Depends if I could catch it ? :)
Sorry, gaining minutes rather than seconds per day.
How fast would a watch be running for you to consider demagnetising it?
Depends if I could catch it ? :)
Sorry, gaining minutes rather than seconds per day.
It doesn't have to be running fast at all. I demag all incoming watches to make sure I'm getting their true readings, for instance.
Here I demagnetising a Omega watch with a great result.
https://youtu.be/P8SV7Ogl2Aw
Recently noticed that my previously very accurate (+/- 5sec a day) Speedbird GMT was gaining 30-40 seconds a day. Having handled some very strong magnets at work I thought I'd dig out my cheap Anchor demagnetiser and give it a go. Instantly back to -6 sec/day on the timegrapher.
So, to answer the original question, about 30 seconds faster was enough for me to give it a go.