Magnetism

Magnetism is what happens when a watch's movement — most often its hairspring — is exposed to a magnetic field strong enough to magnetise its steel parts. The classic symptom is sudden, dramatic time-gaining: a watch that kept good time yesterday runs minutes fast today. It is one of the most common faults in modern watch ownership, and one of the easiest to put right.

Why a magnetised watch runs fast

The hairspring is a hair-thin spiral that expands and contracts with every beat, governing the rate. Made of steel in most movements, it is vulnerable: expose it to a strong field — a handbag's magnetic clasp, a tablet cover, a loudspeaker, some phone accessories — and adjacent coils of the spring can become lightly magnetised. The coils then cling to each other instead of breathing freely, the spring effectively shortens, and the balance beats faster. The watch has not been damaged in any mechanical sense; its timing has been hijacked by physics.

Resistance is not immunity

Modern watches fight back better than their ancestors. Many recent movements use silicon hairsprings, which are not ferromagnetic at all, and some certified anti-magnetic models withstand fields that would stop older watches outright. But the majority of watches in collections today still carry steel springs, and "anti-magnetic" on a spec sheet always names a tested limit, not an exemption. The everyday sources are unglamorous — bag clasps and fridge magnets have claimed more fine watches than any MRI machine.

What it means for your winder

Two things. First, diagnosis: if a watch on your winder suddenly gains time, suspect magnetism before suspecting the winder — a winder cannot make a watch run fast, but a magnetised hairspring will, on or off it. A watchmaker can confirm with a demagnetiser pass, a job of minutes. Second, the hardware itself: a winder contains a motor, and motors involve magnets, which is why quality winders shield their motors and keep them at a working distance from the watch — our watch winders use magnetically shielded motors for precisely this reason. It is one of the less visible differences between a well-engineered winder and a cheap one.

Frequently asked questions

How do I know if my watch is magnetised?

The signature is sudden time-gaining — minutes per day, appearing overnight — in a watch that previously kept time. A compass held near the case back may twitch near a magnetised movement, but a watchmaker's test is definitive and the demagnetising itself is quick and inexpensive.

Can magnetism permanently damage a watch?

In ordinary cases, no. Demagnetisation restores the spring's behaviour completely. The harm is to your schedule while the watch runs fast, not to the movement itself.

Does a watch winder cause magnetism?

A properly designed one does not — its motor is shielded and positioned away from the watch. Magnetism in collections overwhelmingly traces back to the magnetic clutter of daily life, not to winding equipment. (If the concept of a watch winder itself is new to you, that entry is the place to start.)

Where should I store watches to avoid magnetism?

At home, distance is the whole strategy: a watch box or drawer kept away from loudspeakers, magnetic phone mounts and tablet covers will rarely meet a field worth worrying about. Ordinary household life is not dangerous — it is close, prolonged contact with strong magnets that does it.