Component record · Keyless work
Winding Stem Square
Partially verifiedThe squared section of the stem engaging the clutch wheel.
What it does
Transmits crown rotation to the keyless work.
How it works
The square section lets the clutch wheel slide along the stem while still transmitting torque.
Evolution
Dimensions are calibre-specific, so stems are not generally interchangeable.
Known variations
- Integral stem
- Two-part split stem
Identification for collectors
- A worn square makes the crown turn without winding.
Common failure modes
- Rounded square
- Bent or broken stem at the thread
Related photographs



No confidently matched photograph of this subject has been found yet. These photographs show a closely related record, and are not examples of the type described on this page.
Sources & references
- de Carle, D., Practical Watch Repairing
- de Carle, D., Watch and Clock Encyclopedia
- Daniels, G., Watchmaking
Where sources disagree, the disagreement is stated rather than resolved silently.