I did once adjust a cheap Invicta diver that my stepson had, purely to see if it could be done. I didn't have a timegrapher and just (very lightly) touched the lever arm, as it didn't have an adjustment screw, and then left it overnight. It worked, but I'm sure would have been a lot easier with a timegrapher!JAFO wrote: ↑Fri Feb 12, 2021 2:58 pmI assume the advance/retard is accessible? Can someone advise how much you need to adjust the advance/retard. Is it an imperceptible fraction, or is it a little bit more than that. Can you do it while the watch is running? I've certainly played around with a carriage clock without seemingly making much difference. I just tend to re-adjust the clock it once a week. It's certainly easier, as you don't have to take the back off.
It found it did indeed just take an almost imperceptible movement either way to make a sizeable change