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Query about an Enfield Westminster mantel clock


Rixy

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I have cleaned and reassembled an Enfield Westminster (1934 date on the clock). When I wind the minute hand to the o'clock, the long pin on the time wheel raises the long flirt and puts both the chime and the strike in warning (the rack drops to the snail). When the chime starts, the 'bump' on the chime plate lifts the flirt again and moves the lever over the gathering pallet a second time. Should this happen? Seems unnecessary for the lever to move twice. Hope I have made my query clear and used the correct vocabulary.  Have included some photos. 

All suggestions welcome!

 

20230301_192607.jpg

20230301_192628.jpg

20230301_192637.jpg

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With this movement and nearly all clock movements that have chime and strike and powered by springs you have what is called the warning. So just before the clock chimes it goes into the warning, then it will chime on the quarter past, the half hour , the three quarter then the hour. That is the chiming action. The strike side will do the same for the half hour then the hour, on the hour it will strike the hours. One thing to look out for is when it goes into the warning no matter if its the chimes or the strike the hammers should never lift, they should only lift for chiming, the same goes for strike.  

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Thanks for the advice. Have checked and the hammers are working properly (not lifting when they shouldn't).  I have read that the long pin (out of the four on the time wheel) is to release the self-correct lock. It does that and also lifts the L shaped lever on the strike side (the one that releases the strike rack) so both the chime and the strike are in warning. The chime and the strike then work correctly so I am uncertain why there is a bump on the chime plate. I think it's all to do with the self correct system. It doesn't seem to affect the running. 

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I'm not sure what you mean by the chime plate. With clocks and certainly with chime and strike works make sure you oil all the posts that the levers fix onto, where levers touch you should also but use clock grease because that will not run. The same goes for wheels that have pins and certainly the hammer ends that touch wheels or pins.  

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Hello Rixey  find attached the book, Chiming clocks is explained on page 132 with drawings. probably better than I could relate, hope it helps and it will give you the part names and the workings.    cheers

Handbook_of_Watch_and_Clock_Repairs.pdf

Hello Rixey  find attached the book, Chiming clocks is explained on page 132 with drawings. probably better than I could relate, hope it helps and it will give you the part names and the workings.    cheers

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Thank you so much watchweasol! The section on chimes was really helpful and I realise now that when I wrote 'chime plate' it should be 'chime locking plate'.

Still not sure why the long pin on the star wheel lifts the flirt so high it puts the strike ready (as well as lifting the self correct detent) so that the bump on the chime locking plate is redundant, but the book looks like it will give me more insight.

Have a good evening.  Cheers.

 

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Hi my interpretation for what is worth is that the long arm on the center wheel releases the hour strike

into warning the hump on the chime locking plate then releases the ths warning allowing the movement to run the sequence after which it’s then set up got the 1/4 chime being the next cutout for the lever to drop in. And release the 1/4 strike and then repeats for the 1/2 and 3/4.  The self correction is reset at the 3/4

Hi just a thought when the rack drops where about on the snail can does it come to rest, it should be half way on the cam slope.  Did you remove the center cam on dismantling ? It may be on wrong in relation to the chime locking cam

 

 

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Hi there. I did take the snail off when I dismantled the mechanism. I put it on so the rack falls at the start of the slope (beside the 'step' of the previous hour). I'll move it round a notch or two to see if that makes a difference. 

The strike starts when the detent drops into the dip on the chime locking plate, quite a way after the bump.

Another problem I realise I now have is that the going train keeps stopping and the escape wheel refuses to budge even if I rock the pendulum arm. If I give the wheel before the escape wheel a nudge it will run again but only gor a few minutes. Do you think I may have damaged the pivots when reassembling?

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Hi judging by the symptoms you describe it’s a possibility. One way to check is to remove power fron the clock , remove the pallets then put a wind on the train, if the escape wheel does not move you need to check out thr freedom/ pivots. If the problem persists install only the going train and recheck, a bit of a bother I know but each train is an individual entity interlinked via the front plate levers etc.

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When it comes to the snail  for it to fall correctly for 12 it should have good clearance, so when it comes to 1 it should be about a third on the shoulder  of the snail. If you test it from 12 until 3 all the rest should be correct. With this movement you can remove the barrels without taking the movement to pieces, so I would remove the barrels which will give you a better view to see if you can spot the reason the power gets jammed, as watchweasol says removing the pallets will also help.   

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Hi one or two attachments which may help a bit with the terminology.

Mulling it over a simple way of explaining it is that the long arm on the center cam sets up the warning for the strike and the hump on the chime cam releases the strike after the chime has taken place the long lever drops into the slot releasing the strike from its warning lock. basicaly the hump holds the long lever in its warning state waiting for the four rounds of the chime.

front plate chiming clock.jpg

Snail Divisions.jpg

Urgos chime mvt front.jpg

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I finally seem to have it all working! Took the side springs out and the pallet off, as suggested, to get a better look. The arbor for the third time wheel was slightly bent, so I gently levered it straight(er) - just a touch. I oiled the pivots and it has been running for three days now. Have also lined up the snail as it should be.

For the chime and strike problem, fortunately I had another Smiths with a similar movement (it works and just needs cleaning) and compared the two side by side. When the long lever was raised by the long pin on the first (problem) clock it was lifting the rack hook a tiny bit too much, which is why the rack was dropping early. I adjusted the 'tab' (the bit that connects with the rack hook) on the long lever downwards with pliers, just about 1mm, and that made the difference.  Now the long pin releases the auto correct and puts the chime into warning, while the bump on the chime locking plate causes the rack to drop as it should. Yeay!

Now I can clean up the case and get it all back together. Thanks for all you help and advice OH and Watchweasol.

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