Love story with a JF A7750 seconds at six

[BestReplicaHunter]

Hi,

Yes, we all know the A7750 seconds at six is a problematic movement. But the JF Daytona is so sexy...
I thought... What the hack (no pun intended), let's get one!

Got it.

Worked perfectly out of the box other than a jumpy seconds hand at six. After a few days it stopped.
Took it to a local watchsmith that told me the balance wheel is probably bad. He removed the balance wheel and re-inserted it.
Watch worked again but stopped several days after (on the wrist, manual winding no-go).

It's all part of the rep game, right?

Since I quickly fell in love with my now non-working Daytona, I've ordered another one.

Arrived DOA.

Took it to my local watchsmith again. "Balance wheel" he said.

So I took the balance wheel off a 2 years old (and still running great!) V6 HBB A7750 and inserted it to my JF Daytona.

It runs!! Then stops.

So what I have now is a watch that:

1. Is equipped with a balance wheel from a watch which always worked, so it's not the problem.
2. Manually rotating/touching the escapement wheel a little makes the watch run again for a few hours(!) then stops (on the wrist).
3. Manual winding no-go. So it's not a rotor problem.
4. When it stops, the seconds hand seems to always stops in the same position.


Any idea what could be the problem?

 

[KBH]

The only problem is that it's a seconds at six movement. It's the gear module that changes the location of the second hand creates too much friction. It's a well known and well documented problem. Several points immediately come to mind.

1. Have you read at all about the sec @ 6 Daytona and all it's problems?

2. I think maybe your watch maker isn't best quality.

3. Why not send at least the first defective one back to your TD, if not both of them. Although I'm not sure how he'll feel about having someone swapping out balance wheels and then taking over the warranty.

4. Most of the forum watch smiths won't work on those movements. Maybe Domi in the EU but not sure about that.

Other than that, the best I can do is say best of luck with your problem. Hope someone can fix you up with some help.

 

[BestReplicaHunter]

I've also had a ROO where the hands fell off , a Diver with a broken keyless (without ever removing the stem or opening the case) a sub with a "Swiss" movement with slipping crown... So .... It's all part of this hobby

My Watchsmith isnt the best but it's very hard to service watches outside ADs where I live...

And I try not to ship watches back to China if possible...

 

[BestReplicaHunter]

Any ideas what could be wrong from one of the movement experts here? I know it's hard to tell without actually servicing the watch, but ideas would be appropriated...

Maybe this could help point my Watchsmith in the right direction...

 

[dino69]

I get the same problem with my AP ROO FC 44 JF seconds at 12.
Looks like a rotor problem....the self-winding is not working.....I make a hand wound at the beginning...and few days after the movement stops. The self-winding with the rotor is not working.