First attempt at an English Westminster chime movement

[Beagle2]

Hello,

I’m rebuilding my first Westminster chime clock. It’s made by Arlanza and goes in a Napoleon’s hat mantle piece case. 
 

Unfortunately, I’m having great difficulty in getting the chime to trigger each quarter.  

The Westminster chime triggers roughly every 5 or 10 minutes. The hour strike also seems to be sporadic as to when it occurs.  
 

My question: 

There is a switch on the face, which if pushed down will stop the clock from chiming. 
 

Pulling the lever down rotates an axle (green line). This lifts a lever (blue arrow) which blocks a pin (red arrow) on a gear wheel, thereby stopping the chime. 
 

Is this mechanism purely to turn the chime on and off when wanted? 
 

Or is it somehow involved with how the chime  is triggered each quarter, and hence needs adjusting? (Screw setting)

[oldhippy]

That lever is for silent or strike. You have to make sure you have the wheels in the correct position both chime and strike in order for the chimes and strike to work. Also the cam wheel on the chime the gathering pallet on the strike. If you need help with this movement I can help you through it, just ask.  

[watchweasol]

Hi  Just follow Old Hippy's advise snd you will be ok.  Two good books on the subject of clocks are "Clock Repairers Manual " by Mike Watters and  "The Clock Repairers Handbook" by Laurie Pennman.

[Beagle2]

Hello,

Thank you both for these pointers. 
 

I did not disturb the position of the gathering pallet so am hoping it is set correctly (?). 
 

When triggered the rack seems to drop ok so am hoping the strike is alright.... although may well be wrong. 
 

The issue seems to be that the chime triggers approximately twice every quarter hour. And sometimes it runs for several segments of the notched chime cam wheel (not sure if correct term). 
 

There is some form of pretension device (?) on the back of this cam wheel. I’m not sure what it’s meant to do? (Red circle)

I’ve just ordered the Penman book, Watters had 2 month wait. 
 

Any more  pointers greatly received. 
 

 

[oldhippy]

What you are describing sounds like the chime side is what is called tripping, this can be caused by the wheels with pins in them and the chiming levers not correctly working together. Remove the cam wheel, take the hands round and see if each time the chime lifts the leavers and the chime works. Each of the 4 hammers should life once and drop. 

The cam wheel with the spring is a device that if for some reason the chimes and the hands got out of synchronization it will act and put it back in correct order, it works in a way when the levers lift at the quarter it will not trigger the chime until it is all in line. 
Please do this first and then get back to me. 
 

[Orologi67]

So you took the movement apart and reassembled it?  There are two main ways a chime side mechanism stops. From your picture of the front plate i believe you have the below description.

One is by a pin on the 3rd wheel.  This pin will come in contact with a prong projecting from a lever (either outside or inside the movement) that also runs along the edge of the chime cam or chime countwheel.  When the lever comes to an indentation in the countwheel it will lower just enuf  such that the thrid wheel pin will hit the lever and stop the chime.

The chime fourth wheel also has a pin.  This is the warning pin.

When reassembling a westminster i usually set both chime and strike warning pins 90 degrees away from their warning levers.

The beauty of most chime side trains is one doesnt have to worry too much about synching the chime train during reassembly becuse you can adjust it when attaching the chime count wheel.

It will come to you in an epiphany.  Just keep analyzing it by slowly turning the hands to activate the chime.  Watching how the pins interact with the stop levers. Keep a light touch on the fly so the gears move slowly and watch.

Strike side synching requires that the strike stop almost immediately after the strike hammer arbor's prong falls off the strike wheel. And the warning pin is set in a range between 90 to 180 degrees away from the warning lever.

If i get in a clock (or watch) that ive never encountered i take a bunch of cell phone pics.  With clocks i will also investigate the way the gears interact with levers etc before i disassemble.  And also its best to try to reassemble quickly as possible such tbat you dont forget the various quirks.

Cheers

[Beagle2]

Hello,

thank you once again.

I have removed the 'hour hand cam' to show '4 lobed cam' as pictured. And also isolated the strike side as pictured.

(I've marked the highest lobe with marker pen for my reference)

Putting back the minute hand and cycling through each quarter fairly quickly causes the clock to chime as expected...

However, if left to run normally it'll put in some extra chimes as the lever touching the '4 lobed cam' starts to rise. Normally this is at approx 10min into the quarter.

Orologi67, you mention the pin on the 3rd wheel and a lever... this may be where I am going wrong.....

I thought this pin and lever was purely to turn the chime (+strike) on and off. I've left the screw used to adjust the lever undone so it the lever flops down (circled below). At no point does this pin now come into contact with the lever.  I did this as I thought it was interfering with the chime.

Mistake?

For info, the clock arrived to me in bits, I've cleaned it and attempted to put it back together. (at least the time works ok )

 

 

 

[Beagle2]

[oldhippy]

You need to adjust the height of that lever. As I said in my first post, your description sounded like it was as I called it tripping. Watch for the warning action, take the minute hand around nice and slow, you will see it is escaping on the warning so just adjust that lever a little so it doesn’t escape.  

[Beagle2]

Great, sounds right, will try later

[watchweasol]

Hi Beagle  you have done well getting it all back together,  under Old Hippys   guidence you will do ok.  so i will not interfear,    I have attached some pictures of clock fronts and a document to give you a hand . keep plodding along  good luck.

Mike's Clock Clinic's Everything You Always Wanted to Know About Clock Mainsprings Page.html

[oldhippy]

watchweasol, 

That is very good info for someone who isn't used to these types of movements.  Don't think you are  interfering on my part,  I expect Beagle2 is only to pleased to receive all this info.  

[Beagle2]

Thank you for these responses and information - very helpful. 
 

I’m away form the clock for a few days but will report back my further attempts when I return. I hope it is still ticking when I’m back ..

[Beagle2]

Hello,

Back from my time away and have had chance to have a look at the clock again.

You're correct, the lever height was't set correctly for the (probs wrong term) warning wheel 'holding pin'.

I've experimented with different heights of lever setting (i.e. how 'high' it stick up above the pin).

When turning minute hand manually it chimes perfectly now.

However when leaving the clock to run, it occasionlly misses a chime. Even with the closest tolerance the lever 'face plate' sticks to the warning wheel pin. Looking closely at the lever contact surface shows that it's a bit scratched and worn.

I intend to take the mechanism apart again and polish up the surface. Hopefully this will help it drop. I'll polish where the long lever touches the front plate too.

I take it I should not oil where the warning wheel pin touches the lever?

 

[watchweasol]

Hi If the surface is rough there is always a probability of it hanging up the warning pin so a smooth surface is best, I lightly grease the surface to help it along.  The warning wheel when set into warning should rotate approx half a revolution before it is stopped by the lever.

http://www.clockworks.com/      This site has some interesting information regarding clocks and their repair.         cheers 

[oldhippy]

This tells me a tiny adjustment is still needed. A drop of oil on the pin is OK. Polishing the pin will make no difference, there is to much power in the spring to effect it. 

[Beagle2]

Oh dear, bit of a disaster...

I tried different new lever positions but without success. I thought I take it apart and polish and polish the lever tip as it was very rough. 
 

I needed to adjust something after reassembly. Forgetting I’d put several winds on the time spring, it wizzed free damaging one of the train wheels. 
 

I assume I need to get a new one machined from a specialist? It’s 72 teeth

[oldhippy]

Oh dear. You will need to get a new wheel cut. Just remember when working on a movement always let all the power off, no mater if its a timepiece/strike or chime. Sorry to say you have learned the hard way, have you checked for any other damage?  

[Beagle2]

Ah yes indeed. 100% my fault which in some ways makes it easier. Minor damage to another wheel but I think I can bend back the 2-3 damaged teeth. 
 

Can anyone recommend a restorer who can do this kind of work?

 

[oldhippy]

I retired from horology years ago so I'm out of touch. Just looked on google and there are many. I would drop clockboy a message as I know he still repairs clocks, I would say he is in a better position to help you then I. You can tell him I recommended him to you if you like. Let me know how you get on.    

[watchweasol]

Hi    That's un fortunate,  They can be re formed using a screwdriver in the slot,  and gently easing them up right    Be very careful as it depends on the hardness of the brass. I believe you will find mention of the tecnique in Pennman's book.  Always remove the power before doing anything, I have learnt by Bitter experience. Usually when breaking off in the middle of a job and then going back to it now I always check.

If you are lucky enough to get them all upright reshape gently with a file don't alter the profile of the teeth though.

[oldhippy]

Some are to far gone to be re-formed, these here by the time you have re shaped them the depth will be to shallow and the wheel will skip those teeth. 

[nickelsilver]

I agree with OH, and by the time these are straightened the brass will be significantly weakened if they don't break on the way.

[Beagle2]

Hello, I have found a wheel cutter online as suggested by Oldhippy. Have sent off the defective wheel today.

Not the cheapest mistake I've made in clocks.

[oldhippy]

Good for you. Repairs like wheel cutting are very expensive. If you are happy with the out come you may wish to give details as many might need wheel cutting services.