This is a small problem often plaguing the general public, and I myself have been haunted. Ordinary calendar mechanical watch itself at the end of the month and the end of February have to be manually adjusted; calendar to be adjusted once a year by the end of February; perpetual calendar theoretically do not adjust, but you want to ensure that mechanical calendar does not appear stopped, that operation is Another heart ... Therefore, the mechanical watch often encounter the situation of the calendar is not allowed, the most common is not to jump at night instead of jumping at 12 noon. Before I did not become a clock and watch media noon jump calendar problems are stupidly opened the crown, leaving the watch stopped for 12 hours. For example, let the watch stop at eight o'clock in the morning, have to remember in the mind at eight o'clock in the evening let the watch continue to go, can not affect their sleep at night. Looking back now, this method is really stupid though it works. The correct way is to dial the hour hand or callback (depending on the circumstances) 12 hours, the table instantly adjusted. If your mechanical watch is not the case of noon skip calendar, but the calendar in advance or a day or more slowly, you can adjust the speed by adjusting the calendar stalls, which need to avoid the 22:00 to 2:00 this period of time, Avoid sweeping teeth, damage the watch movement.