Expert: John Newman - 7/31/2010

Question
QUESTION: My Grandfather built a emporer clock kit with a viking series 133 movement it runs well but gains five minutes a day. i have adjusted the knob on the end of the pendulam bob to its lowest but it still runs consistently fast. i have all original manuals but see nothing in the way of a toubleshoot for this any suggestions? it was built in 1977
thanks in advance

ANSWER: John, interesting tat you find a Viking movement in an Emperor clock.  Emperor was in Fairhope, Alabama and Viking was in Foley, a few miles away.  The adjustment of the rating nut should change the speed of the clock.  Here's what could be happening.  At all times the bottom of the bob should be firmly in contact with the rating nut.  Friction sometimes causes the bob to remain stationary even though the nut is adjusted down.  If the nut has been lowered and the bob is still in the same position, do not move the bob yet.  Carefully screw the nut back up until it comes in contact with the bob.  Using a quartz or accurate timepiece, set the clock to the correct time and start it.  Run it for 24 hours and note the error, as you say, 5 minutes fast in the 24 hour period.  The adjustment for a floor clock is around one minute a day per 2 complete turns of the rating nut.  So the amount of adjustment for 5 minutes a day would be to unscrew the rating nut 10 complete turns.  Then carefully pull the bob down until it comes in contact with the rating nut.  Reset the time and run it for another 24 hours.  If it still runs a little fast, unscrew the nut proportionally to the previous adjustment and time again.  If you have over adjusted and it runs a little slow, tighten the nut a little to speed it up a little.  You will probably have to repeat the adjustments a few times to get it close.  Up to a few minutes a week is usually acceptable for mechanical clocks.  I hope this works.  Let me know how it goes and if you cannot make the adjustment, there might be another problem.


John Newman
THE VILLAGE CLOCKSMITH
Old Prattvillage
Prattville, Alabama
 

---------- FOLLOW-UP ----------

QUESTION: john
i tried the adjustment you suggested making sure the bob was snug against the adjusting nut starting up high 20 turns from bottom after three days of adjusting five turns at a time i ended up at the very bottom again still running five minutes fast every 24 hours don't want to be a pest but do you have any other suggestions that might help I'd be happy to get it down to a minute a day after all it is only a sentimental piece. but we sure have enjoyed telling people my grandfather built it. Thanks in advance.

ANSWER: John, your questions are not a bother. We will keep at this  until we get it resolved.  Other than being a pendulum length issue, about the only other cause could be a problem with the escapement.  If the verge pawls (the part that actually makes the tick tock sound) are out of adjustment, the escape wheel teeth can be skipping.  If this is happening, you could probably hear it if you listened closely.  Normally you should hear a good clear tick tock.  Skipping will alter that sound so it is definitely detectable.  It would take an experienced clockmaker to adjust this. But let's focus on the pendulum. How long has the clock run fast?  Was it an abrupt change, and if so, when was the change?  I have found some clocks with the incorrect pendulum attached.  What I would do is time the clock with the rating nut all the way down.  Time it for 12 hours against an accurate quartz clock or watch with a seconds hand.   Then run the rating nut all the way up, reset the time and repeat the procedure for another 12 hours.  Let me know the results of both tests.

John Newman          

---------- FOLLOW-UP ----------

QUESTION: John i ran the test you suggested with the adjustment  nut all the way down it ran exactly three minutes fast in a 12 hr span. Then with the adjustment nut all the way up it ran 14 minutes and 30 seconds fast in a 12 hr span also with the adjustment nut all the way up the edge of the pendulum bob slightly bumped the side of the cabinet so at the end of the test i stopped the clock until i hear back from you thanks again.
john wood

Answer
John, it could be that you have the incorrect pendulum on the clock.  If the bob is larger than an original one, that could cause the bumping on the side.  There is a way of correcting the problem with the pendulum you have.  I would run the rating nut up about 3/4" and add weight to the BOTTOM of the pendulum.  I do this by adding BB's (or large buckshot) through the slot in the top back of the pendulum bob.  I would put about 100 in and time it.  Go from there and keep adding or subtracting until it is close to the correct rate.  You can then find tune it with the rating nut.  Also, with the added weight the bob will probably not hit the side of the clock case.  If you remove the pendulum you will have to take care to keep the BB's from falling out when it is put down.  I have a way of actually gluing the BB's after I have chosen the correct amount.  Or you can obtain a new pendulum or extend the existing one depending on how handy you are.  If you decide to go that way, I will explain how I do that.

John Newman
THE VILLAGE CLOCKSMITH
Old Prattvillage
Prattville, Alabama