Pendulum for Jauch movement

Posted: Fri Apr 02, 2010 3:39 pm     Post subject: Pendulum for Jauch movement

I have a Jauch Westminster movement with 2 sets of 4 hammers and 3 weights. The back plate is marked as follows: Jauch, P.L. 61 cm, West Germany, 9 74, 60-500/Ke/E. I have the proper suspension spring, leader and pendulum hook. I would like to use a lyre pendulum and obtained one which is 71 cm long with a 6 1/2" brass bob. The movement runs extremely slow with this pendulum, since it is too long; however, before cutting its fancy metal work shorter, I would like to know if anyone can give me an idea as to the approximate length the pendulum should be, while keeping some extra length for speed adjustment, and also what approximate weight should be used for the center weight. References to this movement on the Net vary from a skinny wooden pendulums with a tiny bob to heavy lyre ones with huge bobs.

Posted: Sat Apr 03, 2010 5:11 am     Post subject:

the pendulum is 61cm by PL 61cm. Since you are using a universal style pendulum you will probably want to cut small pieces of the pendulum off until the clock runs at the right speed.

Posted: Sat Apr 03, 2010 1:57 pm     Post subject:

Thnx for the response. How would you determine the center weight for the pendulum? For the chime and strike sides, I kept adding small weights at a time until the respective hammers reacted properly on the quarter hour and hours. Does the weight for the pendulum affect the speed of the swing or the speed of the whole movement? Wouldn't too heavy a weight cause premature wear on the gears? A little more advice would really be appreciated.
One more question, is it better to use silicon spray instead of light oil. Silicon is not sticky like oil and therefore would not gather dust in the long run.

Posted: Sat Apr 03, 2010 8:58 pm     Post subject:

I would post these questions on the NAWCC message board under clock repair, many more technical folks over there.

http://www.nawcc.org