Adjusting the watch calendar

      Calendar mechanisms have a restricted period during which the date should not be adjusted. This period typically occurs between 22 pm and 2 am, during which the date change is in progress; adjusting the date during this time is strictly prohibited.

Situations requiring calendar adjustment:

1, the watch changes the date at midday.

2, the watch displays the incorrect date (including during the transition between months of different lengths or leap years).

Methods for calendar adjustment:

      We know that a watch's calendar mechanism only advances once every 24 hours. However, the hour hand rotates twice in that time. In the first scenario, the watch changes the date at 12 pm; this is easily corrected by advancing the hour hand clockwise by one full rotation. For the second scenario, there are two ways to correct it. Most modern watches with a calendar (including day-date) function have a crown with 3 positions. When the crown is fully pushed in, it is in the 'normal position' for winding. When fully pulled out, it allows for time setting. Between these two positions is a middle position used for quick-setting the calendar. You must carefully move the crown to this position and rotate it to set the date disc accurately. Older watches often lack this quick-set feature, requiring you to advance the hands clockwise. A shortcut is to advance the date, then turn the hands anticlockwise back to the 7 o'clock position, and then advance them clockwise again to the 12 o'clock date-change position, avoiding the need for continuous clockwise rotation.

Precautions:

      Some calendar mechanisms are adjusted using a button on the case, where each press advances the date by one digit. Others are adjusted by pulling or pushing the crown. Regardless of the method, do not use the quick-set function while the calendar mechanism is in its active change period.

      In some day-date mechanisms, the day changes several hours after the date, particularly in Japanese-made watches. For double-calendar watches, the direction of crown rotation usually determines whether the date or the day is being adjusted.

      If your calendar mechanism reverts the date when you turn the hands anticlockwise, you must adjust the date by advancing the hands clockwise. Significant or prolonged time-setting can affect the gear teeth and increase wear, so always adjust the hands gently.