Expert: William J Perkins - 2/6/2008

Question
I HAVE A TREND WITH A 109 MOVEMENT STYLE: 851W-829 PAC: O79  WHILE PULLING THE CHAIN WE THOUGHT IT MAY HAVE GONE UP TO FAR AND HUNG IT UP. IT DOESN'T APPEAR SO BUT STRIKE DOESN'T RING CONSISTENTLY UNLESS I SLID THE THE ON OFF (CHIME)AT TOP OF HOUR . THERE IS A STAR LIKE GEAR ON BACK FACE OF WHEEL TRAIN IS THIS A ADJUSTMENT TO TRIM HOW FAR THE CHAIN CAN BE PULLED UP ? SO AS NOT TO CRASH INTO THE  WORKS. ANY HELP OR DIRECTIVE WOULD BE APPRECIATED

Answer
Of all the special features clock manufacturers have placed on their movements the stopworks is the least understood. Should this mechanism be disturbed, uninformed clockmakers would be well advised to remove the components, rather than try to "bull" it through.  I suspect you might be the recipient of ill advised tinkering resulting in improper winding, the very thing the feature was designed to prevent.  I can, possibly, walk you through a corrective procedure.  To do so I would need more information.  First provide me with all the information stamped upon your clock movements backplate.  Secondly clear pictures of your movements stopworks.  With these I could, identify the precise movement involved and secondly the form of the stopworks.  Send such information to my personal e-mail address, <flashpowder@hotmail.com>  use stopworks as subject.  Regards WJP