Felsa 4007n

[chadders1966]

Hi

I've got a nice Allaine watch with a Felsa 4007n movement. The watch runs well in 4 positions, amplitude a bit low so I'm checking the train and mainspring, but beat error is 0.2 or less and time consistent  within a couple secs -/+. However to achieve this the regulator is completely over on the + side - hopefully you can see on the photos. What would cause this, incorrect replacement haispring perhaps? As I said it does run well and consistently, but I like to do as good a job as I can and this doesn't look right. Thanks

Stephen

 

[rogart63]

When i look at similar movement on google they almost all have the arm there? So that is  probably okay? 

[DouglasSkinner]

I'm a relative newbee but it seems to me that the main point is error and power reserve.  If a watch is maintaining small positional errors and has a good power reserve, then I don't worry about amplitude.  If it runs good, it runs good!

[chadders1966]

I would think it a bit strange if the regulator is meant to be in that position. It makes a very large gap between the stud and regulator pins, and also would mean the timing is only adjustable to make the watch run slower.

[rogart63]

Have you tested to move the beat error arm all the way to the other side? 

Sometimes i could find a good beaterror on two positions?

Either that or the hairspring is in the wrong position? 

[chadders1966]

Yes, I tried that, it just loses time and then goes completely haywire. What's puzzling is the fact that it is working perfectly when the regulator is adjusted to this extreme position. That's why I wondered if it could have had the hairspring replaced, but I don't know if a watch would work that well if that was the case.

[Steve21185]

From the second photo, it looks as if the hairspring's out of shape. The terminal curve looks all wrong, and the gaps between the coils look are uneven.  If so, I'd be more than happy if the watch is running well in any position...

I re-built a 4007N in a MuDu a little while ago, one of my first attempts. Looking back at photos of the completed movement, the regulator was in pretty much the same place as yours but the regulator pins were only about halfway along the terminal curve. I think maybe your hairspring is wrong/damaged, but I'm just a beginner so let's wait for some second opinions..!

[StuartBaker104]

It looks to me that the regulator pins sit mid-way between the stud carrier and the balance cock, so you have a good range of adjustment.

However, other pictures I've seen on t'internet show the stud carrier on top of the regulator arm.

Here's a nice picture http://forums.timezone.com/index.php?t=msg&th=1745735&rid=0

 

[chadders1966]

Thanks for all the suggestions. I've now put a new mainspring in and the amplitude is much improved, all readings are great. There is something not quite right with it, but as it's working so well I'm just going to leave it alone for now.