I'm a Newbie, and am retired so have time for projects, and am helping a friend trying to get their Urgos 6/36A mantle clock running. I've taken the movement out of the cabinet, and it all looks good. Nothing apparently broken. It will chime properly when you turn the dial at each quarter hour, half hour and hour and chime the correct hour. But it doesn't run. The area at the top that is silver colored and is where the "ticker" is, looks fine, the spring is intact, but only ticks for a few times before stopping. I was able to properly release all the tension on all 3 of the springs. I then wound them back up. Two of them wound up find, but the 3rd one which controls the strike mechanism for the chime won't lock into position and hold the spring. It appears that the flat piece of metal that applies tension to keep the lock on the gears isn't providing any tension/pressure to keep it "locked" into place. I'm attaching a photo.
So 2 questions: (1) would this affect the clock's ability to run at all, and (2) where can I get a replacement part. It looks rusty and maybe that's affecting its tension. Thanks.
Hi there wsscott,
Firstly, I am not an experienced clockmaker, just a tinkerer, much like yourself. I have been tinkering for a few years and managed to get a few clocks working, so, I am not a total newbie. There will be others much more qualified than I who will be able to give you much more comprehensive advice. But until they come along (possibly after the moderator moves this thread to the correct area??), I will tell you what I know, just so that you do not get the feeling that you are being ignored.
The "flat piece of metal" is called a "Click Spring" and it is definitely bent out of position. It may be able to be bent back so. that it applies the right pressure to the "Click pawl" to keep it engaged and stop the main spring unwinding. It should be pressing against the click pawl with a similar pressure as the corresponding click springs on the other two main springs (time and chime)
The most usual reason for a clock to stop is because of wear between the pivots (that is, the axles of the cogs, or "wheels" as clockmakers call them) and the bearing surfaces (that is, the holes drilled in the plates that the pivots revolve in. Clockmakers tend to call these bearing holes "Bushes", although, I guess it is not really a bush until the original worn hole has been drilled out and replaced with a "bushing" of the correct size). What happens is that, because of the high lateral force on the turning pivot, the bearing holes wear and become elongated, rather than perfectly round. This changes the distance between adjacent wheels so that instead of simple meshing together with nearly zero friction, the wheels actually push hard against each other creating a lot of friction which eventually stops the clock.
The photo that you provided shows a pivot in a bearing which appears to have a little bit of black grease in it. I don't think that is a place where I would expect to see grease! Check all the pivot holes and see if you can see signs of black grease or crud. This can be a sign of wear. What happens is that as the bearing wears, tiny flakes of brass, oxidise (black) and combine with the oil (which is used rather than grease) to form a grinding paste, which accelerates the wear of the bearing.
Be very careful releasing the tension on the mainsprings!! If they go off quickly (with a bang!) they can ruin the clock. (bending pivots, stripping teeth from wheels, etc). I have a 6 inch length of broom handle, which I have drilled and slotted so that it neatly accepts the clock key in the end of it. Using that, I can very slowly release the tension on the click and then, holding the click out slightly clear of the ratchet, I can VERY SLOWLY allow the springs to unwind, while holding the broom stick/key firmly with my hand.
Once the main springs are fully unwound, then move the wheel NEXT to the main spring barrel back and forth, looking for movement of the pivots within their bearing holes. There should be very little to no sideways movement of the pivots within the bearing holes. If you can see noticeable movement, that indicates significant wear and that bearing will need to be drilled out and re-bushed, to return the wheel to its original position.
If you do all that, at least you will know for sure why the clock has stopped!
The next step is to completely dismantle and clean the clock, polish all the pivots to a mirror finish re-bush all the worn bearing holes, reassemble and oil the movement with proper clock oil and it should then work.
There are many threads that deal comprehensively with all these topics elsewhere on this forum.
For more good information, go to the FORUMS section (at the top of your screen) and find the forum called "Clock Repair", then "How to do it Articles", then look for "Chime Clock Basics", "Bushing Using Hand Tools", "Reassembling a Clock Movement", and "Clock Repair Tools". Also go to "Hints and How-To's". Look for threads like ""Clock Parts Terminology". I hope this helps. There is plenty of reading that you can do while you ar waiting for the experts to turn up.
Remember, you are retired. You have plenty of time. Don't rush into it and break the clock by not doing it the right way!
Best of luck
Walesey
