Faced with a mechanical watch that refuses to start, the novice watchmaker can quickly feel at a loss. Yet a seasoned professional knows that a simple visual diagnosis is often enough to identify the fault in seconds.

One of the first things to check is the condition of the balance. Observing the movement in profile under the loupe, give the balance a slight impulse. If it oscillates unevenly or stops abruptly, there is a good chance the balance staff is broken. This is a classic fault that occurs after the watch has been dropped: the microscopic pivots (as thin as a hair) that support the balance shatter on impact.

Developing this sense of observation and diagnosis is one of the most rewarding skills in the watch repairer's trade.

Diagnosis is taught methodically in Unit 3 of the online watchmaking course; the underlying theory is summarised in how to learn watchmaking online.

Learn to read inside movements. Décalibre's online curriculum trains you in diagnostic and repair techniques so that every fault finds its logical solution.