Crown disengagement winding question.

[RPierce84]

I've got a few reps now (half a dozen) and only one of them disengages the winding mechanism when the crown is pushed in to screw it in place. Is there a common issue as to why one would disengage and the others do not? 5 or the 6 have 2824 movements, the other is a 7750. One of the 2824 is the one that actually disengages, the rest do not.

Assuming they should disengage, what can I look for as to why the others do not?

 

[Plaasbaas]

From my understanding it has to do with a spring loaded crown, that disengages inside the crown itself once you push it in, but I could be wrong, sorry.

 

[mclarendude]

It's not the movement that disengages, it's the crown.

When you push the crown in, what should turn is only the crown and the stem remains stagnant.

This happens since in the crown post, there is a spring inside the post that causes a telescopic movement (or ability rather) that allows the stem to remain at a constant length while the crown itself screws onto the crown thread tube.

This is honestly normal and does not hurt the movement.

 

[Karbon74]

I learned that lesson the hard way when I broke a stem and messed up the keyless works, trying to "fix" a perfectly working watch.

If the watch works, don't sweat the little things...because if (like me) you don't know what you are doing, the small things become big things

 

[RPierce84]

It's not the movement that disengages, it's the crown.

When you push the crown in, what should turn is only the crown and the stem remains stagnant.

This happens since in the crown post, there is a spring inside the post that causes a telescopic movement (or ability rather) that allows the stem to remain at a constant length while the crown itself screws onto the crown thread tube.

This is honestly normal and does not hurt the movement.

I know it seems to be normal and won't harm the movement, I just don't like it . Haha. So it's likely that the stem has been trimmed too short then and just isn't disengaging the crown? Is is the crown tube the one responsible for disengaging the crown when you push it in?

 

[shinynewbling25]

Thanks mclarendude. Didn't know this. I totally destroyed a crown like the one appearing in the middle. The stem broke off and I thought that little hexagonal part was still the stem and was using pliers to try to get it out. I mangled it badly.

 

[RPierce84]

I learned that lesson the hard way when I broke a stem and messed up the keyless works, trying to "fix" a perfectly working watch.

If the watch works, don't sweat the little things...because if (like me) you don't know what you are doing, the small things become big things

I'm 100% guilty of this. Luckily I'm fairly mechanically inclined and have done some minor watch fixing/regulating on my reps. Just haven't figured this out yet

 

[mclarendude]

I know it seems to be normal and won't harm the movement, I just don't like it . Haha. So it's likely that the stem has been trimmed too short then and just isn't disengaging the crown? Is is the crown tube the one responsible for disengaging the crown when you push it in?

No, the stem is fine if you have no issue cycling through positions (winding, date change, time setting and viceversa).

The only indication the stem is the issue is if you try to push in the crown after setting the time or date and it won't return to winding position, no matter how hard you push in.

The crown tube has only one purpose, which is to provide a thread to the thread inside the crown and mesh.

The "problem" here would like inside the crown post (where the stem is screwed into). It could be that the spring is dirty, or just it is a different design of crown post.

Honestly nothing worth investing in since you cannot just break into the post and fix it. You'd need a new crown and the possibility is huge that a new crown would act the same if they share the same post design.

 

[mclarendude]

If anything, if you take the crown and stem off the watch, you could push down very gently on the crown post to make the post retract and maybe instill a small drop of grease or lube, that could help. But I think it would be futile.

 

[RPierce84]

No, the stem is fine if you have no issue cycling through positions (winding, date change, time setting and viceversa).

The only indication the stem is the issue is if you try to push in the crown after setting the time or date and it won't return to winding position, no matter how hard you push in.

The crown tube has only one purpose, which is to provide a thread to the thread inside the crown and mesh.

The "problem" here would like inside the crown post (where the stem is screwed into). It could be that the spring is dirty, or just it is a different design of crown post.

Honestly nothing worth investing in since you cannot just break into the post and fix it. You'd need a new crown and the possibility is huge that a new crown would act the same if they share the same post design.

Copy that! Thanks so much for explaining!

 

[mclarendude]

Copy that! Thanks so much for explaining!

I applaud your technical curiosity.