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The following is the transcript of a lecture offering details
concerning the inner workings of Clocks given before a meeting of the NAWCC #45941, which Tom has been a member of for over forty years. Tom represented London Clocks as a service representative for over 35 years. We are proud of our association with Tom and we thought this presentation would be of use to all who are interested in the technical aspect of clocks.

Gary Maples
Managing director London Clocks Ltd.

Helpful House Call Repairs

My name is Tom Scalzo, NAWCC #45941.  I’ve been a New York Chapter member almost 40 years. I did warranty house calls for the major clock companies. At present I am associated only with London Clocks Ltd. I got involved with house calls when the Clock companies had asked if any collectors would be interested in doing house call repairs. I took up the challenge and have been at it ever since.

To get started, when someone calls for a repair, I ask them what the problem is. Usually the response is "clock runs and stops," strikes the wrong hour, doesn't keep good time, "chimes either run slow or don't run at all." At times they'll say "clock keeps chiming and won't stop." Frequently they'll say "we moved the clock to a new location and it won't run. The center weight and chain fell off. Pendulum fell down and the "little thing' broke. These are some of the problems they'll come up with.

Determining the problem:

OK; now down to business. Some or all of the questions I ask are:
How old is the clock?
What make is it?
When was it serviced last?
Tubes or rods?
Chain or cable?
Was clock moved recently and now won't run?
Does the clock need to be set up as well as repair and serviced? They probably don't know. I have to use my own intuition.
Last: is there parking nearby?

Diagnosing and observation:

Before doing anything, look at glass on door for tiny scratch where the minute hand tip may have been rubbing. Is clock hooked to wall? Children have pulled clock down.

Open the door, does the door close by itself? If it does or if it stays open, it's an indication that the clock is not level and will have to be corrected later in the service call as the cabinet may have to be lain down to adjust feet if levelers are frozen, they usually are.

Finding the problem or problems:

Check for audible click when rotating minute hand backwards.
Check that the weights are in the right position.
Check the saddle anchors if loose.
Check the hour and minute hands for clearance (jiggle). Is the second hand opening clear?
Check slide of canon pipe - loose? Tight?
Check moon dial detent; is it binding.
Some moon dials have plastic wheels and are notorious for wobbling & binding the canon pipe.
Check crutch pin. Is it in the suspension rod slot?
Check crutch foot slot for choking.
Is the suspension spring OK? Look carefully one strap may be broken. Spring should be snug and not tight.
Is the verge the old friction type or the modern self-adjusting type.
It just enough to give a better swing of the pendulum.
If movement locks at about 5 minutes before the hour, problem may be sluggish levers causing warning catch lever to stop the warning pin to clear and run. Also make sure the hands are not touching at this point.
Always study at home what makes the 1/4 hour warn, run and stop.

Does the pendulum wobble? If so, one reason is the foot of the crutch is not truly perpendicular to the movement and the suspension spring too soft or too long.
Are there glass shelves to interfere with the swing of the pendulum?
Is there a light inside that may dry out the oil? Is the clock next to a radiator or in sunlight?

To further your examination of the movement, remove the weights and check the arbors for end shake. While the pivots are free, put a drop of the finest machine oil available in each pivot, shake the gear back and forth and using a small stiff brush, remove any sludge that may come loose; now is the time to check for worn bushings. If you don't foresee any problems, give each bushing a light coat of oil to replace the center weight chain, assuming clock has side doors, if not, go thru the roof if possible and make use of 2 wires to pull chain up and through. Examine chain for linkage spread (banging weights up into the saddle).

To replace the center weight chain, assuming clock has side doors, if not, go thru the roof if possible and make use of 2 wires to pull chain up and through. Examine chain for linkage spread *banging weights up into the saddle).

Replace the center weight (with the pendulum off) and if the suspension rod flutters, then for all intents and purposes, the clock should be free to go. Replace the left and right weights. Advance the minute hand to chime and listen for a clean sound with 'after tone.' The hammers should have at least 1/16 of clearance. If not, bend the wire and listen. If during the chiming, one or two notes don't make a sound, it may be the music drum activating points are worn and not pushing the hammer rocker arm. Using needle nose pliers, bend the point slightly to come in contact with the rocker arm. If after testing chime sequence, the quarter hours are out of synch, move the minute hand to the first quarter to chime 4 notes then rotate the music drum by loosening the large drive gear to the drum until you hear the first proper quarter. If for any reason you think the music should be running a little faster, using you needle nose pliers, give a slight bend to the end of the fly fan as to make it fan the air a little less.

Finally, if everything seems to be working ok, test the clock by placing the minute hand a few minutes before the hour and if the clock chimes, try it once more, the reason for doing this is to see if the movement has enough power to move through the chiming levers.

On cable driven movements, pay close attention to the center cable spool for tangles. If the cable appears to be tangled, then other than removing the movement to the customer's table or to your work shop, consider another choice. If the back panel of the cabinet is removable, and if possible, remove the verge plate and verge but before doing so remove the center weight. Pull on the cable strongly and most times the cable will start to run free. If not, then the job has to be done on the bench. Unfortunately this makes for a big job especially if it is a 5 ore 9 tube clock.

Old German 'round top' clocks that are hour & half hour, Bim Bam, and Westminster are usually made so that the movement just slides out for examination and service.

Additional notes:

Tool Kit Contents:

Usual screw drivers, pliers, tweezers,
small hammer, brushes, etc.
Clock oil, quality machine oil, grease
Forked screw driver, and slotted hook
Special pin pliers
Special broken pin pusher
Assorted parts compartment boxes
Assorted hands and cables
Door key and windup master key
Let down dowel
Bench block
Wires, shims, c-clamp
Cutting & smooth broaches
REamer, flash light & extra batteries
Electric screwdriver, chuck & drills
Scale, double sided tape, glue,
Dentist's mirror
Vise in car
Center punch and nail set


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