Possessed Movement...

[jmb]

The movement in my wife's gen Tudor Princess Oysterdate is really acting strange. When she wears it it will run 45 - 60 minutes per day fast. When I put it on the timer at shows less than 10 seconds/day fast! Any ideas other than it probably needs servicing?

[Ronin]

Timer says its ok? All positions? Perhaps the hands them self are slipping, or binding and pulling.

[jmb]

I never thought to check the hands, it is a vintage piece so it is quite possible it's slipping... I had only checked it face-up, told the ol' lady it was running fine and she must have set it wrong. I then set it and 24 hours later it was 40 minutes fast!

[chronoluvvv]

i like the thread's title

[RWG Technical]

If you only checked it dial up, you didn't check if the hairspring is possibly touching itself, or something else...

Try timing it DU, DD, and CD and see what it shows, there is only one reason for it to run fast, that is a hairspring becoming shorter and vibrating faster...

[jmb]

Thanks, Master The Zigmeister, I'll take a look at it Monday and report back.

[jmb]

I'm going to assume something was binding up the hairspring. I put it back on the timer and it showed 4 min/day fast face down so I took most of the movement apart, removed and reinstalled the balance, and after I got it back together it read 8 sec/day fast - I can live with that! I could not see anything "binding" just by looking at it.

I guess it was good that I had to do this as the screws in the auto-wind and train bridges were all lose!

Thanks for the responses!

[RWG Technical]

Interesting outcome...

It may be worth soaking the balance and hairspring in One-Dip for 10 minutes and drying fully, just in case there is some oil on the hairspring. Sometimes these hairsprings fix themselves, especially if the movement is allowed to run down...

[jmb]

I'll have to order some of that. I have ultrasonic cleaner and rinse. The movement (2555) has obvious signs that it has been serviced many, many times over the years and is probably about worn out. :-( I have an ETA 2651, that that shows much less wear, that I might swap into it if the dial feet fit.

On a side note, I just finished my first movement service yesterday (ETA 2824) and it actually runs!! I have popped it into my Air-King franken to test but so far it's keeping excellent time. I'm sure I used too much oil but I was very surprised it even started ticking!

[RWG Technical]

Excellent news indeed.

We have a habit of needing to see the oil we apply, which you can actually see even in very small quantities if you know what to look for, but it's normal to over oil the movement initially. It's running, which is more than a lot of people can say, congratulations on a job well done...

[jmb]

Thanks! Curling the mainspring back into the barrel was actually one of the most difficult parts.