The hole on the left is used to power the strike train which make the clock strike at the top of the hour.
Pendulum wall clock has two winding holes.
Do this every seven days to prevent the clock from stopping or losing time.
Most clocks are 8 day clocks which only need to be wound once a week.
Depending upon the model of your clock there can be 1 2 or 3 winding key holes.
Winding holes in clock faces.
Generally speaking if the clock has a single hole that hole controls the main time spring.
Insert the winding key into the holes located in the dial face.
If there is one hole it is a time only clock.
I have made an innumerable number of house calls over the last thirty two years because of this myth.
Wind the other one or two winding points the same way if your clock chimes on the hour or quarter hour.
For clocks with hanging weights raise the weights using the crank.
The hole on the right is used to power the time train and make the clock keep time.
Winding the arbor in this hole will give the clock power to keep time.
You must lift the weight when winding a chain driven floor clock.
Turn the key clockwise until the spring becomes tight and will not turn further.
Clocks with three winding arbours chime on the quarter hour making a musical tone.
If your clock is cable driven you will wind all three weights with a crank key.
This is a time and strike clock.
Windup clocks and keys clocks that require actual winding will have anywhere from one to three winding holes on the body of the clock often in the back facing.
Winding holes in clock faces are for different functions of the clock.
If there are 2 holes it means that it is a time and strike clock that is it strikes the appropriate hour on the hour and either a bell or strike on the half hour there are always exceptions such as this two train westminster chime clock or a time only clock with an alarm arbour.
If a clock does not strike a gong on the hour it is technically called a timepiece.
It is not harmful to wind the clock more often.
A clock that strikes on the hour has two winding holes one for keeping time and one for striking.
I have set up thousands of clocks on outside walls and have never heard a complaint from a single customer that it has caused any kind of problem.
To prevent over winding your cables allow the entire pulley to be visible under the face of the clock.