Mechanical Watches

Automatic watches are charged by movement. These watches do not contain batteries. By moving the watch as it is worn on the wrist, power is stored within a spring in the watch. When fully charged, the power reserve typically lasts between 24-48 hours depending on the movement. If an automatic watch is fully charged and then not moved, it will run out of charge within this time.

Winding the watch

When an automatic watch stops completely after running out of charge, it should be ‘initiated’ by winding it manually. This means turning the crown clockwise approximately 30-40 times.  Always re-initiate your automatic watch after it stops completely. To minimize winding the watch, wearing the watch regularly will renew the power reserve.

Accuracy

It should also be noted that automatic watches are generally not as accurate as quartz watches. It is not abnormal to notice time variances of -30 to +30 seconds per day and is dependent on the type of movement. The NH35 movements used in our watches are usually tested to have a variance of  less than, +5 to -5 seconds per day.

It may seem strange for your watch to speed up when the power runs down, but it’s perfectly normal.

Energy released from the mainspring causes the balance wheel to turn back and forth. That oscillating motion is how a watch measures time. As a rule, the steadier the rate of oscillation, the more accurate the timekeeping will be. However, the rate can fluctuate depending on how much power is stored in the mainspring.

Typically, a watch’s rate is steadiest when the power reserve is above 90 percent. When the energy level drops below that point, it very slowly beings to lose the torque needed to fully drive the balance wheel. This causes a drop in amplitude, which is the number of degrees that the balance wheel rotates each time it turns. When this happens, the rotations become shorter and take less time to complete. As a result, the rate increases, and your watch speeds up.

What are the major factors influencing accuracy?
The fragile metal parts of a mechanical watch are easily influenced by environmental factors such as temperature, magnetic fields, gravity, and shock. Also, conditions of use such as regular usage time, movements of your arm and winding state of the mainspring can influence the gain / loss in accuracy.