The rotor completes almost 2000 full revolutions, for instance, until the imposing IWC automatic movement is fully wound. Someone who moves a lot will achieve this in just a few hours. In the case of a careful owner, who occasionally takes the watch off, it can take up to a day. “The main problem with designing a mechanism like this is to find a compromise that suits everyone, regardless of how much they move,” explains Gäumann. For this reason, early on in the development phase, Schaffhausen’s automatic movements are put through their paces by a range of testers with very different lifestyles.
In everyday use, the automatic winding system is exposed to all kinds of stresses and strains. Although the rotor weighs only a few grams, the massive forces exerted on the components during rapid movements may be as much as 1000 times that of gravity. In some models, the rotor is protected against severe impacts by a spring-mounted bearing. Although the way the Pellaton winding system functions has remained fundamentally unchanged for over 60 years, it has still undergone continuous improvement. Today, for example, the pawls are ceramic and virtually impervious to wear and tear. For the 89000 chronograph calibre, the entire mechanism has undergone a thorough overhaul. The resulting double-pawl winding system does the job with fewer parts and, thanks to the use of two pairs of pawls, is even more efficient.
So whether manually or through the wearer’s own movements, both systems reliably serve their purpose of supplying the watch with energy and bringing the delicate mechanism to life. But ask devotees which of the two mechanisms is better or more beautiful and the answers are as different now as they will be in a hundred years.