Expert: Martin Meyer - 3/17/2008

Question
I have a Howard Miller Grandfather Clock with a Hermle Movement with three cable weights. This clock runs 7 minutes fast per 24 hour period. When I adjust the pendulum up or down it has no effect on the speed of the clock. The movement is a little more than a year old and this problem started when I moved the clock to paint the room it was in. Could you share any ideas as to what my clocks problem is? Thank You in advance for any help you can provide. The person that I had to replace the movement doesn't seem to know how to fix this problem either.

Answer
Hi Rick,
    Theoretically, lowering the pendulum disk must make the clock go slower. The effective length of the pendulum is the sole determiner of the rate of the clock.
    First, make sure that when you turn the regulating nut down, the pendulum disk also moves down, to seat on the top of the regulating nut. Pendulums are often tight on the pendulum rod, and lowering the nut will have no effect if the disk does not also lower.
    Next, check my previous answers for a photo of the correct connection of all parts of the pendulum assembly. Often in moving, these parts become disconnected and the clock will not keep time.
    Finally, are you sure that the problem began when the clock was moved, and not when the movement was replaced? I don't know the reason for this, but some replacement movements run faster than the original. The cause may be due to the heavier suspension springs used in some newer movements. If you adjust the regulating nut all the way to bottom, and the clock still runs fast, this may be your problem. The remedy for this is to modify the pendulum leader to be about 1/2" to 1" longer. This job requires silver brazing, so probably needs to be done by a professional clock repairer.