Rules and Practice for Adjusting Watches

by Walter J. Kleinlein

As a rule it is best to begin at either end of the watch, and if it is to be taken down the best place to begin is usually with the balance and examine each part as it is removed until the barrel has been reached. If it is not to be taken down, just as good results will be obtained by beginning the examination at the barrel and finishing with the balance. Sometimes watchmakers of considerable ability will demand as a basic consideration that pivots be fitted with very little side shake and that end shakes also be quite close if close time is to be expected.

These presumed to be, wide side shakes and long end shakes, very often have nothing whatever to do with the absence of a close position rate and frequently are absolutely necessary for good performance of the watch and proper space for oil.

The importance of reasonable limits is of course granted, but it is very detrimental to have pivots too close fitting and more stoppage and irregular time keeping can be traced to lack of freedom than can be traced to excessive shakes.

If the repairer is not familiar with accepted standards of side and end shakes, he can improve his judgment by examining watches of the higher grades and comparing the results with those found in cheaper makes of watches.

Such examination will invariably disclose the fact that fine watches receive very careful consideration in this respect. The center, third and fourth wheels generally having from 0.03 mm. to 0.05 mm. freedom for end shake and 0.015 mm. to 0.02 mm. for side shake. The escape wheel, pallet and balance will be found to run quite uniform at from 0.02 mm. to 0.03 mm. freedom for end shake and from 0.0075 mm. to 0.0125 mm. for side shake. The smaller and thinner watches generally favoring the lesser figures and the larger and thicker watches favoring the higher.

This uniformity of freedom will be found absent in cheaper watches; for instance, a center wheel may have 0.02 mm. end shake and 0.01 mm. side shake which would be very close fitting for large pivots. The fourth wheel may have as much as 0.08 mm. end shake and 0.03 mm. side shake which would be too great. The pallet may have 0.05 mm. end shake and the balance 0.01 mm. and in this instance the short end shake of the balance would be more detrimental in most instances than would the longer end shake of the pallet. The variation will even be found to exceed these figures and when they are found in connection with thick, straight hole jewels they often interfere with a close position rate and with regularity of time in service. The interference in timekeeping is considerably aggravated in cases where one pivot has excessive side shake and the opposite pivot is close fitting, as this tends to cause almost certain binding of the close fitting pivot as soon as the power of the mainspring is applied.

The end shake and side shake allowance for the barrel depends considerably upon its style of construction. Safety barrels constructed so that the arbor revolves with the main wheel, when the watch is running, may have about the same end shake and side shake as applied to the center, third and fourth wheels, and if the pivots of the arbor are quite large they may have a trifle more side shake.

As a rule larger pivots will stand more side shake than smaller pivots; this, however, does not apply in the case of large bearings, such as safety main wheels that revolve around a stationary arbor, or going barrels where the entire barrel revolves around the stationary arbor when the watch is running.

In such instances the main wheel or barrel should have from 0.03 mm. to 0.05 mm. end shake on the arbor and should be just free for side shake.

The arbor which turns only when the watch is wound requires merely freedom for end shake between the plates, as well as for side shake where the pivots pass through the plates.