I repaired this Seth Thomas shelf clock and installed new mainsprings because they had previously been replaced with springs that were too strong.
The case is 22 3/8 inches tall and 14 3/4 inches wide. The minute hand is 2 13/16 inches long. I replaced the dial because the original was in very bad condition. Note that the door is not present in the photos below (the customer didn’t send it with the clock to prevent breaking the glass).
Repair job 5726.The movement is marked “8 1/4″ on the lower front. Later, Seth Thomas named this movement No. 89. It is an efficient running movement due to its deadbeat escapement.
I polished the pivots and installed bushings. The mainsprings in the clock when I received it were as follows:
Time: 3/4 x 0.0178 inches, Strike: 3/4 x 0.018 inches.
I installed thinner new springs to make the movement have a longer life. They are no. 77.303 from R & M Imports. They are made of beautifully blued steel, of the following dimensions:
- Time: 3/4 x 0.0161 x 120 inches
- Strike: 3/4 x 0.0162 x 120 inches
These thinner mainsprings will reduce future wear to the time and strike mainwheels.
