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SWCC Second-Hand Self-Winding Clock Co. movements offered with missing parts.

eskmill

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At Marts and auction sites we often find whole clocks or usable or salvageable movements made by the Self-Winding Clock Company. There's often some part missing; the pendulum or the hands, or the threaded nut used to retain the long hand.

Worse, sometimes the wrong nut has been used cross-threaded onto the end of the center arbor because the original nut is lost. :mysad:

For what it is worth for the most commonly found SWCC movements: the correct thread pitch for the center arbor to retain the minute hand is USF 3-48. The other two knurled nuts: one on the minute wheel stud and the correcting lever stud are USF 2-56 threaded.

There are other less-common sizes such as for clocks with unusual or very large dials.

Note also that sweep-seconds movements use different hands nuts. The sweep-seconds hand has a USF 2-56 thread and the minute hand is retained by a spring clip.

I don't know of a ready source for these small knurled nuts; I've had to make them.
 

eskmill

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Last March I stated in part: "For what it is worth for the most commonly found SWCC movements: the correct thread pitch for the center arbor to retain the minute hand is USF 3-48. The other two knurled nuts: one on the minute wheel stud and the correcting lever stud are USF 2-56 threaded. "

I should have made it clear that the center arbor hands holding nut thread pitch USF 3-48 applies to the Style F movements generally and not all Self-Winding Clock Company movements.

A recent experience with a SWCC style A movement reveals the center arbor thread pitch is different than on the more common F style movements. The A movement center arbor thread is a USF 4-48. This larger thread may apply to the style C movements as well.

Curiously, there are likely more Style C movements extant than the later produced Style A movements which may have been manufactured "in-house" by the SWCC or under contract by other than Seth Thomas. Style A movements have serial numbers beginning with 29nnn.