Moving it up pushes the “bob” (the round disk) up so the clock will run faster. If you turn the nut as to lower the “bob”, the clock will run slower. The pendulum disk is moved up or down by turning the adjustment nut. 1) Start by seeing exactly how far off the time is over a 24 hour period.Set the grandfather clock correctly by using your cell phone.oving it up pushes the “bob” (the round disk) up so the clock will run faster. If you turn the nut as to lower the “bob”, the clock will run slower. The pendulum disk is moved up or down by turning the adjustment nut. 1) Start by seeing exactly how far off the time is over a 24 hour period.