OT: chiming clocks

[Scott]

Another mad question for the Covid -19 era:

We were discussing ... Is it possible to build a mechanical clock that does not chime through the night?

[spuorgelgoog]

Yes, manual or automatic night silence is a fairly standard feature.

The Kieninger movements in Clocks & Chimes clocks have automatic night shut-off between 10:00 P.M. and 7:15 A.M. (for quarter hour strike movements) or 10:00 P.M. and 7:00 A.M. (for half hour strike movements) If your clock does not strike or chime during the daytime, its movement is in the night cycle. You need to move the clock hands back 12 hours to go into the day cycle. Owain

[Max Demian]

Quite a lot have a lever that silences the striking/chiming [1] mechanism. Usually you still have to wind up the other spring(s)/weight(s) as it has to "go through the motions" but silently.

[1] "Striking" means counting the hours, and sometimes striking a single note at the half hours. "Chiming" means playing a tune, such as the Westminster chimes of the Great Clock. Big Ben does the striking.

[ss]

The hammers that strike the `gong` are mechanically raised then fall down to gong, some have a lever that when pulled back then it prevents the hammers falling down to strike the mechanism, hence no `gong`

To have it done automatically would be possible but would be a more intricate mechanism.

[Nick Odell]

My brother in law collects clocks and some of his have movements which can be switched so the clock stays silent at night. I guess those movements can be bought or, if you were planning to make your own movement, that element of the mechanism can be made.

Nick

[Brian Gaff (Sofa)]

Yes. Oh you want to know how. Well, my grandmother had one like that. It was purely mechanical and simply had a couple of cams inside that effectively kept the bit that moved the clapper out of the way of the little escarpment thingy, I'm sure it has a name, for the time between two set by trial and error on a couple of knobs inside the back of it. I was actually intrigued by this clock as it had no bells, the ringing seemed to be done by some tuned springs inside the back. Not being homologically inclined, I know no more. Apparently it was often done on cuckoo clocks too. Those damned things annoyed me. Brian

[Brian Gaff (Sofa)]

Talking of mechanical things. What is this device. Witnessed in the 80s in a Guernsey shop. A large piece of furniture, a bit like a wardrobe but thicker at the bottom and stepped. All panels were bevelled glass. Inside the top part a big disc, like a giant one of those music box discs mounted vertically ran on a mechanism branded Thorens. It played tunes, a little plinky plonky like abut one could change the discs to get a different tune. Not for sale it said on a sign!

Brian

[newshound]

IIRC on one of my clocks, some years ago, although it did not have a "switch" you could just open the back, flip the hammer away from the chime and it would rest back on the case and not chime. You still had the clatter of the mechanism as it operated the cams.

[NY]

A lot of chiming clocks use tuned bars (effectively one leg of a tuning fork) rather than bells like a bicycle bell. I've not come across ones that use tuned springs.

That reminds me, I have three granddaughter clocks (about 4 feet high) that were my grandparents'. One of them is decorated with Chinese or Japanese scenes - not my thing at all, but my wife likes it so she can have it in her study. They are in various states of repair, in that they all run, but some only for a few seconds and others for many hours - but all stop eventually, long before the spring has wound down. The one that runs for longest has a "limping tick" - ie the interval between the tick and the tock is longer than between the tock and the tick - and that's after checking that the clock is level and that the pendulum naturally hangs vertical when the clock is stopped.

You've reminded me that I need to find a clock-repair shop and get them all looked at.

[newshound]

On clocks with a single tone the "chime" is often a flat helix, free at one end. Some would describe that as a "spring".

[Dave W]

It's a Polyphon.

[Davidm]

I remember seeing and hearing one a few years ago at an NT property on the south west coast somewhere (Falmouth way I think).

[ss]

You can make mechanical adjustments to correct that but an easier way is by simply using a wedge under the clock on one side (forget if the case is level) until you get an even `tick tock`

It is quite easy to adjust the internals to get both the case and the mechanism level if you know how but easier just to use wedge or folded piece of paper.

I suspect the others just need some small adjustments and the pivots oiled.

[Max Demian]

It's usually a bad idea to oil the bearings of a clock as they rely on surface tension to keep the oil in. If you put too much in, it will attract dust or gravity may pull the oil out, leaving you with a dry bearing. The mechanism should be disassembled and cleaned with an organic solvent, reassembled and the right amount of the right kind of oil applied. Otherwise it's better to leave alone.

[PeterC]

I did that to a 7-day chiming mantleshelf clock. Studied it carefully so that I coud see how it was assembled and also how it worked - understanding that can be useful! Cleaned it and oiled all bearing surfaces, rubbing/meshing parts with Quadrilene non-volatile instrument oil. Got it rebuilt, tried to get it going tick-tick or tock-tock, not tick-tock and it wouldn't run for very long. Had a close look and found that the gears were binding just a tad - all of the bearing holes in the plates were slightly pear-shaped and it had been the gunge keeping it just about going. Can't remember what happened to it. Pity, 'cos some years lter I got to know an horologist... (he was a proper one - could actully make a clock or watch).