Rules and Practice for Adjusting Watches

rvatory

ume the natural condition before being placed in, or changed from, one degree of temperature to another. After the three or five day test, according to the grade of the watch, the average of the daily rates in each temperature is considered in making the comparison and arriving at the total variation. The total error is then considered in

ercial

stic, the tests are generally made for twenty-four hours in each temper

ng to be gained by this in regular work, although for a special rush job a day's time may be saved. Watches are always expected to be in first-class condition and such features as close fitting pivots or dirty oil will prevent any dependable

s as much as possible. The first test is made in heat at 90° Fahr., then in normal tem

in to condense. The time should therefore be quickly noted and the watch replaced in the higher tempera

d Method of Calcu

tch need only be set at the beginning of each test, as deductions can be made from the entries

e watch to correct time, place it in the heat box and at the end of twenty-four hou

ed in the second square of first column. Assuming the time to be just correct, place a zero as shown. Next wind the watch and place it in the cold box, and assuming that the variation is sixteen seconds fast at the end of twenty

............. Make

4 + 4

0 - 4

16 +16

2

ter this in upper square of second

quare above we carry it out in second column as -4. In the lower square of first column we find +16 and as this is a gain of

e the normal rate of -4 in the second column and subtract +4, from +16,

comparison and wherever large quantities of watches are adjusted, it is generally the custom to use the higher temperature for this purpose and the rate is stated as either

the Normal

, its importance consisting only of allowing the metals to return

t to the extreme of cold, there will be a period of time during which the metals are readjusting themselves to the natural form, and the variation in tim

preferred. However, by allowing an intermediate day at normal temperature we have the assurance that the hairspring is at the same

e in addition to the five days required for observatory testing in each temperature that the watch be subjected to an intermediate day in each, instead of in normal, before consideri

acters Used on Rate Cards

is used as denoting that the watch is running faster than the standard time an

s indicated, to attain the correct standard of time. When the signs are identical in a column it is necessary to subtract the lesser from the greater and the result is the variation. There

ormal rate in the second square is not considered, for the reason previously explained and the rate in cold is shown as -1. The total varia

............. Make

+ 8

AL +

+19

ecreasing the Extr

emes may be raised five or ten degrees to advantage. If the watch is to be used in a cold climate, the extremes may be lowered this amount. The metals, however, can only stand the strain of ex