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August 12, 2018 at 8:02 pm #50084
I am a beginner, taking clock repair classes at a tech college. Over the summer, I’ve been testing a Gilbert bim-bam mantle clock I repaired last class. On what seems a random basis, the first tone “bim” has an extended vibration, as if the hammer is striking the rod while the rod is still vibrating from the previous strike. The result is an echo of the bim rather than a clear tone. The extended vibration hasn’t occurred with the “bam.” Sometimes, it vibrates correctly, and both chimes are clear tones.
I am not seeking perfection with this clock, just want to understand what’s going on, regardless of whether it’s repairable. I have tightened the chime rods, fussed with the hammer height, and it still happens randomly. Any comments or advice is welcome. See photo taken prior to repair/cleaning. Thank you.August 13, 2018 at 12:24 pm #64926c.kellyParticipant
I read this earlier this morning but have just now had time to reply. If the unusual vibration is on the first bim then the wheel that lifts the hammers may be slightly out of position. By that I mean the star may be lifting the bim hammer a bit after the strike has completed. That would mean when the next hour strikes that hammer might have a different sound-maybe because it produced a bit of drag on the wheel as the strike train started up. This would only have an effect on the first bim and after that the sound should be normal.
Another thing to possibly think about is the chime rods themselves. I just repaired an old clock that would randomly stop. It had two chime rods and the longer one would sometime rub against the pendulum bob. Turned out the rod was weak and would wobble around, moving as much as a half inch so that it would sometimes contact the bob but not always.
One other thing to check might be the star wheel that trips the hammers. One of the stars may be worn or bent not lifting the hammer up as much as the others but the should have an effect on both bim and bam.
Don’t know if any of these ideas help but thought I would throw them out there.
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