Seth Thomas Tambour Mantel Clock with Enamel Dial

I recently overhauled this Seth Thomas tambour mantel clock with enamel dial. The case is 21 inches long. The movement is No. 89AL, a version of the popular No. 89 movement with solid back plate and active striking on the half hour (as opposed to passing strike).

Both mainsprings are original Seth Thomas springs and are 3/4 inches wide and 0.017 inches thick. They provide plenty of power to operate the movement.

Here is a movie of the clock, showing it operating and striking:

Here is a slide show:

Repair job 4819.

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  1. The new mainspring I like best for the no. 89 is the 3/4 x 0.0165 x 120 inch spring. The original springs were 108 inches long.

  2. On the Seth Thomas tambour with the 89 Al Movement that you showed on your website what was the length of the mainspring
    I am about to work on one with a broken time spring and I was going to order one before I started
    Clock repair is a hobby
    So any help like you website – I use

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