Problem with Hour & Min hands

[Asheron82]

Hey guys, one of my watches that runs on an A7750 is having some problems, the symptoms are that the sec hand still moves while the hour and min hands doesn't are behind time even after setting the correct timing. this only happened after the watch had a brief knock against my bedroom's wooden door.

initially i thought it was a PR issue but putting it on the winder didn't solve either. i set the timing and place it on the winder, the following morning the hour and min hands would not be the same as it should be but late by a few hours/mins.

anyone knows what could be the problem and if this is this an easy fix?

Ash

 

[pf83]

So you're saying the second hand is taking 60 seconds to do a rotation, so the watch isn't running slow, just the main hands?

When you try to set the time does it seem easier to spin the hands than it did before?

If both of those are true, then your cannon pinion has loosened. It is an easy fix for someone who knows how to disassemble a 7750, and has the cannon pinion crimping tool (or who knows how to make one out of some old pliers laying around). Most likely with the movement so far disassembled, a service would be performed as well. The A7750 usually comes out of the box requiring a service. Unless there are some weird complications added to the movement (seconds @12, etc) I would take this opportunity to locate a cheap Swiss 7750 and fit that instead, being extremely careful with the super fragile rep sub dial hands that tend to separate post from hand when you breathe on them.

 

[Asheron82]

yup, the sec hands runs fine as it should however the main hands (hour/min) is slow. for example when i left the watch as it is on the winder at 10pm where the time was correctly set, right now watch hands shows its 3pm but its infact 10am now.

the watch was serviced previously by a watchsmith, as for the adjustment of hands being looser, i cant really tell as i've never had the need too because watch was on the winder when not in use to keep time.

it sounds like an easy fix based on ya explanation, i would suppose that "knock" must have caused the hands to loosen which indirectly caused the "slippin"?

i'm not that proficient in watch repairs so i guess i probably pass it to my watchsmith to have a look at it. nonetheless, thanks for pf83 for ya advice!

Ash

 

[level z]

+1 pf83 ..good advice

 

[md2020]

Sounds like the cannon pin is not secured all the way or when it hit the ground it loosened the hour hand so it doesn't rotate the way it should. It's a relatively easy fix. I've fix these kinds of problems many times. If your going to do it your self first check the hands if there placed firmly on the cannon, if there not secure them on. If that doesn't work you'll have to take off the dial and look under the hood. Let me know if you any questions or need help. :thumbup:

You break'em I Fix'em

 

[Woldemar]

Sounds like the cannon pin is not secured all the way or when it hit the ground it loosened the hour hand so it doesn't rotate the way it should. It's a relatively easy fix. I've fix these kinds of problems many times. If your going to do it your self first check the hands if there placed firmly on the cannon, if there not secure them on. If that doesn't work you'll have to take off the dial and look under the hood. Let me know if you any questions or need help. :thumbup:

You break'em I Fix'em

Hi Dearest Md2020,
I've just read your advise about stuck hands on an AP ROO A7750 withs secs @12.
Sorry for disturbing you.
I have an issue with my brand new AP ROO (JF factory) with an A7750 movement.
After 5 days of a perfect working and without any reason the minutes and the hour hand stopped to move.
All other parts seems to work properly: the balance wheel is spinning, seconds on @12 are running good, chronometer is OK, while the minutes and the second hands do not move.
Timegrapher shows +1 s/d and beat error of 0,0ms.
After setting a correct time the hand may move fore some time (it may be 3 hours as well as 20 minutes), then they stop, while the movement (balance wheel an small seconds hand) go on.
The power reserve is very good.
May I ask you what is the problem?
There is no a trusted watchsmith around who knows the A7750 chinese movement with seconds at@12 and the last solution for me would be sending my rep to the TD back in China.
Thank you very much in advance for your precious advice!
Best regards, Woldemar

Sent from the RWI mobile app

 

[d4m.test]

@Woldemar dude, you revived a five year old thread to ask a question of a guy who seems to have been banned for three and a half years. You'd of been better just posting a new thread.

That being said, sounds to me like the same issue as the OP here. Either the hands are not sitting on the cannon pinion correctly, or the pinion is loose. Either way, it needs someone to open it up and have a looksee.

 

[KBH]

Woldemar, you're replying to a 5 year old thread asking a question of a member who was banned.