TRADITION · PRECISION · PERFECTION - Erwin Sattler

Nautis
Dimensions: Diameter 21 cm Depth 9 cm Weight 9.5 kg
Bronze-nickeled
Nautis – Sattler Precision at Sea or in Your Own Home
At the Erwin Sattler manufactory, mechanical precision clocks
have been lovingly manufactured in small series for almost fifty
years. These first-class timekeepers of the art of clockmaking
are among the best of what is available in this genre
worldwide. In this spirit, marine clock Caliber 1395 was
developed over the course of several years.
This movement is simultaneously reliable, low maintenance,
and durable – and meets the highest standards on land and
at sea. Its spring barrel stores energy for an entire fifteen day
period; therefore it only needs to be wound every two weeks.
The precision of any mechanical timekeeper depends on how
constantly energy is transmitted from the spring barrel to the
escapement. Caliber 1395 contains a gold-plated Swiss lever
escapement on the back of the movement, the heart of which
is a classic, certified screw balance that has been regulated
for weeks according to strict criteria and a high-quality
balance spring. Mainsprings have the basic disadvantage
that their torque is not constant from beginning to end.
Naturally, when they are fully wound they contain more energy
than at the end, something that influences the amplitude of
the balance’s oscillations. Sattler compensates this with a
very artful, technical trick.
This »trick« involves the most difficult of all solutions that the
physical law of levers can supply. The longer the lever, the
less energy is needed to perform a certain task. To the
contrary, if the lever is short additional energy is needed.
In Caliber 1395, the task of the lever is taken on by a
precisely calculated fusee with a robust steel cable.
The initial spring energy – which is also the strongest –
corresponds to the smallest rotation of the fusee. The slowly
decreasing torque of the mainspring is compensated by the
continuously increasing diameter of the fusee. Because the
fusee rotates backward during the winding process, and the
movement has no energy during this time, the clockmakers
have built an intelligent power-maintaining mechanism into
the movement. Its design was invented by John Harrison,
and it guarantees a constant flow of energy even while the
clock is being wound.
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