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Loosing time when crown up


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Hi 

I just serviced a watch with a good amplitude and time when face up and down (250-270 and +-5 sec) but when crown up, the amplitude falls down and time as well. What can be the reason? Any scenarios? 

 

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The good thing is your vertical positions are all roughly similar, and the horizontal positions roughly similar. Did you measure before servicing?

I would let the watch run for 24hr, then fully wind and then measure again. I have observed lower amplitudes just after servicing, which increase after 24hr of running. May be the lubricants haven’t fully distributed properly because my oiling techniques aren’t optimal yet etc.

If this doesn’t help you have to manually check all pivots, free running of wheels, end shakes etc. Lower amplitudes in vertical positions are normal due to higher friction between pivots and jewels, but the amplitude shouldn’t be that different from the horizontal. Vertical positions tend to have more friction because the pivots of the wheels have to rest on both jewels, while the horizontal positions is mainly only one jewel, depending on face up or down.

Also, I would demagnetize the movement just to be safe, and lower the beat error to below 0.5ms if possible.

Edited by ifibrin
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I can't remember the results prior to service. I have de-magnetised the watch and the pivots are not broken either. But what I wonder is that the wheel tilts when diassembled and laying upside down on the table. 

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9 hours ago, Khan said:

I can't remember the results prior to service. I have de-magnetised the watch and the pivots are not broken either. But what I wonder is that the wheel tilts when diassembled and laying upside down on the table. 

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If the balance wheel tilts when upside down, and the balance wheel pivot is located in the hole jewel, it COULD mean that the hairspring isn’t flat. This MAY potentially affect the amplitude of the watch in the vertical positions.

But getting the hairspring flat could also introduce a lot of other problems and is not meant for beginners. I would recommend you look into other potential issues before even thinking about this.

I didn’t mean that the pivots were broken causing the lower amplitudes in vertical positions. Since the shoulders of the train wheel pivots rest on the upper and lower jewels in the vertical positions, the increased friction in the vertical positions cause lower amplitude. If the increase in friction is too much, such as due to insufficient end shake, or pivots not polished, the amplitude drop would be larger. But such adjustments would require expensive tools to fix, and special care to diagnose.

When you install everything except the pallet fork and balance cock, and try winding the watch, all the train wheels should spin. Does the escape wheel spin change direction of spin at the last moment? This can be a good indication of train wheel freedom, since it means that all the wheels have very little friction. This is known as back spin, but not all movements may show it.

Have you tried timing the watch again after 24hr at full wind? Is there any difference? How did you lubricate the pallet fork? I hope you didn’t lubricate the pallet fork pivots.

Edited by ifibrin
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A long time ago, I experienced something similar to this problem.

To cut a long story short, I discovered that, after servicing, I had inadvertently put the upper balance jewel back in, upside down.

After this was corrected, the watch (And I) were much happier.

It's just a suggestion.

 

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Above,  Ifibrin has well explained most every significant point . What you can do at this point, is to clean and PEG the escapement as best as you can and adjust the end shakes, you should see better amplitude in vertical positions as a result .

If you have high magnification checking pivots and jewels is a good idea and might reveal excessive wear ...etc. 

Godd luck

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