Expert: Martin Meyer - 3/21/2009

Question
Hi! I have a cuckoo clock that's pendulum will only stay moving if I apply downward pressure on the weight,the clock does advance in time when I'm doing this, but when I stop pulling down the pendulum stops. It's a one day clock, and has a 275 mark on the the pine cone weight. The cuckoo works but the cuckoo sounds slow and weak. When I use a 420 weight on the clock the pendulum still does the same thing, but the cuckoo sounds much quicker and brighter. Just wondering if you might have any suggestions on how to keep the pendulum moving on its own, I'd really love to get this clock working! Thanks so much for your time!

Answer
Hi Diana,

The actions that you describe are indicative of a movement which is worn out. Over time, the bearings for the gears in the clock wear out, and the cumulative friction in the gear train increases to the point where the clock will not run or strike. The remedy for this is to have the movement replaced with a new one of the same make and model. Cuckoo movement installation is somewhat complicated, and I would recommend that you have the work done by a professional clock repairer.

Your weight is 275 grams. This is the correct weight for the most common one-day movement. The 420 gram weight is for a one-day movement with a much longer pendulum (28cm versus 19.5cm). Pendulum length is measured from the post at the top of the movement which the pendulum assembly attaches to, down to the center of the pendulum bob (leaf). The extra force delivered by the heavier weight may temporarily make the clock strike or even run, but will soon wear the movement out even more, to the point where it once again will not run. Only the correct weights should be used.  http://www.clockmasteronline.com