The Seth Thomas “Office No. 6″ is a wall clock in a rectangular wooden case. Time-only and time and strike versions were available. The earlier ones had a removable scroll top and a bracket base, but by 1924 it was being made in a plain case.
This example looks similar to that in the photo labeled “1924″ in Tran Duy Ly’s Seth Thomas clock book. The case is dark mahogany, 31 inches tall, 15 5/8 inches wide, and the dial has a 10 3/4 inch time track. The movement is 8-day time only, no. 123 E. I first overhauled this clock in 1999 (polished pivots and installed 5 bushings). It ran until 2009, when the click broke (an uncommon occurrence).
I cleaned the movement and did the following repairs:
- Installed a new click;
- Installed a new mainspring, as the old one had a squeaky action even after cleaning and oiling. I installed a Merritt’s P-1956 3/4 x 0.0165 x 96 inch mainspring (the new spring opened up to 5 1/4 inch diameter after being wound and unwound 5 times).
- The pivots, which I had polished during the last overhaul, were still in excellent condition.
This movement has stopworks for the mainspring, I set it up so that it stops the winding when the spring is one turn from being fully wound. The case has a beat plate, and the motion of the pendulum measured on the plate is as follows:
- Escape arc: + and – 0.75 degrees
- Wound up: + and – 3.3 degrees
- Rundown 3 days: + and – 3.2 degrees
- Rundown 7 days: + and – 2.8 degrees
The paint on the dial was flaking badly, and the customer wanted it restored. I had it repainted by The Dial House in Dallas, Georgia.
Here is a slide show of the clock and its movement:
Repair job 1891.
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