Clocks, Watches/Seth Thomas


I recently acquired a Seth Thomas Grandfather clock form my mom. On the back of the clock it has Mov't. No. A407-001 and E899-503 ISS. 1  It was purchased in January,1973.  The clock has not run in a long time but is in very good condition. I cleaned and oiled the clock and it started to run and chime.  The issue Iím having is it is running fast, I keep moving the ball down but it still runs fast.  I saw somewhere that it could be a weak or short swing. Could you tell me what would cause this and is it repairable?

Thank you,

ANSWER: Mike, if a clock has a weak or short swing, it will stop.  It could be either the pendulum is the incorrect one and is too short or the bob is just too high.  When you turn the regulating nut (at the bottom of the pendulum bob) so it goes lower, is the bob seated firmly on it after the adjustment is made?  Sometimes the nut will move down but friction keeps the bob from following it.  Therefore, the adjustment is not affective.  Always make sure the bob is seated on the bob before and after adjustments.  Another problem is that the escape wheel is damaged and the escapement pawl assembly (the part that rocks back and forth and goes tick tock)is skipping teeth.  That would have to be repaired by an experienced clockmaker.  To get an idea of what is wrong and how to resolve it, tell me how much time it is gaining in an hour or in a day.  Then we can go from there.

John Newman
Located in Old Prattvillage
Prattville, Alabama


---------- FOLLOW-UP ----------

I need to clarify that it does eventually stop running.  I checked the bob adjustment nut per your note and it is attached to the bob, which moves up and down when adjusted.  I borrowed a video from a Library regarding Deadbeat Escapements so I could use the correct terminology. The escapement I have is a deadbeat with adjustable Pallets, I notice that when it is running, the top of the tooth hits the Exit Lift Face rather than the Lock Face.  The sprocket has a small amount of backlash at that point, also the sound is not a clean tick-tock noise.

Thank you,

Mike, the adjustment of a deadbeat escapement with adjustable pallets would require a rather precision adjustment procedure from someone with experience.  On a verge with solid pallets, the verge can be moved up and down for the proper pallet entrance and exit.  If the adjustable pallets on your movement are not loose, I would not attempt to adjust them.  That is usually not the problem.  It is usually the position of the verge or worn or bent escape wheel teeth. This would cause the escape wheel to skip teeth and run fast.

It would probably be best to have an experienced clockmaker look at it.  Sorry I could not help you more.

John Newman  

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John Newman


As I am not a certified appraiser I do not give values of clocks over the Internet. There is very little published information on what I consider to be the value of "modern production clocks". However, considerations are what the clock originally sold for, the condition of the case and movement, and particularly the area in which you live, the demand and the economy. ALSO, WATCHES ARE NOT MY FIELD. However, I can advise the clock owner on proper maintenance of a clock to keep it running, small corrections and adjustments and how to move a clock without damaging it. I can also advise on obtaining parts for clocks. As clock case model label numbers are difficult to relate to the movements, it is helpful if you can give me the information usually found on the movements themselves. Modern clock movements usually have the information on the back plate of the movement. I have been a clockmaker for about 40 years and was plant engineer in the mid 90's and later operations and engineering consultant at Emperor Clock Company in Fairhope, Alabama. I now have my own clock shop in Prattville, Alabama.


One of my greatest accomplishments was traveling to China to assist a clock factory in building clocks to the standards which we required at Emperor. With the proper specifications and quality control, some beautiful clock cases were built. The factory people from the wood carvers to the plant manager were very congenial, friendly and I left a lot of wonderful friends when I returned from my trips.

NAWCC (National Association of Watch and Clock Collectors) 30 years Prattville, Alabama Chamber of Commerce

Horological Times, a publication of the American Watch and Clockmakers Instute. Collaberated column author, with Photos and ideas for clock movement conversion article.

Associate of Science Mechanical Engineering Technology Emperor Introductory Clock Repair (Eventually taught a portion of the class after becoming employee)

Awards and Honors
Small Business of the Quarter (Prattville, Alabama) Leadership Class of 2009 (Autauga County, Alabama)

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