Mechanical perfection is our definition of accuracy.
Through an ample, non-reflective sapphire-crystal display back, the calibre 100.1 movement reveals itself to aficionados of fine timekeeping instruments as a fusion of the arts. Subtly proportioned components in untreated German silver with different types of finissage constitute the individual levels. As was the case in Glashütte pocket chronometers, the movement consists of a main plate and a 2/3 plate precisely spaced apart with two posts and the barrel bridge. Raised gold chatons and pan-head chaton screws add three-dimensional accents. The brilliant glitter of hand-polished chamfers on going-train wheels and the edges of levers and springs resides in the depths of the movement as well.
Several innovations in the calibre 100.1 movement are noteworthy in the ways they further optimise the handling convenience and functional reliability. The newly designed Grossmann balance can now be crafted in-house in its entirety. A further modification of the Glashütte stopwork created space for the Grossmann winder with pusher.
The ATUM breathes at a calming traditional rate of 18,000 semi-oscillations per hour. The calibre 100.1 incorporates the newly designed Grossmann balance and demonstrates that rate accuracy is not achieved solely with a higher frequency. Optimised for artisanal manufacturing techniques, the design of the balance improves the adjustability of inertia and achieves high kinetic energy combined with minimised air resistance and the smallest possible mass. The number of screws in the balance-wheel rim was minimised as well. Mass screws with different head lengths are used to incrementally vary the moment of inertia. Additionally, the rim is provided with uniformly spaced bores that allow reductions in mass or contribute to the poising of the balance. The smooth cylindrical balance staff is integrated in the hub and can easily be replaced if necessary. The Grossmann balance interacts with a Nivarox balance spring which is overcoiled with a quarter arc on the inside and secured to the slotted roller with a brass pin.