairspring) working together.

Over the centuries, the system has evolved to offer peak efficiency and precision, but has always kept within touching distance of Huygens’ original invention.

And then there’s the Zenith Defy Lab.

Everything about this 2017 introduction from the Swiss watchmaking innovators—even down to its name—speaks of disruption.

The workings inside the hyper modern shell are a complete departure from the time-honored norm. Here, instead of the traditional sight of springs, wheels and gears all interconnecting and dancing together, there is a single, razor-thin pancake of silicon incorporating 30 different components, vibrating at a positively frenzied rate.

With it, Zenith have managed to negate most if not all of the factors which can cause a mechanical watch to lose timekeeping accuracy—gravity, temperature, magnetic fields, mainspring tension and even the type of lubricant used. The end result is a precision of around 0.5 seconds a day.

Below, we explore this incredible milestone in horology a bit further.

The Technology

The original Defy Lab was released as a concept watch, with only 10 being made. The brand new oscillator in its caliber, the ZO 342, superseded the conventional sprung balance design by including dozens of constituents into one module just half a millimeter thick.

This bizarrely shaped and incredibly complex circular element, 30mm in diameter, was formed from monocrystalline silicon, leaving it completely antimagnetic and invulnerable to temperature variations. The various structures and contours inside the unit were cut using DRIE, or Deep Reactive Ion Etching.

As a whole, the component worked on the principles of compliant mechanics; those which transmit their energy through flexible body distortion. Otherwise known as jointless structures, it means there are no mechanical connections and so no friction, eliminating the need for lubrication.

Looking at the oscillator, it is hard to make any sense of it. There are three main ‘spokes’ radiating out from the center, although all look vastly different from one another. These beams, as Zenith call them, take the place of the traditional hairspring, in that they provide a restoring force to the oscillator. They also have the job of holding the pallets and regulation assembly—the unit’s frequency can be fine-tuned by up to about 300 seconds a day by changing the position of a tiny fork on one of the arms using variable inertia, in the same way as adjusting the active length of the hairspring in a traditional caliber.

The outside rim of the element acts as the balance wheel itself and is divided into three sections. Each section has a pair of oval slits into which sits a tiny pin and makes up the anti-shock system by restricting lateral movement.

In addition, the work of the lever is taken on by two miniscule teeth set into one of the secondary arms that lock and unlock the escape wheel, which is one part not included in the circular mechanism.

In all, there are 20 different flexible elements in the ZO 342’s oscillator, all of differing widths, with the thinnest being a mere 20 microns.

The Performance

The Defy Lab has a frequency of 15HZ, or 108,000vph, an incredible speed even by Zenith’s standards. The brand is no stranger to high beat mechanisms, having built the celebrated El Primero at the end of the 1960s.

But even that caliber and its 36,000vph pales in comparison.

The frenetic pace is helped by an amplitude (how far the balance wheel swings back and forth) of just +/-6°. As a comparison, a normal sprung balance oscillates around 270°+.

It results in not only a silky smooth motion to the seconds hand, but also an accuracy of around 0.5 seconds a day over 48-hours, an amazing precision when you think chronometer ratings from COSC require a variance of -4 to +6 seconds a day.

The construction of the oscillator also ensures it stays accurate to the same degree for 95% of its 60-hour power reserve. With conventional calibers, the unwinding mainspring starts to cause noticeable discrepancies in timekeeping after 24-hours.

The Case

Containing all this groundbreaking technology is a 44mm case forged from another material making its debut.

‘Aeronith’ is touted as the world’s lightest aluminum compound. Molten 6082 aluminum is poured into a mold where it is transformed into a metal foam using a proprietary process first developed by Hublot. The spaces in the foam are then filled in with a hypoallergenic, extremely lightweight polymer, resulting in a composite 2.7 times lighter than titanium and 10% lighter than even carbon fiber.

The Zenith Defy Lab Inventor

The original Defy Lab consisted of just 10 models, each presold to collectors and never made available to the general public.

With the success of their invention (the oscillator actually took the Innovation prize at the 2017 Grand Prix d’Horologerie de Genève) Zenith were able to commercialize their brainchild the following year with the release of the production model, the Defy Lab Inventor.

As well as a better chance of actually being able to buy one, the Inventor also included a couple of other updates.

Firstly, the balance frequency has been upped still further. The ultra high speed 15Hz is now a positively manic 18Hz, or 129,600vph! In addition, the escape wheel on the Inventor is fitted with flexible silicon blades rather than the rigid teeth of the original, allowing for more consistent regulation.

Zenith’s creation is triple certified; it holds ISO 764 for magnetic resistance (exposure to 4,800 A/m), ISO 3159 for thermal insensitivity and the Chronometric+ Observatory certificate from TIMELAB.

Conclusion

The Zenith Defy Lab and Defy Lab Inventor represent something truly exceptional. The biggest breakthrough in mechanical watchmaking in more than 300 years, it is a mesmerizing blend of the very old and the absolute cutting-edge.

While the basic laws of timekeeping have stayed true to Huygens’ original vision, the way Zenith has gone about it has never been seen before.

Featured Photo Credit: BeckerTime’s Archive.