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Clocks, Watches/Hermle 791-681 14 day skeleton clock


I have a clock kit my father-in-law purchased 12 or more years ago.  It was never assembled and the kit and movement have been original boxes since then.  I finally got around to assembling it and installed the clock movement and found that the drum that held the spring mechanism was damaged at some point the back panel on the spring drum had decoupled from the drum.  I was able to remove the this "drive" drum and get the back put back on.  But now when I wind the clock, after about two turns of the key, a loud noise comes from the drum and the tension in the spring is gone.  Futher examination of the internal spring, it looks to be broken in the coil.  
Is this repairable, or can I get a replacement spring drum assembly?

Gary, I believe that the mainspring barrel assembly is available, but you might need only the mainspring.  Of course the original mainspring has to be removed and the new one installed, which requires a winding machine or doing it manually, which I do not recommend to anyone is not experienced in doing this.  In the clock repair classes I have taught, I have equated handling mainsprings to that of handling rattlesnakes.  If you are experienced, there is little danger of getting struck.  So it would probably be better to install the complete barrel assembly.  There is one more concern.  What usually happens is that either the mainspring or mainspring ratchet click has been broken and the mainspring has let go with a lot of force.  This will either damage teeth or bend the next arbor (shaft).  These things should be checked before doing replacing any parts.  If this is the case, it would be best to have an experienced clockmaker look at it.  Sometimes if the mainspring is not damaged, it can be formed so the ends catch on the hooks or rivets and will function satisfactorily.  But I cannot tell without looking at the parts.

John Newman
The Village Clocksmith
Old Prattvillage
Prattville, Alabama

Note concerning questions not related to Allexperts:  Because of my commitment to answering Allexperts questions within a prescribed time limit and the large backlog of clock work at my shop, I regret that I cannot answer personal email questions on a timely basis, other than Allexperts follow up questions.  I will try to answer these emails as soon as I can. Thank you for your patience.

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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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