any advice about this problem.

[Mary Watch 205]

Any memeber saw this problem before? I didn't see this before, so don't know what problem it is.  

any advice is helpfull,  Thank you.  

https://m.imgur.com/a/HBbgPvn

[GingerApple 7,291]

Possibly the minute hand is just a bit loose where it attaches to the pinion?

@GenTLe will know more than me.

EVERYONE will know more than me.

[GenTLe 1,509]

2 hours ago, Mary Watch said:

Any memeber saw this problem before? I didn't see this before, so don't know what problem it is.  

any advice is helpfull,  Thank you.  

https://m.imgur.com/a/HBbgPvn

Hi Mary, please explain as I can't see what you are referring to from the video...

[GingerApple 7,291]

17 minutes ago, GenTLe said:

Hi Mary, please explain as I can't see what you are referring to from the video...

The minute hand slips as the person taps the watch.

[Aramis2288 6,269]

17 minutes ago, GenTLe said:

Hi Mary, please explain as I can't see what you are referring to from the video...

I think what Mary is referring to is the fact that despite the winded watch (judging by the moving red seconds hand at 9) the minutes hand (being around 27th min past a full hour at the beginning of the video) is moving towards 30th min when the watch is turned to the side and tapped onto. In the same way, when the guy turns it 180 degrees and starts tapping again, the minutes hand seems to be returning into its original position - 27th minute.

[GenTLe 1,509]

Oh... Oh... Ok.

I was focusing on the hour hand...

Ok, so the 7750 transmits the movement from the main gear train to the hands in a way which is much more indirect than let's say a 2824.

The center wheel (below the main plate) is fitted (on the dial side of the main plate) to a friction wheel (nr.1 in the picture), this one moves the intermediate wheel number 2 which moves both the minute and hour hands cannon pinions, nr. 3 (the minute hand cannon pinion is sitting below the big hour cannon pinion).

This is the clutch (driving pinion) nr.1 seen from upside down and greased:

Because of this indirect motion transmission, on 7750s there is normally 1 min play of the minute hand, and you can well see this when the watch is in time-setting position, and it's normal for the 7750s: you have 1min play, when setting the time, before starting to feel the resistance of the clutch nr.1 in the picture.

I think it's the same effect you see there. On properly lubricated movements this doesn't happen (by "tapping on the watch"), or happens less, just because there is a bit of grease between the minute hand cannon pinion and the post on which it sits. That grease does enough friction to prevent the hand to move.

And, still, if you don't "tap on the watch" (which you shouldn't do anyway) the hand shouldn't move, as when the movement is running it is kept in constant advancement motion. Of course the effect is more visible on watches with big minute hands like the IWCs.

I'd say if the movement of the hand is limited to 1 minute, that's pretty normal for unserviced 7750 with heavy minute hand.

If the movement of the hand is more than 1 minute (like 5 minutes or so) then either the clutch wheel nr.3 is not properly fitted on the center wheel pinion, or it's faulty, or simply the hand is loose on its cannon pinion.

Tell to the guy that if he is so afflicted by that, I'll take that watch (for free as I've plenty of IWCs already), service it... And of course keep it

Edited April 20, 2021 by GenTLe

[GingerApple 7,291]

The man knows his shit!

5 minutes ago, GenTLe said:

or simply the hand is loose on its cannon pinion.

Though note, I could be right. #motherfuckinggingerlegend

[GenTLe 1,509]

2 minutes ago, TheGingerFerret said:

The man knows his shit!

Though note, I could be right. #motherfuckinggingerlegend

Not this time  If it was loose, then it would have moved to vertical position at 1st tap or even simply rotating the watch 

[FunnyStarSystem 7,538]

I have this issue on the same rep. The most annoying aspect is when you go to set the time you can never tell when the gear will pick up and the minute hand will start to move, so setting it accurately is nearly impossible - but perhaps I'm asking too much

Thank you for the explanation @GenTLe

[GenTLe 1,509]

1 minute ago, FunnyStarSystem said:

I have this issue on the same rep. The most annoying aspect is when you go to set the time you can never tell when the gear will pick up and the minute hand will start to move, so setting it accurately is nearly impossible - but perhaps I'm asking too much

Just advance time more and than set it going back, that way you should eliminate the slack. Doesn't matter if when you press back the crown the hand moves a bit forward, it will stay stand still until the play between those 3 gears goes to zero and that is when you have set your time with the crown.

[FunnyStarSystem 7,538]

1 hour ago, GenTLe said:

Just advance time more and than set it going back, that way you should eliminate the slack. Doesn't matter if when you press back the crown the hand moves a bit forward, it will stay stand still until the play between those 3 gears goes to zero and that is when you have set your time with the crown.

Meh, it must suffer from a more advanced condtition because no matter how you try to set it (including your advice above) anywhere from 30 seconds to a full minute + will pass before it catches and moves. I've owned it for years and tried different methods, if it was a predictable amount it wouldn't matter, but it varies how long it waits to engage so you just have to go with it. I own the gen now so not too concerned anymore, happily it does not have this issue.

The chrono also stopped zeroing at some point - even though I didn't mean to engage it knowing what could happen, it got pushed accidentally. But to avoid opening it and taking out the movement to manually zero the main chrono and subdials, I ran it 12 some odd hours until it came exactly into position and then stopped the chrono precisely. So it's just waiting for me to accidentally hit the top button again to keep going   NIce rep in every way except the movement is total shite!

[als86 5,283]

Thank you @GenTLe a very thorough explanation  for the inexperienced !

[GingerApple 7,291]

27 minutes ago, FunnyStarSystem said:

I own the gen now 

I OWN THE GEN DON'T YOU KNOW!!!! GET ME!!!!

[FunnyStarSystem 7,538]

Just now, TheGingerFerret said:

I OWN THE GEN DON'T YOU KNOW!!!! GET ME!!!!

[Mary Watch 205]

Thank you so much.   

[deju 1,878]

16 hours ago, TheGingerFerret said:

I OWN THE GEN DON'T YOU KNOW!!!! GET ME!!!!

Gen wanker alert!!!!!