Clocks, Watches/Grandfather clock chimes erratically
QUESTION: I have inherited a clock made by a family member.
It has a 3 weight, cable driven, triple chime Kieninger MSU13, no (0) jewel unadjusted movement from 1981, as far as I can tell.
Serial number is 81 K 116cm 26,9-8. The 26, 9-8 is a sticker applied to the back plate.
It was crated and has been shipped twice in the past 5 years. I do not know how it was handled. It was on its back for an extended period of time.
It was set up about a year ago and after some trial and error I got it in beat and it has kept very good time.
However, about 6 months ago it started chiming erratically, sometimes the correct number for the hour but many times only 1 chime. I purchased a cleaning kit online, removed and cleaned & oiled the movement per the instructions provided.
It seemed to chime correctly for a few weeks, however the chime weight was never all the way down at the time of winding.
It seems like the adjustment for the mechanism that releases the rack for chiming has shifted somehow. The snail seems to be positioned properly.
The lower armature that deals with ¼ hour appears to work properly.
The upper armature that releases the rack never seems to get enough lift to allow the pin to clear the rack. (Please see photo)
Is this an adjustment problem or has the movement worn in a way that would require replacement?
Thanks in advance for you help.
ANSWER: Brad, you are correct in your analysis. The way this works is that there is a star cam on the minute arbor behind the snail. It has 4 points. Three of the points actuate the lifting arm to start the chime but the forth point sets up the chime and strike sequence. The forth point is higher and has to do with the strike. As the chime locking cam (on the right side of the movement) rotates on the hour it progressively lifts the strike lever. That lever has two functions. It releases the strike locking wheel in a "warning" mode which is like cocking a gun prior to firing. This is done with the tab on the lever that goes through a hole in the plate and engages the warning wheel stop pin. When it is lifted it is now ready to strike. The second function is to lift the rack hook to allow the rack to drop to the number of teeth to strike the correct hour. When the lever drops into the slot in the chime locking cam, the chime stops and the strike starts. As you stated, the pin on the rack hook is not lifting enough. The lower part of the strike lever that rides on the chime locking cam can be adjusted (slightly spread)so the upper part of the arm (with the pin at the end) lifts enough for the pin to clear the rack. The reason I explained the two functions of the lever is that when the lever is formed to clear the rack, the warning function can be affected. It has to be a precision adjustment. This adjustment also affects the way the chime lift lever lifts the strike lever. Sometimes the mechanisms have to be readjusted, as they are interdependent of each other. I will have to say that there might be other causes, such as wear, but let's just concentrate on the lift lever right now. Let me know what you find.
THE VILLAGE CLOCKSMITH
---------- FOLLOW-UP ----------
QUESTION: I will try to adjust the armature as suggested. There is also an idler arm that is attached to the shaft that the upper armature pivots on. It is attached via brass fitting at the end and has a set screw to position it on the shaft. Can this be adjusted for lift for the strike? I have a picture of the armature in question. How can I send a copy to you for review.
Brad, I am sure the screw adjustment on the lift arm will not affect the lift, only the position, which would take another function out of adjustment. But send me the photos. My shop email address is below.
THE VILLAGE CLOCKSMITH
(Due to the number of Allexperts questions and
the workload I have at my clock shop, I regret
that I cannot answer personal email questions on a timely basis
other than Allexperts follow ups.)