Seth Thomas 89 movement with a 4 1/2 inch pendulum

In for repair is a Seth Thomas 89 movement.  Follow this link for a general history of the Seth Thomas Clock Company.  To properly repair this movement requires specialized tools to disassemble, repair bushings, polish pivots, and in this case rebuild a complete pivot.  More on this later.

Here is the movement as it was received:
Front
Back
Notice the bell and strike hammer are missing

The mainsprings were clamped so the power is taken off the gearing.  This is done for easy disassemble and to accurately ascertain the condition of the pivot holes.

Here is a short video showing how much wear was in the pivot holes .

These next two images are again the front and back of the movement.  There are 14 pivot holes that were sloppy and egg shaped that are in need of repair (bushings).  The holes have been marked with a RED marker.


Diagnosing a repair with the movement together shows almost everything that could be wrong with the clock.  Every once in a while, a discovery is made that is not expected.  Here is the time side 3rd wheel pivot.  Not good!  Notice the significant wear on the pivot.  This cannot be burnished down.  There would not be enough material to properly secure the wheel between the plates. The pivot had to be removed and a new pivot rebuilt.


~^~

The following images  are the steps to re build this pivot.

Here the wheel is chucked in a Sherline lathe. 

The next step is to face-off or cut the bad pivot off.  The face-off tool is used to cut the pivot off.  It is shown in this picture. It is very important not to shorten the arbor length. 

The pivot is removed.  Looking closer in the next image there is a little stub of a pivot.

The next step is to find the center of the arbor.  A center drill is used to find this.  A little starter hole is made.  This is the center of the arbor.

After the center is found.  A drill is used to drill the pilot hole for the new pivot.  The hole is drilled the same depth as the pivot.


There ya go!  
A new pivot.  The new pivot was then polished with emery paper and hardened steal.  The tip of the pivot was then tapered to make it slide right into the pivot hole easy.

Here is another image of the wheel.  Can you tell which pivot was fabricated?

It might look nice but the final test is to see how it spins between the plates.  Here is a video demonstrating the success.

After all repairs have been completed to the movement, The movement is ultrasonically cleaned.  So far the pictures were of the movement before cleaning.  Here is a picture of the movement after ultrasonically cleaned with hi-grade clock cleaning solution.  The pivot holes pith-wooded, and the mainsprings back in their clamps.  This picture shows each train separated.  The time train is on the left, strike on the right with motion works and levers in the middle.


This short video shows the movement running on the test stand.  The movement is running dry and without the tension springs attached.  This is the initial test.  Once all is well, the movement will be oiled and tension springs attached.  All is good.  This initial test runs for about 4 hours.

The strike train was adjusted, the springs attached, and the movement oiled.  The movement was oiled with hi-grade clock oil and the mainsprings were oiled with  hi-grade synthetic oil..  The movement is ready to go back to its owner.  There is no other testing that can be done at this time.  Usually the case is oiled , glass cleaned, installed in case and regulated i.e. adjusted the clock speed.  The strike hammer is also adjusted to get the best quality tone.

Another job well done. 
  

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