Rolex Crown Single/Multi-start Thread?

[MoQa BianQa]

Hello,

Been recently reading into fastener threads and learned that single start-threads and multi-start threads each have their own pros/cons. Often times screw-down mechanisms such as a water bottle cap utilizes multi-start threads to reduce the number of turns and increase water-resistance.

This got me curious, does anyone know if Rolex double-lock/trip-lock crowns use multi-start threads? If so that might be noticed when the crown is fully screwed down - can land on different positions. I've noticed my old Date-just crown landing on two different positions when fully screwed, however this also may be possible because the crown threads have been stripped (it's a very old watch that has yet to be serviced).

*can't post photo explanation yet cause my post count is still below 10. So please Google.

[Tools]

Rolex uses single point threads on the tube and crown.

It takes ~1 1/2 turns to screw down a crown. With a double entry thread that would be halved, but you would still have only two possible landing positions and it would be quite easy to unscrew that, now only 3/4 turn, crown. Even a 4 entry thread, which would be about a quarter turn to screw down, or off, wouldn't always align as you might think. With folks who measure the rehaut crown distances by the width of a piece of paper thickness, you would still end up with the "my crown doesn't align" for even a slightly cocked crown. Or they would complain that they need to screw it down several times to find that magic entry thread.

Anybody can attach an image, as long as it meets the size requirements