Clocks, Watches/Seth Thomas


Hi Marilyn, thank you for your last answer it was spot on! If you will allow me another, I have a Seth Thomas "Medbury" 6W 8-day, Catalog #1300 mantel clock. The movement is a General Time Company A Two (2) jewels. The oil in the pivots has been restored and the pivots look good. I ran it in the test stand for a couple of weeks to tweak in the time. The speed adjustment is maxed out and it is still losing time (about a minute a day). Before I do a full dismantle I thought I would check to see if I can add another layer of missing knowledge if you would be kind enough to pass on to me. How would you approach this problem please. Thank you!


Hi Rich,

Is this a floating balance?
If so then the adjustment can be maxed out.

I would clean any dirt out of the pivot holes with a watch rinsing solution. This dissolves the the old oil and loosens up the dirt. I use "fabric paint brushes" to dip in the solution and clean the pivot holes and the inside pivot shoulders. Then put fresh oil on. These paint brushes don't leave hairs behind.

Do you know how to let down mainsprings?

I would also clean and regrease the mainsprings. They could be sticky and causing friction.

If this doesn't work then you may need to punch two pieces out of the floating balance. One on each side to make it balanced.

How old is the clock? There should be a date above the numbers on the lower right hand side of the movement where it says the movement 320-020. It's either two numbers such as 84 for the year 1984 or a letter. The letters started in 1988 with A, 1989 is B and so on...

Hope this helps,

Clocks, Watches

All Answers

Answers by Expert:

Ask Experts


Marilyn Bellotti


This is for advice only. ~Most~ repairs need a professional. If I can help you with an adjustment that can set your clock back in order I will try. I can not write a chapter on clock repair. I will point you in the right direction and you will have to do your own research on how clocks work for more intense repairs. -No Watches -No Appraisals. Search ebay for past sales for that information.


29 years repair experience

Certified Horologist

©2016 All rights reserved.