Refurbishing a Romanian clock

[utzelu]

Hi,

I recently got a small vintage clock from my father in law. It is an Aradora clock, fabricated in Romania in 1978. I guess the movement was made "in house" as there is no marking on it.

I wanted to refurbish it a little, so I disassembled and cleaned it. So far so good, but the issue I currently have is that I cannot figure it out how to lock the mainspring on its wheel when reassembling the movement. I am able to wind the mainspring all the way, with the help of a custom fabricated jig. The problem is that space available in the movement is so restricted, that no spring containment ring fits inside. I wonder if anyone has any idea about how the mainspring could be fitted back.

Thanks,

DanP

[clockboy]

I have used a cable tie in the past which gives more room for assembly.

[utzelu]

Before I made the winder jig I have tried the cable tie, but it was too thick. I guess I will try to machine another containment ring, even smaller in diameter.

[jdm]

I think a strip of thin metal (just like a mainspring) would work, with the ends bent to link to each other in a loop. Being flexible would go around the hook and adapt to the shape.

Edited October 13, 2017 by jdm

[oldhippy]

The easy way is to just unwind the spring, the end goes over the post, hook the other end over the arbor and with the winding key start to wind it up making sure the end over the arbor is being wound on. Before you start to wind make sure you have all the wheels in place and both plates tightened up.  

[utzelu]

Somehow I think the ring should be open ended, since the mainspring has a loop end that hooked to the post on the winder. Not sure how the thin metal strip linked on the ends (basically a closed ring) would be placed on the mainspring.

[utzelu]

5 hours ago, oldhippy said:

The easy way is to just unwind the spring, the end goes over the post, hook the other end over the arbor and with the winding key start to wind it up making sure the end over the arbor is being wound on. Before you start to wind make sure you have all the wheels in place and both plates tightened up.  

 

BINGO! That's how it is done It takes quite a bit of fiddling to get the mainspring inside but it is working.

Thanks a lot!

DanP

[utzelu]

I managed to put the movement back together and it is running. That was a good feeling, hearing the tick-tack rhythm. For the time being it runs without hands and I haven't mounted it inside the case. The thing is, the watch stops running after about 14 hours, though I would expect it to run for about 24 to 30 hours. Winding the mainspring back to max. actually needs maybe 2 full key turns. So it looks to me that there should be some more spring left after 14 hours.

Anything I should check in particular? 

The mainspring is 3.5 mm x 0.35 mm, though I haven't measured the length.

Thank you,
DanP

[oldhippy]

10 hours ago, utzelu said:

I managed to put the movement back together and it is running. That was a good feeling, hearing the tick-tack rhythm. For the time being it runs without hands and I haven't mounted it inside the case. The thing is, the watch stops running after about 14 hours, though I would expect it to run for about 24 to 30 hours. Winding the mainspring back to max. actually needs maybe 2 full key turns. So it looks to me that there should be some more spring left after 14 hours.

Anything I should check in particular? 

The mainspring is 3.5 mm x 0.35 mm, though I haven't measured the length.

Thank you,
DanP

This has all the signs the m/spring is the wrong one. It should last for 30 hours; it should take a lot more than two winds, it is the wrong length.

[utzelu]

35 minutes ago, oldhippy said:

This has all the signs the m/spring is the wrong one. It should last for 30 hours; it should take a lot more than two winds, it is the wrong length.

 

I was thinking about it too, but some doubts do come up in my mind: the clock belongs to my father-in-law and he says it was never serviced nor opened. It wasn't used for maybe 15 years but he remembers he was winding it every day when it was running. That tells me the power reserve was over 24 hours at some point in its past. Moreover, I noticed, that when I wind it up, the balance wheel doesn't turn by itself - I need to push start it for the clock to start running.

Could it be that the m/spring has degraded by not running for so long, or due to my handling when working on it?

Thanks,

DanP

[oldhippy]

First of all about the clock starting, the impulse pin should be in the centre of the pallets when it isn’t moving, this will make sure it has an even tick. To get a good action the balance tips should look like a sharpened pencil, the oil cups should be clean with no indentation; wear in these will cause poor action. If you have a lathe, you can sharpen the staff.

 

 I have only come across m/springs being worn or losing their strength when being used, never heard or come across one when it is idle.  I suppose if it is made of poor metal that could cause the problem. The handling of the spring hasn’t caused this.  

[utzelu]

Hi again,

I am resurrecting this thread after a long idle time. After struggling to keep the watch running, I abandoned the project and moved on. But now I am thinking to restart working on it. So far I am kind of sure the hairspring is damaged, as I managed to warp it. I won't attend to repair it but instead I am thinking to purchase another hairspring. The clock movement being old and obscure, I have no idea about the hairspring specification. I see Cousins UK sells a set of hairsprings assortment and was thinking if it would be suitable to go on this route. I have big holes in my watchmaking knowledge and I am not sure if there is a correlation between the hairspring and the rest of the train gear and how to choose a new hairspring. So I am very eager to get educated on this matter.

[oldhippy]

You need the thickness of the hair spring, the coils need to be about the same and do not forget the collet for size. 

[clockboy]

Agree with oldhippy it is not easy to find a replacement. Have lots and lots of hairsprings purchased over the years and yet time & time again I never have the correct replacement.

[utzelu]

Thanks for the advice. Will have to disassemble the movement again and check the hairspring closer.