TECHNIQUE18.10.2023 Breguet 1815 8 min read

Chronometer Tolerances

Balancing Poise and Hairspring Breathing

FIG 1.0 — Micro-machining lathe used for horological component creation

Analyzing the dynamic poise of vintage balance wheels and static terminal curves.

Achieving COSC precision standards in vintage mechanical movements requires micro-adjustments to the Breguet overcoil terminal curve.

When static poise is perfected using dynamic poise washers, the rate variation across 5 positions stabilizes to within +/- 2 seconds per day.

TECHNICAL SPECIFICATION

Movement Benchmark: Breguet 1815

SWISS HOROLOGY ARCHIVE

CHRONOCODILE LABORATORYHorological Preservation & Restoration Journal