Quartz Pendulum Hits the Sides
Do you hear a bonk, bonk, bonk all day and night? This is because the pendulum bob keeps hitting the sides of the clock case with each swing. It may not stop the clock, the clock will work just fine. However the knocking sound of the pendulum hitting the sides of the clock case can be annoying. Lucky for us the correction is fairly simple on these pendulum quartz clock movements.
A quartz pendulum hits the sides of the clock case happens when the magnet on the movement is too strong. Either the magnet is too strong or the bob on the pendulum is too wide. Both of these problems can be fixed easy.
The pendulum bob diameter can be swapped out for a smaller size. The alternative fix is to lessen the strength of the magnet on the back of the movement itself. I have heard of this being done with masking tape with good results. It just creates a slight barrier of the magnetic pull enough to reduce the overall swing of the pendulum. Either way, putting tape on the back or swapping out the bob, you will be left with a quiet clock again.