A Cauny With A Landeron 248 To Service

[GuiBer]

After some months a little away from watches, (but always reading new posts in the forum), I'm back to "work". 

 

A friend of mine bought a nice Cauny cronograph with a Landeron 248 and asked me to see its condition and to service it.

 

 

The watch and chronograph functions are working properly, but when I opened it I noticed some points of rust in some screws ann parts. Not very much but always disturbing to see:

 

 

 

 

I have already disassembled all the movement, (I'll show the photos in my next post), but I would like to put the main question for me in this moment:

 

- Which is the best way to get rid of the rust in the affected parts?

 

Thanks for your answers and help.

 

 

[oldhippy]

I would see what you can get rid of first using a glass fiber brush. If you have a lathe you can easily clean up the screws.  Steel parts should come up using a fine emery stick or cloth.

[jdm]

Some people suggest a tea bath, or a specialized cleaner if you're willing to spend for it.

[bobm12]

Black tea is a good rust inhibitor but will turn the spots black/dark. Then you will need oldhippy suggestion to restore them to its bright past self...some people also use toothpaste where possible. Bottom line, in the end use a fine abrasive.

[GuiBer]

Thanks for your advice.  I think I'll go for a combined "chemical" and mechanical approach.

[GuiBer]

Here are the photos I took during the disassembling procedure:

 

First going out ( after releasing mainspting load) was the balance wheel d pallet fork:

 

 

the fly-back lever spring:

 

 

the fly-back lever:

 

(attention, it's a left-hand screw)

 

 

operating lever:

 

 

winding stem and pushers:

 

 

after this, the movement can be removed (from the glass side) from the case:

 

 

after the hands removed:

 

 

now beginning the disassembling of the chronograph parts beginning with the coupling clutch:

 

 

 

and driving wheel:

 

 

then the hammer cam jumper and hammer:

 

(the hammer cam jumper is already out in the next photo)

 

 

 

the chronograph bridge and chronograph runner:

 

 

 

the minute-recording runner:

 

 

 

the sliding gear and minute-recording jumper:

 

 

 

the coupling clutch spring, sliding gear spring and friction spring of chronograph runner:

 

 

 

... and so the chronograph parts are all disassembled.

 

(to be continued...)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

[GuiBer]

The basic watch parts are very straightforward to disassemble :

 

the train bridge and the barrel bridge :

 

 

 

after removing wheels and mainspring barrel:

 

 

Note that the two "screws/posts" marked in the next photo are used to free the dial from the movement:

 

 

the keyless and motion works:

 

 

 

 

 

and finally with the center wheel and cannon pinion out:

 

 

 

everything is ready for a good cleaning and rust removal:

 

 

(... to be continued)

 

[matabog]

Thank you!

[Peixian]

Some people suggest a tea bath, or a specialized cleaner if you're willing to spend for it.

that's what i want to say. i got rid of the rust through the tea bath.it is effective. maybe you can have a try.

[GuiBer]

(not so good) News from the Landeron 248 service...

 

After cleaning all the parts, with special attention to the parts with rust, (I didn't try for this time the black tea, as I generally drink coffee instead!), for which I used a MoS2 (Molybdenum Sulphide) generic anti-rust based product. This product doesn't remove for itself all the rust, but with a very fine emery paper I was able to finish the job.

 

So the assembling began with no problems with the basic watch movement, but when I began assembling the chronograph parts, disaster arrived: I broke the screw used to fix the sliding gear spring!! My fault!!  :pulling-hair-out:

 

I ran to my computer searching ebay... and miraculously I found a German seller with the specific screw and, even better, having also for selling the barrel bridge where the screw fastens to. I didn´t hesitate a moment and immediately bought both. I decided to buy the bridge because I'm well aware of the problem it is to remove a broken screw from a bridge!!

 

They are now in the way to my home and I'm expecting to receive them to go on with the job.

 

(hoping not to have more "screwing" problems!!...) :D

[GuiBer]

...I hope to continue this post...if I am lucky enough to overcome the problems that arrived during the assembling process, and for which I asked for help and advice here:

 

http://www.watchrepairtalk.com/topic/3869-balance-wheel-problem-in-a-landeron-248/?p=39243

 

My apologies for this unexpected pause...!!

[bobm12]

Much interesting and educational thread, GuiBer! It sometimes happens that we need to wait due to situations beyond our control. No apologies are necessary. We'll be awaiting the successful completion of this movement! Your sharing is deeply appreciated!

 

Cheers,

 

Bob

[Peixian]

...I hope to continue this post...if I am lucky enough to overcome the problems that arrived during the assembling process, and for which I asked for help and advice here:

 

http://www.watchrepairtalk.com/topic/3869-balance-wheel-problem-in-a-landeron-248/?p=39243

 

My apologies for this unexpected pause...!!

you have done a good job. the process you shared is informative! looking forward to your continuous post

[Geo]

You may get a staff here:- http://www.balancestaffs.com/balancestaffs.php

[GuiBer]

11 hours ago, Geo said:

You may get a staff here:- http://www.balancestaffs.com/balancestaffs.php

Thank you Geo, but I think this time I don't need to buy from them as I found it on ebay, curiously from a Portuguese seller!

I have already received the staff, and now I am just waiting for the roller removal tool to begin the job.

[GuiBer]

Well, after some problems (balance wheel broken staff and roller) when I began reassembling the movement for which I asked help and advice here :   http://www.watchrepairtalk.com/topic/3869-balance-wheel-problem-in-a-landeron-248/?p=39243, I finally went on with the job yesterday.

The assembling of the parts is very straightforward in reversing order of disassembling. But as I was expecting the adjusting of parts to get the movement work properly was much more complicated.

The main reason for this was that, as I had to replace the barrel bridge, naturally all the cams of the sliding gear, coupling clutch and hammer (that came out from the older bridge), had to be very fine tuned patiently and with successive attempts.

Particularly tricky was tuning the depthing  between the sliding gear teeth and the dart tooth on the seconds wheel chronograph runner. If there is too much depth the minute runner will jump two minutes at a time, and with too little it will not jump!

The cam (eccentric stud) to adjust is this one :

 

The other critical adjustement is the depthing  between the sliding gear teeth and the minute recording runner wheel. the cam to adjust is this one:

If there is too much depthing between teeth, the chronograph will not run!

With these important adjustments solved the remaining assembling was easy with no problems.

Finally, I decided not to use the balance wheel I had remade because (I don't know why!), the spring was apparently interfering with the third wheel. As  meanwhile I had bought another Landeron 248 movement (as a possible backup for parts) I swept the balance wheels, so that I could finish this service more quickly. ( I'll come back later to the other balance wheel and investigate what is possibly wrong with it!).

So, the final result after assembling was like this :

 

I have been using it today for testing and it is fine, keeping good time and with chronograph functions working smoothly as well.

It was really a very "hard" job for almost a "newbie" in this hobby, but I was very happy managing to get it to an happy ending.

And it gave me the opportunity to use for the first time the "Seitz" jewel tool and a very old "Manhora" stacking tool I had bought some monthes ago.

My thanks to everybody who encouraged me and gave advice!

 

[Geo]

Very well done GuBer, they can be a bit tricky sometimes. You have learned a lot doing this service.

For others about to work on vintage chronographs, do a lot of research first and identify all the eccentric adjusters before starting, and leave them well alone during the strip down.  Unless the movement has been interfered with before, you should be able to reassemble the movement without having to re-adjust the settings.  Having said that, always check them anyway to ensure they are correct.