Balance Wheel Problem In A Landeron 248

[GuiBer]

I began servicing a friend's Cauny with a Landeron 248 movement,

 

 

whose story I am telling here:

 

http://www.watchrepairtalk.com/topic/3784-a-cauny-with-a-landeron-248-to-service/

 

But now, after cleaning, oiling and assembling all the parts, I am not getting the movement to work consistently:

 

When I install the balance wheel the movement starts working, but when I fasten the balance cock screw, even slightly, the balance wheel stops. I tried it several times but always with the same result.

 

During the movement assembly I verified carefully the run of all the gears, and apparently theres is no abnormal resistance in the movement as when I, (prior to install the balance wheel), move the pallet fork from side to side I can see the escape wheel moving accordingly.

 

Any suggetion of what might be the problem?

 

Thanks

[Andyclient]

I would think it lies with the balance pivots or the pivot jewels from what your saying are the jewels totally clean have you tried running it with out the end stone in place , can you remove the end stone from the front plate? i realise you can't from the balance bridge

[syfre]

You have a end-shake problem, how do you have clean the balance jewel ?

Do you have disassemble the cap jewels ?

May be you tighten the setting screws a little too much.

 

look here :

 

http://www.watchrepairtalk.com/topic/1006-end-shake-on-new-balance-staff/

 

Mark explains some methods to adjust the end shake (like the pig's ear method ... lol)

 

(but If your watch was running before disassembling you must not need this kind of tricks)

[mousekar]

I agree that this is an end shake problem. Another thing you may want to check is to make sure the balance cock is not bent. This same thing happened to me early on when I started to clean watches, and I had mistakenly put pressure on the balance cock and had bent it slightly (I won't discuss how I did this), so when you screw it down, the end shake was effected.

How i figured this out was to look at the alignment of the balance cock screwed down without the balance being attached. Then it was obvious.

Note: I was working on a vintage Swiss trench watch, so that may be easier to bend and easier to see. I just offer this as something else to check, if it doesn't seem like the pivots or end caps are the problem. I'm not a professional, only a hobbyist.

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[clockboy]

It could be simply the jewels are upside down or some movements the upper & lower jewels are different. If this is not the case then a close inspection of the jewels for cracks etc & a close inspection if the staff. If this is all OK then it could be a slightly bent staff which should show as it runs. Or was there any packing under the bridge when it as disassembled.Sometimes if a new staff is fitted but it is a little tight a work around (bodge) is a thin packing is put under the bridge.

[GuiBer]

Thank you all for your advice...

 

Andyclient and syfre:

 

I didn't disassemble the cap jewels. The base plate was cleaned with the jewels in place. I just oiled a little bit the end stone in the plate. I have inspected it and apparently is ok.

 

mousekar and clockboy:

 

The balance cock seems ok to me. I didn't put any pressure on it when disassembling or assembling.

I also didn't notice any packing under the bridge when disassembling.

 

...

 

Perhaps I'll go for a trying with the packing "trick", although I would like a more technical solution, as eveything was running ok before disassembling!

[clockboy]

The packing trick is only for a tight staff if it was ok before the service then look for the actual fault

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[StuartBaker104]

Are you sure that the balance cock is going down square? Sometimes a balance cock will tilt over towards the balance as it is screwed down, and you have to push the outer edge of the cock down to keep it square then tighten the screw a bit more and repeat.

S

[Geo]

If there was any hard dried old oil left in the jewels after cleaning, it may have expanded when you applied fresh oil. One of the first movements I worked suffered from this. A thorough clean as described below fixed the problem.

Soak the main plate complete with balance attached in a jar of lighter fuel for twenty four hours to soften the dried oil. Now place the jar in an ultrasonic cleaner and give it a blast. Since doing this I have never experienced any problems.

[GuiBer]

Geo, thanks for your advice.

 

If meanwhile I don't discover other cause for the problem I will surely get courage to disassemble all the movement again and try your suggestion!

[GeorgeClarkson]

I am with Geo on this: had the same issue on a Landeron 248 movement I got for spares and then decided to fix. Old oil was blocking the balance wheel to turn properly, so I soaked for a couple of hours in the liquid I use to clean parts ( alcohol or spirit as some may call it) and then disassembled the jewels, to find out black stains of oil. A sharpened toothpick was used to remove all the solid material and an ultrasonic bath did the rest of the cleaning.

[jnash]

also make sure that the balance is not rubbing on the screw or the product that holds the pallet

[GuiBer]

After deciding to go for a  deep new cleaning, as suggested by Geo and George, the result was not unfortunately according expectations!

The problem remained!!

 

I decided to replace the incriminated plate jewel, which I did... with no success! The balance wheel just didn´t want to run smoothly as it should!

 

But things would get even worse!!

 

I was forced to admit that the problem could be on the balance wheel itself, so when I was trying to "persuade" it to work properly, the inevitable happened :

  

- the staff inferior pivot broke!!

 

So, i had to face this like making part of my learning process!

 

And there is no doubt that I will learn a lot with this movement, as my next task will be to replace the balance staff for a new one ( that I have already ordered).

 

As it is the first time I will do it, I have prepared two scrap balance wheels to try the procedures!! ( I have also ordered a roller removal tool for the job).

 

Wish me luck, please!

[bobm12]

Hi GuiBer,

 

Good luck wishes are always implicit in the site! :) I hope you are able to finish the walk through and solve this glitch! I haven't worked in this movement and find the whole adventure very interesting and exciting.

 

This staff replacement would also be of particular interest so, please, do this one too if it is not much to ask!

 

Cheers,

 

Bob

[Andyclient]

Marks done a video on replacing the balance staff on a 1940's Cyma that you would probably find useful , good luck with it , I have still yet to do my first one so watching this thread with anticipation and fingers crossed for you

[GuiBer]

Thanks Andyclient,

 

I have already view Mark's video (several times!). It's a pitty I don't have a Platax tool, so I'll have to manage with my modest (and very old) staking tool.

[GuiBer]

After a one month pause after my last post here, I'm back to work in the Landeron 248, and I have a new question.

But before, I'll tell what has happened meanwhile and some more mistakes I did :

 First mistake : as I needed a roller remover to separate the roller from the broken staff I ordered one from Cousins, the cheap one, - big mistake - because when it arrived I concluded it was completely useless!! One more time it´s proved that Indian cheap tools (most of the times) don´t work! I complained this to Cousins, ant they kindly accepted to sell me the Bergeon remover discounting what I had paid for the Indian one. Nice guys from Cousins!

After a week arrived the Bergeon tool and then using it, I did my...

Second mistake: I applied to much force for releasing the roller from the staff and what I got was a splitted staff and a roller with part of the staff stuck inside of it.

So I had to make a new order to Cousins for a balance roller and a new staff, because I was suspecting the one I had already bought was not the correct version comparing with the now broken old one.

After ten more days waiting for the arrival of my order, finally I received it today and I was back to work some minutes ago.

Everything went right about fitting the new staff to the balance wheel. It was my firstt try with this kind of job, I went very careful guided from Mark's videos, and I think I did it right!

Next step was fitting the new roller to the balance wheel staff, and here I have an important doubt: I was expecting that the roller could enter a little in the staff (about half way?) but it doesn't. It stays just in the top of it !!

So I decided not to force it down and come to the forum and ask if I can press it down to its place, or must I reduce the diameter of the staff or enlarging the bore of the roller?

Your help will be much appreciatted, Thanks!

 

[GuiBer]

... I measured staff diameter and roller bore and they are both 0.5 mm!

And I must also say that I don't have a lathe to work on the staff!

[clockboy]

I have only changed a few staffs (& made one which took two days to make) but fitting the rollers were tight-ish but no real force was required. If you have to reduce anything then the roller bore is the one to reduce. Perhaps a smoothing broach would be the best tool.

[GuiBer]

51 minutes ago, clockboy said:

I have only changed a few staffs (& made one which took two days to make) but fitting the rollers were tight-ish but no real force was required. If you have to reduce anything then the roller bore is the one to reduce. Perhaps a smoothing broach would be the best tool.

Thank you for your advice Clockboy!

That was the solution I was also thinking of. 

I was even thinking to use the smallest reamer of my Seitz Jewel Tool for the job. It has a final diameter is 0.69mm, but as its tip is conical, I think I can manage with some care just to create a entry diameter in the roller just a little over 0.5mmm.

What do you think of this possible solution?

[clockboy]

I think that a reamer would be to drastic also finding absolute centre could be an issue. Using a smoothing broach in my opinion would give you more control.

[GuiBer]

On 28/04/2016 at 7:04 AM, clockboy said:

I think that a reamer would be to drastic also finding absolute centre could be an issue. Using a smoothing broach in my opinion would give you more control.

I absolutely agree with you, but as I had no smoothing broaches I decided nevertheless to risk the job very carefully and by successive attempts with the smallest reamer I have.

I think I managed to sucressfully put the roller on the staff :

So, finally, it was time to go on with the assembling of the movement whose story I began here:

http://www.watchrepairtalk.com/topic/3784-a-cauny-with-a-landeron-248-to-service/

 

 

Edited May 4, 2016 by GuiBer
wrong link

[bobm12]

Excellent job!

Cheers,

Bob

[RyMoeller]

Good work!