Watch only works when the second hand is running

[kronos twin]

Hello all,

I hesitated to put this in general discussion, since it is related to my PAM 212, but since it may prove relevant to some other brand, I started here.

Two days ago, my PAM 212 simply stopped running. The seconds hand wouldn't start up, even after placing it on a winder for several hours. Out of desperation, I activated the chronograph, and there you have it, the watch starts running again. I wore it the whole day to see if it would continue to work, and sure enough it did, and it kept good time. However, once I stopped the chronograph, that was it. No seconds hand running. I could also see through the caseback that nothing was going on back there until the chrono was again activated.

Has anyone had an issue like this? And idea how to resolve it?

[RWG Technical]

There is something wrong with the tilting pinion for the center seconds chrono.

When the chrono is ON, the tilting pinion engages into the center seconds gear and it transfers the running seconds from the basic movement to the chrono. When you press STOP, the tilting pinion is supposed to disengage from the center seconds gear as a brake lever holds the center seconds gear in place. When you RESET the chrono the tilting pinion is supposed to remain disengaged from the center seconds gear becasue the hammer has reset the gear and is holding it in place.

If the watch only runs with the chono on, the problem has to be with the tilting pinion not disengaging, since the center seconds gear is only free to rotate with the chono selected to ON.

You need a watchsmith to inspect the chrono and tilting pinion to see what is going on...

RG

[kronos twin]

There is something wrong with the tilting pinion for the center seconds chrono.

When the chrono is ON, the tilting pinion engages into the center seconds gear and it transfers the running seconds from the basic movement to the chrono. When you press STOP, the tilting pinion is supposed to disengage from the center seconds gear as a brake lever holds the center seconds gear in place. When you RESET the chrono the tilting pinion is supposed to remain disengaged from the center seconds gear becasue the hammer has reset the gear and is holding it in place.

If the watch only runs with the chono on, the problem has to be with the tilting pinion not disengaging, since the center seconds gear is only free to rotate with the chono selected to ON.

You need a watchsmith to inspect the chrono and tilting pinion to see what is going on...

RG

Thanks so much! i will most definitely check with a watchsmith. This helps me a lot. I will report back with anything significant.