Initial Slowness Mystery

[Ethan Lipsig]

I just got two pocket watches back from one of the highly respected professional watchmakers I use, who had COA'd them. One watch, a V&C, is keeping time highly accurately. The other watch, a Cartier, is behaving very strangely, although my watchmaker said it was working perfectly for him before he sent it back to me. He's asked me to return it to him, which I will do, but I am really curious as to why the watch is misbehaving.

The Cartier loses about 4 minutes within an hour of first fully winding it and setting the time. Then it starts to lose time more slowly, losing another 4 minutes over the next 2-4 hours. Then it stops losing time and runs 8 minutes slow for another 24 hours. This occurs when I run the Cartier dial up or dial down. What would cause such misbehavior?

My watchmaker thought that the watch might have gotten magnetized in transit to me, even though the V&C was in the same shipment and is running fine. My watchmaker asked me to use my demagnetizer to demagnetize the Cartier, which I did. The de-accelerating slowness I described in the preceding paragraph reflects performance after I demagnetized the watch. I think it had been running even more slowly before then, but I didn't keep records of that.

 

[John Runciman]

I don't suppose you have a timing machine? This way we can separate timing issues from mechanical issues.

Than the magnetism issue? It probably depends upon a whole bunch of things like how big was the box how close was one watch to whatever the magnetic source was if there was a magnetic source. Then of course the hairsprings are they both identical? Too many factors to arbitrarily rule out anything on that. Especially considering all of the equipment used to move packages that have magnetic fields.

 

[Ethan Lipsig]

John, I have zero watchmaking skills and equipment (except for my demagnetizer). I don't have a timing machine. I just find it so curious that the Cartier runs very slow at first and that gradually speeds up so that it stops losing time after about four hours, during which it lost about eight minutes.

 

[DeweyC]

I just got two pocket watches back from one of the highly respected professional watchmakers I use, who had COA'd them. One watch, a V&C, is keeping time highly accurately. The other watch, a Cartier, is behaving very strangely, although my watchmaker said it was working perfectly for him before he sent it back to me. He's asked me to return it to him, which I will do, but I am really curious as to why the watch is misbehaving.

The Cartier loses about 4 minutes within an hour of first fully winding it and setting the time. Then it starts to lose time more slowly, losing another 4 minutes over the next 2-4 hours. Then it stops losing time and runs 8 minutes slow for another 24 hours. This occurs when I run the Cartier dial up or dial down. What would cause such misbehavior?

My watchmaker thought that the watch might have gotten magnetized in transit to me, even though the V&C was in the same shipment and is running fine. My watchmaker asked me to use my demagnetizer to demagnetize the Cartier, which I did. The de-accelerating slowness I described in the preceding paragraph reflects performance after I demagnetized the watch. I think it had been running even more slowly before then, but I didn't keep records of that.

Ethan,

This sounds like a mechanical fault rather than one resulting from environmental influences. Given you leave the mechanics to your watchmaker, I doubt you have the desire to open the watch and check the balance motion. And it is often hard for owners to know what good amplitude looks like anyway.

But I suspect there is a fault interfering with power transmission that varies with the train. Could be anything from a popped mainspring barrel cap to the hour hand hub rubbing on the dial. Just gotta send it back to see what is.

Happens to all of us.

 

[Ethan Lipsig]

Dewey, I think I know what good amplitude looks like. If I do, the Cartier's got it.

 

[DeweyC]

Hmmm. I am at a loss then. External influences typically would not be so systematic. Keep us updated.

 

[DeweyC]

Just a follow up. Did this ever get resolved?

 

[Ethan Lipsig]

Not yet. The watchmaker who serviced the watch has asked me to return it to him as soon as he finishes working on another batch of my watches. He swears that the Cartier was working perfectly when he sent it back to me after servicing it.

 

[pocketsrforwatches]

A slightly loose canon pinion can cause what you describe. I have had this happen in almost exactly the same way.

Roger

 

[pocketsrforwatches]

Any update on the resolution to this problem?

 

[Ethan Lipsig]

Any update on the resolution to this problem?

Not yet.

 

[SpringDriven]

Setting the time would indicate if the cannon pinion is loose, based on how it feels setting the time through the crown.

The minute hand could be dragging on the crystal, perhaps. If the drag is significant enough the watch can continue running while the cannon pinion slips a bit from the resistance.

Just speculation.