Bedside alarm clock keeps stopping.

[modeng2000Participant @modeng2000]

I have an old but valued family Polaris alarm clock that runs for around a short while and then stops. When restarted it runs for a few seconds and stops. This happens several times until it will go for a couple of minutes and then the same thing happens again. If the clock is placed face down it keeps running!

I have replaced the broken main spring and have rebushed one of the main spring pivofs. Nothing else has been changed, only giving the mechanism a clean.

Any ideas as to what may be wrong would be welcome please.

John

[modeng2000Participant @modeng2000]

[Michael GilliganParticipant @michaelgilligan61133]

John,

If it runs O.K. when face-down; that suggests that one or more of the higher-speed pivots on the backplate needs attention. [you are changing the loading on them by changing orientation]

My first thought: Start at the escapement, and work through all the wheels, checking for adequate "end-shake" … all the pivots should rattle between the plates … remember that, by engineering standards, things in a clock needs to be rather loose.

MichaelG.

[Phil PParticipant @philp]

You did remember to lubricate the new spring and all pivots after you cleaned the parts ?

Too much lubricant can be worse than none, please tell us you didn't use WD40 !! That stuff turns into green glue after a while.

Phil

[RICHARD GREEN 2Participant @richardgreen2]

Throw the alarm clock away, and get up about 10 o'clock……………….then tea and toast !

Richard.

[modeng2000Participant @modeng2000]

Michael, I have checked for all the high speed pivots being 'loose', there is axial movement and the new main spring bush is not tight on the spindle. I used to think of clocks as precision machines but they are quite different from model engineering! I'll look again at the pivots towards the balance wheel for the problem.

Phill, I did remember to lubricate the spring and pivots (second time around) and no I didn't use WD40.

Richard, While I appreciate your sentiments, as this was once Mother-in-law's I daren't throw it away!

John

[John Stevenson 1Participant @johnstevenson1]

Throw the innards away and fit a quartz movement.

[roy entwistleParticipant @royentwistle24699]

Check the balance wheel pivots and the cones they sit in If the cones show signs of wear they can be given half atturn both in the same direction and don't set them tooo tight

Roy

[modeng2000Participant @modeng2000]

John, the trouble with a quartz movement is that it can't ring the bell!

Roy, it might be the balance wheel pivots as the setting has been lost. I adjusted the balance pivots to what I thought was something like they were but could be wrong.

My mistake, I suppose, was not just replacing the main spring but going on to clean before reassembly.

John

[modeng2000Participant @modeng2000]

I've got to try to keep the old ticker going

[bobchaParticipant @bobcha]

Posted by John Stevenson on 28/09/2013 10:50:58:

Throw the innards away and fit a quartz movement.

John go and wash your mouth out you have no soul. But keep up your post.

[modeng2000Participant @modeng2000]

One of the pivots of the escape wheel had worn a small step on the spindle so the wheel assembly did not have free axial movement. I polished out the step and now the clock has a strong and steady tick. Many thanks to the replies which gave me the incentive to 'have another go' with an idea of what to look for.

Sorry to disappoint you John S, but I know what you mean!

John

Edited By modeng2000 on 30/09/2013 12:57:51

[BazyleParticipant @bazyle]

Posted by John Stevenson on 28/09/2013 10:50:58:

Throw the innards away and fit a quartz movement.

My schoolteacher neighbour sometimes acquires thow outs. I spotted a Synchronome clock in his garage and excitedly turned it round. .
Still I have tasked him with looking in cupboards at school to see if the master clock somehow survived.

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