Problem with day-date changing on A7750

[yim156]

I just send my watch with A7750 movement for service.

Actually, I got the problem before sending it to the watch-man.

The watch-man told me that he clean all the parts and oil them.

When I took it back, I tested it and it worked.

I just saw that the day changed when it was 11.50 and the date changed at 1.20

I tried it again by changing time to see how the day-date changed and it is the same.

Then, I tried to change day-date. The result was "broken". I can not change day-date any longer!!!

I wonder what is the problem ?????

Well, if I change the day and date wheels, will the problem be solved?

Please help me. (T_T)

BTW, I will contact the watch-man again tomorrow.

Thank you

[Watchmeister]

Sorry to hear it is broken. It will have to be taken apart again. I presume you know that the day always changes before the numerical date. The movement doesn't have enough power and as such is not designed to change them simultaneously. And depending on the age of the movement when the changeover starts and stops for both can be as early as 9 pm (mechanism actually engages at 8 pm) on the start and as late as 3:30 am (mechanism completely disengages around 4 am). If neither change I would guess it is unlikely to simply be a stuck day wheel.

[Pugwash]

I wonder what is the problem ?????

Well, if I change the day and date wheels, will the problem be solved?

Please help me. (T_T)

Did you change the date between 10pm and 2am? If so, this can make the wheels pop out. It's easy to fix once the hands and dial have been removed.

[yim156]

Did you change the date between 10pm and 2am? If so, this can make the wheels pop out. It's easy to fix once the hands and dial have been removed.

Yap, I change date at 1.30pm. So you mean that it is a design of the movement and happen to be like this all the time?

Again last night at 3am, I found out that when I set the time, day/date changed.

Is it because just the wheels pop out and can be fixed by re-align them again?

Nothing broken?

Thank you

[yim156]

I presume you know that the day always changes before the numerical date. The movement doesn't have enough power and as such is not designed to change them simultaneously. And depending on the age of the movement when the changeover starts and stops for both can be as early as 9 pm (mechanism actually engages at 8 pm) on the start and as late as 3:30 am (mechanism completely disengages around 4 am). If neither change I would guess it is unlikely to simply be a stuck day wheel.

hahaha... Sorry, I have never notice about this before.

So the day/date changing mechanism will be taken over the night to change?

Mann, it is my bad.

I love this place!!

Thank you.