Crown
The external knob on the side of the case used for winding the mainspring and setting the time.
What is the Crown?
The crown is the small knurled knob you see on the side of a watch case — almost always at the 3 o'clock position. It serves as the primary external control for a mechanical watch, connecting through a tube in the case to the winding stem inside the movement.
Crown Positions
Most crowns have two or three positions:
- Position 0 (pushed in, screwed down) — normal wearing position; on screw-down crowns this also seals the case against water
- Position 1 (pulled out one click) — on watches with a date, this typically allows the date to be quickly set
- Position 2 (pulled out fully) — sets the time; on manual-wind movements, this position also stops the balance wheel (called "hacking") so you can set the seconds precisely
Screw-Down Crowns
Many dive watches and sport watches use a screw-down crown, which threads into the case tube to form a watertight seal. These must be fully unscrewed before any setting or winding can be done, and screwed back down firmly before the watch is exposed to water. A damaged or improperly closed screw-down crown is one of the most common causes of water damage in dive watches.
Crown Servicing
During a service, the crown and stem are inspected for wear and the crown tube gasket (O-ring) is replaced. On water-resistant watches, pressure testing is performed after reassembly to verify the seal integrity.