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Smiths Enfield Westminster mantel clock minute hand misaligned


Grandpa

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I have a working mantel clock which keeps reasonably good time and chimes correctly on each quarter (4,8,12,16). It also rings the correct hour at the right time.

Problem is that the chiming sequence always happens 7 minutes before the minute hand reaches the correct position.

Upon investigation and comparison with an identical (but non-working) movement it would appear that the steel minute hand arbor has been fitted into the brass hour-hand cog incorrectly, about 7 degrees out of square.  (Screwdriver as pointer in pic)

I cannot think of any solution other than to dismantle the movement completely, carefully tap out the steel arbor and refit correctly?? All advice welcomed!!

IMG_9139.JPG

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That's not necessary. The alignment of the star wheel on the cannon pinion has gone out of sync. The star wheel is friction fitted and should be able to rotate with some careful persuasion. By sighting it and trial and error, you can resync so that it triggers every quarter correctly. 

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34 minutes ago, HectorLooi said:

That's not necessary. The alignment of the star wheel on the cannon pinion has gone out of sync. The star wheel is friction fitted and should be able to rotate with some careful persuasion. By sighting it and trial and error, you can resync so that it triggers every quarter correctly. 

Thanks HL. I am new to this.  You mean if I grip that small cog firmly enough I should be able to twist the minute hand arbor inside it?? 

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Sounds like the center of the minute hand which in many is friction tight and it has moved which causes the chimes to be out of line with the dial.  you can repair this by putting the minute hand on a square file and move the hand center to the right place and then tighten the center with a few taps with a small hammer.  

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2 hours ago, Grandpa said:

Thanks to all. I'll have a go later today with a welding torch, lump hammer and a monkey wrench

 

Job done. Many thanks everybody. I can be a bear with very little brain sometimes and it took me a while to realise that the minute hand is constructed from two pieces of brass crimped together - the square drive collet and the pointer itself - and the easiest way of achieving what I wanted was to modify their positions relative to each other.

 

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