It is possible to almost entirely eliminate this duplication of work if proper care is exercised in examining the pivot and jewel with a good glass before replacing and in using oil from a closed receptacle in which it has not been possible for dust to collect.
The point raised in this instance is that the improvement desired is not assured because of merely going through the operations of doing the work.
It is necessary to actually remove the cause and then keep it removed. The proof is found in the improved motion and it would hardly be worth while to retest in positions until this improvement was obtained.
Proper curvature of the over coil within the range of the regulator pins is another feature that may be corrected and the correction unconsciously destroyed in replacing the balance or in centering the spring.
A slight kink in the coil close to the regulator pins may cause the spring to be forced out of center when the regulator is moved, or it may cause the coil to lay against one pin and cease vibrating between the pins. This would cause a gain of some seconds per day when the regulator had actually been moved to cause a slower rate.
These two examples are introduced to convey the idea that it is necessary to actually produce the corrections or alterations in any instance and that close timing and close position rates depend more upon this practical execution and understanding as displayed by the watch repairer than they do upon a high degree of technical knowledge.
Personal instruction of watchmakers in adjusting has demonstrated in most instances that the refinements are not considered seriously enough at first, but that consistent practice and reference to the rules soon make the proper impression, after which results are attained in less time than was at first required for faulty execution.
[80.]Truing the Balance.
The balance should invariably be true in the round and flat and always in poise before it is placed in the watch.
It is at times pardonable to pass a balance that is not perfectly true in the round, especially when the watch has been repaired on several occasions and it is noted that the rims have a tendency to become set slightly inward or outward after having been perfectly trued. This shows a natural tendency of the metals to find a permanent position which may be slightly away from the true concentric form. A balance of this description may be poised as it is and often will produce better timing results than would be gained by perfect truing and subsequent regulation during readjustment of the metals.