Repairs made. New balance staff and cleaned. The first test in five positions showed a variation of twenty seconds as per second column Fig. 20. It will be noted that in four of the positions the rate was quite close and that the pendant right position had an extremely fast rate.
A casual investigation indicated that all points relating to the spring, regulator pins and balance were reasonably satisfactory but that there was a slight falling off in motion in the pendant right position. Further investigation of this feature disclosed a slight striking sound when the watch was held to the ear in this position. The dial was removed and the bankings were closed to drop whereupon it was discovered that the fork was long on the inside, or when the receiving stone was locked on the escape teeth. This prevented the roller jewel from passing through the fork freely as it did on the opposite side.
The balance pivots had the limit of allowance for side shake which aided the cause of the roller jewel in striking.
| No. ...248027........... Make...Hamilton........ | |||||||
|---|---|---|---|---|---|---|---|
| D U | + 1 | + 1 | + 3 | + 3 | P | ||
| D D | + 2 | + 1 | + 7 | + 4 | |||
| P U | + 4 | + 2 | + 8 | + 1 | |||
| P R | +22 | +18 | +12 | + 4 | |||
| P L | +20 | - 2 | + 8 | - 4 | |||
| 20 | 8 | ||||||
After correcting the roller jewel shake and readjusting the slide and guard pin freedom the next test showed a variation of eight seconds in the five positions as per fourth column Fig. 20. The side shake of the balance pivots was not detrimental after the real cause of the variation had been removed and therefore no correction was required in this respect.
If the error in the escapement had not existed and if the watch had shown the same rate with all points appearing to be satisfactory, the trouble would most likely have been found in the poise of balance with the upper side heavy in the pendant right position.
The time consumed in making the correction was about one half hour.
[68.]Example No. 6.
Elgin. B. W. Raymond. No. 4,109,543, Open Face, 15 Jewels.
Repairs made. New fourth pinion; new end stone; mainspring; refinished balance pivots and cleaned. Note that this was only a 15-Jewel watch.