The Gravity of the Village Clock

Some time ago I made mention of getting involved with the running of the village clock.   There was an added incentive as this was a Cooke of York movement dating back to 1869.  Anything associated with the  City of York is always of high interest as it was my birth place.  That is except the soccer team but I try not to get drawn into that discussion.

Back to the clock.  Myself and a colleague in the village have been working on the clock to bring it back to time.  We were getting pretty close.   Then it stopped.   Despite a few restarts it refused to run for any length of time.

We rolled up our sleeves and gave it a thorough visual inspection.   We were just about to leave it for the day when we spotted that the pins on the pin wheel on the gravity escapement arbor seemed very tight to the arbor supporting bracket.   Closer inspection revealed one pin of the five seemed to be slightly at an angle.  Even closer inspection showed a visible witness mark on the bracket where the pin or pins were rubbing on the bracket.   There was no mechanism to centre the arbor away from the bracket.   

We decided to remove the arbor complete with pin wheel, fly etc.   This was fairly straightforward.  A single screw at the opposite end to the escapement arms could be unfastened and the arbour came free.  Except it wasn’t that easy to unscrew as the screwdriver slot was very narrow.

Having got the arbor assembly back to my workshop I discovered two of the pins were lose, one of them to the point of falling out.   It seemed to have been held in place from coming out any further by the support bracket.   

I marked and numbered the escapement legs and removed each pin in turn, shortened each by 0.5mm, degreased the threads on each pin and its associated mounting hole and then refitted each one with a dab of Loctite to hold them in place. 

Spinning the arbor in my hand I could now see that all pins looked parallel and the length was much more consistent.  Hopefully the pins will now comfortably clear the mounting bracket.

The gravity escapement arbor showing the five escapement legs and the five pins that needed shortening

To make refitting easier I made a small hand tool to fit the slot on the mounting screw and used a hacksaw blade as a pseudo screwdriver blade to more easily turn and tighten the screw.

Since refitting the arbor the clock was running slightly slowly so we removed a penny from the weight tray and it now seems pretty much spot on.

Similar or related subjects : –