The movement in its initial disassembly.
Checking the truth of wheel train. The watch has a transfer of energy problem
A previous attempt at tightening the mainspring arbor holes.
Detail where a previous watchmaker made a series of punches to close the hole.
Here you can see the mainspring barrel is running out of truth, see space between top of barrel and main plate.
Here it is almost closed, out of truth by about .5mm.
Another sign of barrel 'wobbling', it scraped against the center wheel.
Checking on lathe, the mainspring wobbles and is out of truth.
Arbor is OK, so it is a problem of the mainspring barrel.
Center wheel runs true.
The arbor seat is faulty due to strength of mainspring. About .10mm is shaved off on barrel cap.
Same is done to arbor seat on mainspring barrel body.
The mainspring barrel and cap with refinished arbor seat.
Runs true now.
Mainspring power flows well now and the watch, after an initial cleaning, runs fairly well.