Calibre L033.1
SEEN THROUGH THE WATCHMAKER’S LOUPE (2 MB)

A WINDOW ON GRACEFUL PERFECTION.

The sapphire-crystal caseback reveals a feast for the eyes of connoisseurs: the lever mechanism of the ZERO-RESTART function is visibly arranged above the three-quarter plate, as is the winding train. Other discoveries include blued steel screws, screwed gold chatons, and a hand-engraved balance cock. As is typical for Lange, all levers, plates, and wheels are meticulously hand-finished.



The balance wheel with eccentric poising weights and the Lange balance spring

FINE-TUNED FOR PRECISION.

The manually wound calibre L033.1 movement is tuned to the ultimate in accuracy as can be legitimately expected of a scientific instrument used for synchronising timepieces. Its precision is derived from a large balance wheel with eccentric poising weights as well as a balance spring developed and manufactured in-house. It beats at a rate of six semi-oscillations per second. The interaction of the balance and the balance spring was optimised in exhaustive research work involving many series of tests.


The function of the ZERO-RESTART mechanism

MECHANICAL FINESSE.

A lever that acts on a zero-reset heart cam is one of the core elements of the new ZERO-RESTART mechanism. It causes the small seconds hand to instantaneously jump to zero when the push piece is actuated. At the very same moment, a vertical disc clutch uncouples the fourth-wheel arbor from the power transmission of the movement. This allows the hour and minute hands to continue to run without any loss of accuracy even while the push piece is kept pressed.