Watch Servicing and Care: How to Maintain a Mechanical Watch

A mechanical movement is a system of metal parts running against each other, lubricated by tiny amounts of oil. Over years, the oil migrates and dries, friction increases, and the parts begin to wear. Servicing cleans the movement, replaces the lubricants, and adjusts the regulation, restoring both accuracy and longevity.

A watch that is never serviced does not stop immediately — it runs less accurately, then less reliably, and eventually a worn part fails. Service is preventive, not reactive.

A common guideline is every three to five years for an automatic movement, though modern synthetic lubricants have extended practical intervals for many calibers. The right interval depends on use: a daily-wear watch needs service sooner than one worn occasionally.

Signs that a watch needs service include a sudden change in accuracy, a stuttering second hand, or difficulty winding. Any of these is a reason to have a watchmaker look at it rather than wait for a complete stop.

Water resistance depends on rubber gaskets that degrade over time. A watch rated to 100 meters when new may not maintain that rating after several years, because the gaskets compress, dry, and lose their seal. For regular water exposure — swimming, diving — have the pressure tested annually.

Avoid operating the crown or pushers underwater; that opens a path past the seals. After saltwater exposure, rinse the watch in fresh water to prevent corrosion. A watch that has been opened for service should always be pressure-tested before it is returned.

Magnetic fields — from speakers, phone chargers, laptop hinges, magnetic clasps — can magnetize a movement's balance spring, causing it to run fast, sometimes dramatically so. Magnetism is common and, fortunately, easily fixed: a watchmaker can demagnetize a movement in minutes, often at no charge.

If a watch suddenly gains several minutes a day, magnetism is the first suspect. It is not damage to the movement; it is a temporary condition that a demagnetizer corrects.

• Store the watch away from strong magnets and direct, prolonged sunlight on the dial.
• Avoid shocks — mechanical parts are small and can be damaged by hard impacts.
• If the watch has stopped, wind it with a few crown turns or wear it to restart; do not shake it violently.
• Keep the crown pushed in and screwed down (if applicable) unless you are setting the watch.

These are small habits, but they are the difference between a watch that runs for a decade and one that needs early repair.

Use a watchmaker who is familiar with the movement in your watch. For widely used calibers like the NH35, almost any competent watchmaker can service it; parts are inexpensive and the architecture is well understood. For less common movements, confirm the watchmaker can source parts before sending the watch.

A good service includes cleaning, lubrication, regulation, and pressure testing. It is not a quick job, and a watchmaker who returns a watch in two days has likely not done a full service. Expect several weeks for a proper one.