Expert: Martin Meyer - 11/7/2008

Question
My wife inherited a vintage 1970's Colonial of Zeeland Grandfather clock which fails to fully chime on the quarter hour, half hour, three-quarter hour, and on the full hour, when the selection lever is in the Westminster position. We have not yet attempted to try any other selection. The chime mechanism will only chime a very soft sounding single note at each of these points. I can see the "music box" like drum turn as it chimes its single note. Then it stops turning until the next quarter hour. Otherwise, it seems to have no problem keeping good time, as well as perform its day and date functions. Unfortunately, the owners instruction manual didn't come with the clock, and I cannot find one on the internet. Are there any "do's" and "don'ts" to consider when dealing with this issue? I see a small adjustment like screwdriver hole located between the second hand dial and the month dial. What is the purpose of this adjustment? Thank you, Jim

Answer
Hi Jim,

Colonial used a variety of different movements in this period so, not knowing which movement is in your clock, I will have to answer your question somewhat generally.

There are two likely causes of the chiming problem that you describe. First, the pinwheel can be out of alignment with the chime hammers. Second, the chime hammers can be lifting and dropping, but not hitting the chime rods or tubes. If the first cause is your problem, when the clock attempts to chime you will be able to observe the pinwheel turning, but no hammer will lift except the one which makes the single note that you describe. If the second is the problem, you will see all the hammers lift one by one (4 at the 1st quarter, 8 at the half, 12 at the 3/4 hour, and 16 on the hour), but only the hammer that strikes the single note will actually contact the chime rods or tubes.

Regarding the first problem, you should try moving the chime selector lever back and forth through the different chime settings. This may cause the pinwheel to move into its correct position aligned with the hammers, and the clock should chime properly. If this doesn't help, then the pinwheel is incorrectly adjusted. It would be best to take the clock to a professional clock repairer in this case, as the pinwheel adjustment is quite exacting, and it would be possible to make the situation worse in an attempt to adjust it.

Regarding the second problem, this is caused either by the hammers being out of adjustment, or by the movement being out of position on the seatboard (the wood platform which the movement sits on). First, check that the movement is tight on the seatboard. Also look at the dial and see if it is centered inside the dial frame, or if it is off to one side. There are two long screws which come up through the seatboard and attach to the movement to hold it tight on the seatboard. Move the movement, if necessary, to center it on the seatboard, then tighten the mounting screws finger tight. They should be as tight as you can get them by hand, but do not use a pliers to tighten them further. If the movement is centered and tight on the seatboard, but the hammers still do not contact the chime rods or tubes when the lift and fall: if your movement is a "chime rod" movement (solid iron rods smaller around than a pencil) you can bend the hammer  shafts to move them closer to the chime rods. The correct at-rest clearance is 1/16" to 1/4". The hammer shafts are made of soft brass wire and can be carefully bent to adjust them. If your movement is a "tubular chime" movement (long hollow chrome or brass tubes bigger around than a broomstick), adjustment is much trickier. I would recommend having this adjustment done by a professional clock repairer.

Not knowing what movement you have, and not having the movement in front of me to examine, I am unable to tell what the screwdriver that you describe might be.  http://www.clockmasteronline.com