I have an RMS Vienna clock that stops 6 mins to the hour I can't see for the life of me why.
the repeat leaver is tight after so i move the hands a few mins onwards and it will go again
until 6 mins to the hour ??
My first impulse is that the clock is stopping at warn.
It seems the slight additional energy needed to actuate the warn is enough to stop the clock.
My secondary conclusion is that the clock is lacking power.
If you do not know or understand the warn process in a clock movement, it is time you hit the books and discard the advice from UTube videos, etc.
Best of luck with your venture,
Check the pin position on the warn wheel when it stops. If that pin is at the bottom of the wheel at the point where it stops, sometimes the lever tab that stops the train jams on the pin. The wheel may need to be repositioned so the pin is on top. Or… you may be able to correct it by rotating the gathering pallet slightly.
If the situation is close enough that the warn will stop the movement, that movement is in trouble.
No amount of cleaning, oiling and adjusting will give a long term, reliable operating clock.
Once you solve the wear situation and provide sufficient power to the train, you will solve your problems.