The Movement Clinic · Self-test
How to check your watch for magnetism and demagnetize it
Applies to any mechanical watch, not only Tudor — this is one of the seven procedures in the section that isn't brand-specific.
Why this test works
A compass is unreliable: a compass needle is a magnet, so it's attracted to any ferrous mass — a steel case, steel plates, a steel bracelet — whether or not that mass is actually magnetized, and a mildly magnetized hairspring deep inside a steel case can gain minutes a day without visibly moving a needle. The rate log is the best owner-level detector — magnetism's signature is sudden, fast and persistent, a large gain that appeared abruptly after a specific event. Gradual drift is wear, not magnetism.
What you need
- A mains-powered demagnetizer — about $15-25 for the common blue puck style. This is the actual fix, not just a diagnostic.
- Skip phone magnetometer apps entirely — the phone itself contains speaker magnets, a vibration motor, camera OIS, and on iPhones a MagSafe array, so it can't tell the watch's field from its own.
The steps
- If you try the compass test anyway, bring the watch in, note the swing direction, then rotate the watch 180 degrees and repeat from the same distance. This flip check is our own synthesis, not a published protocol — treat it as a sanity check, not a verdict.
- Place the watch dial-down on the pad, press and hold the button, slowly withdraw to about 30cm while still holding the button, and only then release. The withdrawal-while-energized is the entire mechanism — releasing the button while the watch sits on the pad can leave it more magnetized.
- Repeat 2-3 times, rotating the watch 90 degrees each time.
- Resume the rate log. If the fast rate survives two proper demagnetizing cycles, it was never magnetism.
What to log
- Rate before demagnetizing
- Number of demagnetizing cycles run
- Rate after each cycle
- Whether the fast rate persisted
Reading your result
| Pattern | What it means |
|---|---|
| Fast rate disappears after demagnetizing | It was magnetism. Free and definitive fix. |
| Fast rate survives two proper demagnetizing cycles | It was never magnetism — something is mechanically wrong. Free, definitive elimination test. |
| Compass deflects the same way regardless of orientation | Plain ferrous attraction, not evidence of magnetization — a false positive. |
| Compass deflection reverses when the watch is rotated 180 degrees | Suggests a genuine magnetic moment, though this refinement is our own synthesis, not a published protocol. |
Related
Run the symptom checker for a verdict on your exact watch.
The Movement Clinic is an independent publication by Timekeeper PH. It is not affiliated with, endorsed by, or connected to Tudor or the Rolex Group. This self-test is general guidance, not a substitute for a qualified watchmaker.