Reader Disagrees With Method of Repivoting Arbor

From The American Horologist magazine, May 1946

Reader Disagrees With Method of Repivoting Arbor 

Editor, The American Horologist:

In regard to Mr. G. W. P. Silvester's, "How? " in the March issue of the American Horologist, I would like to strongly criticize his "usual method" of repivoting an arbor.

As I understand the instructions, he simply cuts a new pivot on the old arbor and then makes a bushing long enough to reach the shortened arbor.

While this method may be justified in exceptional cases, although I can think of none at this moment, I would like to point out that if this newly cut pivot should happen to get broken, and if the pinion is part of the arbor, then what would he do? Obviously, it wouldn't be possible to continually keep shortening the arbor and even after doing it once, in many cases there would not be enough stock left to do anything except repivot in the conventional manner. However, this time it would be more hazardous than the first time.

Mr. Silvester says, "It is not necessary to drill all the way through" the long bushing he rivets into the clockplate. This dead end type of bushing should, I maintain, be very carefully made to obtain an accurate fit and a clean, polished bearing surface and is not as desirable for many reasons, as the open ended bushing.

Mr. Silvester's method of repairing a deeply cut pivot is absolutely Old! The idea of turning a thin, true pivot from the bent or deeply cut pivot and then turning another thicker pivot adjacent to it and this time drilling through the plug so that the small pivot may be allowed to remain on the arbor, is preposterous! In any event, it is not desirable to have extra long bushings projecting through the plate, if for no other reason than the added danger of damaging or loosening them during cleaning.

Mr. J. E. Coleman's method, described in your December issue entitled, "Why?" is far superior in every way.

R. K. Eartridge, 

1509 East Helen Street, 

Tucson, Arizona.