Seth Thomas 103A runs slow

[Lloyd M]

I have a little desk clock with a balance wheel in the shop now that needed cleaning and balance staff replaced. After I had that done, added a couple bushings, cleaned and oiled the movement, it runs slow. The balance spring was pretty bent up and I straightened it to match the inside curvature as best I could, and the beat is pretty good, but the rate is about 16,180 BPH. I don't know what it should be, but am looking for suggestions to solve the problem.

 

[harold bain]

Perhaps shorten the hairspring by moving it and putting the pin in a slightly different location?

 

[Lloyd M]

I have a little desk clock with a balance wheel in the shop now that needed cleaning and balance staff replaced. After I had that done, added a couple bushings, cleaned and oiled the movement, it runs slow. The balance spring was pretty bent up and I straightened it to match the inside curvature as best I could, and the beat is pretty good, but the rate is about 16,180 BPH. I don't know what it should be, but am looking for suggestions to solve the problem.

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I can try that - I tried to set the balance spring so the pallet pin was close to center to get a good beat.
Will try though
Thanks

 

[Uhralt]

After shortening the moving part of the hairspring you need to newly set the beat. There is usually a split collet that attaches the hairspring to the staff. Put a small screwdriver is the split and rotate the balance wheel slightly to set the beat. Several trials may be necessary until it is perfect.

uhralt

 

[Lloyd M]

After I removed the balance wheel I found that the balance spring was loose on the shaft, so I removed it and pinched it closed a little on a smaller size drill bit, went to put it back on and the spring fell off the collar, so now I have to find a replacement!!
If anyone has parts from the 103A, let me know. I will put a request on the parts wanted list also.

 

[bangster]

Some days nothing goes right.