The Movement Clinic · Self-test
How to test your watch's positional variation
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
Positions are named for where the crown points: dial-up, dial-down, crown-down, crown-up, crown-left, crown-right. Tudor's published rate spec is a mean across positions — a fixed daily habit, such as leaving the watch crown-up every night, will never show you that mean.
The steps
- Hand-wind the watch fully.
- Run it 24 hours in one position, rewind to full, then repeat for each of the six positions over six days.
- Repeat the first position again on day 7 to confirm the reading is repeatable.
- Compute the mean rate, the delta (max minus min), the horizontal mean, the vertical mean, and horizontal-minus-vertical.
What to log
- Position tested each day
- Rate recorded for that position
- Wind state before each 24-hour run
- Running mean, delta, horizontal mean, vertical mean
Reading your result
| Pattern | What it means |
|---|---|
| Delta under about 10 s/d | Good; under 5 s/d is excellent. COSC's own limits: horizontal-vs-vertical difference −6/+8 s/d, largest variation from mean ≤10 s/d. |
| Delta over 15-20 s/d | Worn or dirty balance pivots, dry jewels, poise error, or a hairspring problem. |
| All vertical positions much slower than horizontal | Classic low-amplitude signature: dry pivots or a weak mainspring. |
| Dial-up and dial-down differ more than 8-10 s/d from each other | A pivot or cap-jewel problem on one side, endshake, a bent pivot, or a hairspring rubbing. |
| Opposing verticals (crown-up vs crown-down) differ | Poise error — the balance's centre of mass is off-centre. |
| Rate wanders within one position across repeated runs | Intermittent cause: debris, a hairspring touching, or a magnetized component. |
| Delta was small a year ago and is large now | Lubricant degradation. Trend beats absolute value. |
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.