Over the past decade we have found that more and more watches come back to us
with the following issues:
Running fast
Running slow
Stopping intermittently
While this can sometimes be an issue with the watch in 90% of cases, the watch has become magnetised. We believe this is caused by the digital age mobile phones, tablets and PC's, If you are like me, you may use your iPad as a tray when moving from room to room, beware if you place a watch on your ipad as it will become magnetised, Mobile phones are equally good magnets, Put your watch on your phone or in your pocket with your phone and it will become magnetised, Laptops and PC's have also great magnets, Loudspeakers for your TV surround sound system - while these are often shielded, they still produce a field strong enough to magnetise your watch.
Below shows the effect of some of these devices on a navigation compass.
The reason magnetic fields and magnetisation of watches causes such a problem is down to the balance spring. Once it becomes magnetic even slightly, it can become distorted. The coils of the spring can stick to each other or pull against the natural movement and this has an effect on the amplitude of the balance swing causing the above symptoms.
If you are experiencing any of the above issues, you can easily check with a cheap navigation compass holding it close to the balance. You will see the needle oscillate with the balance.
Demagnetising is a quick and simple process, if you have the correct equipment. There are some cheap demagnetisers on the market, but these unfortunately are poorly constructed. They use one side of a transformer leaving the other side unconnected, to produce a field this which is not precise and needs trial and error to find the sweet spot - by this time your demagnetiser is very hot and may begin to melt as they can only be run for a few seconds at a time.
There are some very good demagnetisers out there, but be prepared to spend upwards of £200.
Written by David Panunzio @romandial.com
October, 2017.