Watch winding knob in screw-down style for water resistance or push-pull style for easy time adjustment, controlling setting functions.
Screw-down crowns thread into the case creating a water-tight seal, essential for dive watches and sports watches needing high water resistance. Push-pull crowns simply pull out to set time and push back in—easier to operate but less water-resistant, suitable for dress watches.
Initial stiffness is normal in new watches or after servicing. However, excessive resistance may indicate dried lubricants, debris in the crown tube, or damaged crown threads. Never force it—have a watchmaker inspect to prevent damage to the winding mechanism.
No, the case tube threading and crown tube are different designs. Conversion requires complete case modification or replacement. Additionally, gasket placement and water resistance ratings depend on the original design. It's not a simple aftermarket upgrade.