Why the swing of the balance wheel becomes smaller and the beat faster than normal
Because the hairspring is not flat, there will be waves when stretching; rubbing the pendulum splint, wiping the pendulum beam or the center wheel; rubbing the upper and lower layers of the frame-picking hairspring;
Why does the watch stop every hour?
A problem with the core wheel or gear teeth generally causes this fault. If it is an old watch, it is mainly related to the wear of the shaft eye of the splint. The wear of the shaft eye will cause the core wheel to tilt in the sling, which will quickly cause the front end of the minute hand and the dial. The characters or the arrows indicating the seconds on the clock will rub against each other, and the two-hand and the thin watch will rub against the inside of the watch glass.
Why does the watch jump the calendar at noon?
If this happens, it only means that the way of adjusting the meter is not correct. There are 24 hours a day, but the watch cannot tell whether it is day or night. The watch calendar is in 24-hour format, so if you directly adjust to the current time, you may encounter a situation where the calendar jumps at noon. The correct method of operation: First of all, you need to avoid the restricted area of the calendar (8:00 p.m. to 2:00 a.m. the next day), then push the crown back to the first gear, start to adjust the calendar, and the calendar is adjusted to the day before the current date. Then turn the crown out to change the time, bring the calendar to the present day, and adapt to the current time.
How much error is standard for a mechanical watch?
The instantaneous error range of travel time for qualified mechanical watches stipulated by the state is -70~+135 seconds per 24 hours.