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Clocks, Watches/Centurion 35 day clock keys


Centurion Regulator
Centurion Regulator  

Centurion Regulator
Centurion Regulator  
I purchased this regulator model # 650 KB made in Korea but without keys. Could you tell me what keys I need to purchase.

Thank You
Ursula Jarrett

Ursula, I have a Centurion in the back of my shop.  The winding arbors are 3.6mm across the flats.  The catalogs list a 3.6mm key as a #6.

CAUTION!  Key sizes and some manufacturers' clocks do vary in size.  I tried an American #6 key on the Centurion winding arbors and it fit correctly.  I found about 5 play which is good.  It should be no more than that.  However, I always recommend that a key be fitted to the movement because of variations and wear.  I do not sell keys in my shop without checking them with the clock, unless they are for certain modern production clocks, which are fairly standard. If the key is a little too small, it will not go on the arbor all the way.  if it is too big, it can slip and cause damage to the clock and personal injury to your hand.

Clock suppliers can be found on the Internet that have these keys.  Most companies can be Googled and have On-line catalogs.  Some I use are Timesavers,  Merritts Antiques, Black Forest Imports, R&M Imports, Ronell, and Mile-High.  When you select a key, choose one with the extra large wings, as the Asian 31 to 35 day clock mainsprings are rather powerful, and a loager key makes it easier to wind.  For example, Timesavers part number is 10179.  This is for the American size, not the Swiss size.  Don't try to hurry winding a clock.  Again, this can cause the key to slip and result in what I described above.

I hope this helps.  Just remember to make sure the key fits properly.

John Newman
Located in Old Prattvillage
Prattville, Alabama  

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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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