The tick remains elusive
  • I can only manage some 15 seconds of pendula swing rather than the 50 seconds Dave recommends, individually or joined together. The frame is tight and the arbors are well thinned and smoothed with (ultimately) 600 paper. I guess it is because of this that I cannot get sustained motion from the drive weight.

    Any ideas welcomed. Thanks David
  • I can not begin to explain the frustration I had getting clocks to run when I first started building, clocks would stop for no apparent reason, I could just not find the problem, it made me want to bang my head against a very hard wall.

    Admittedly, it was also to do with design, you have got to start somewhere, but it was mostly friction, a simple fact that I did not realise would have such an adverse affect.

    I hate saying the problem is friction, as it is ultimately a frustrating answer.

    I presume the Pendula are made as the instructions, the Pendula arbors sit securely in the back of the Pendula.

    Check that the ball bearings also sit securely in their rebates, also that there is a gap between ring stop and ball bearing, and of course the arbor should slide back and forth with total ease, as in the ball bearing tutorial video.

    By the time the drive force has passed through the gear train to the Pendula it is only a few grams, so if the Pendula are not swinging as should, then they will stop the clock.

    If I understand correctly you have finished the clock? If this is the case also check that all other arbors run with as little friction as possible. It is preferable to have the arbor too loose in the bearing than maybe just that little bit too tight.

    And now, when I have a clock working as should, and it stops (quite often happens after approx. 2 weeks of hanging) I do not hum or arr, but rather take it apart and thin all arbors and check the bearings. It saves me wanting to bash my head against that brick wall.


  • Stand parallel with the wall and look at the pendula. Eye the pendula up using the frame as a reference, make sure they are swinging exactly parallel with it. If not , loosen off the stop rings, pull the shaft out a little and flex the pendula until they are exactly parallel with the frame. Make a record of your swing times, then swap the pendula over. Retime them, if the times stay the same the problem is with the pendula not the bearings. This is how i tracked down the my problem that the pendula shafts were not at exactly 90 degrees.
  • I started with the same as you 15 seconds, thinned the arbor, and polished it to a mirror finish, time when up to 30 seconds. Then a light bulb moment! My ball races were fitted straight from their delivery box and must have had a small amount of factory oil on then, cleaned their inside surface and 58 seconds!!!!
  • Hello all. I'm writing to share my experience with the elusive tick. I recently finished my sextus and could not, for the life of me, get the clock to run more that 90 seconds. I polished all the shafts and now the pendula each swing at 1 min.18 seconds. Together, they run 62 seconds.
    But, the clock would run exactly 90 seconds and stop.

    I have 3 kg. of weight and increasing to 4 kg still did not work. Now, what I found.
    The small pinion gear behind the escapement had a very small rough spot on one tooth and this would bind on the next gear, stopping the swing at each revolution. (Therefore the 90 seconds). I polished the teeth on the small pinion, and voila, the clock has been running now for 3 days. I had to add 6 grams of weight to bottom of each pendula to attain the 2 second swing time. I also have the weight set at 3 kg. So far, it is running fast 2 minutes per day. I am keeping a diary each day to log the accuracy. After about 2 weeks I will start adjusting to get better accuracy.
    I thought I would share my experiences so others can benefit.
    Dave, this is a great design, I love it.
  • My pendulums swing singly for more than 50 seconds. Not sure if they are exactly parallel. one seems a little off, but moving the weights seem to have no effect.
    Don't know if this is the problem though since when I add 2.9 kg of weight nothing happens at all. I swing the pendulum and they move for about five seconds and then no movement of any sort. No tick, no revolution no nothing. What am I doing wrong? Basically I have a clock that's accurate twice a day.