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St96 Restoration Walkthrough

Lawson
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Lawson Super WRT Addict

Lawson

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Geo, on 26 Aug 2014 - 5:44 PM, said:

Best advert I have seen for not buying from India!

 

ROFL!  Come on Geo, that movement is well on the way to getting a Geneva Seal it's not funny ...

Not only are all the train gear wheels chamfered and polished, every single edge of the watch has a chamfer  :rolleyes:  That's a good start isn't it?

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64americandeluxe WRT Addict

64americandeluxe

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Hi Lawson,

I totally understand what you are going through.  I too, am new to watch repair.  Last spring I bought a non-working, mid-1960's Elgin with the same, ST96 movement.  Turns out it had a broken stem and missing crown.  This was my first total tear down and reassembly.  I was able to get a donor movement as you did and got the watch running.  I really enjoyed working on it and learning a lot along the way.  The thing I struggled with the most was installing the train bridge.  The escape wheel leans over quite a bit prior to the bridge going on.  Trying to get all three pivots aligned is delicate and took me a while to get it installed.  There must be a master watchmaker's trick to this or maybe it's simply practice.

 

On another note, I also have a 1956 Bulova with an 11ACC movement that also has a bridge with a stripped crown wheel screw hole.  I am tracking down a parts movement for this one also.

 

Keep up the good work!

Roger

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Lawson Super WRT Addict

Lawson

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Thanks for the response Roger.

 

There is a trick to installing any train bridge mate, and the words Mark uses are very accurate ... "you worry them in place".  What he means by that is as follows:

 

Firstly take your time with placing the bridge down on the gear train, as taking time to accurately place it, will save heaps of time with aligning the pivots.  If your not happy with your initial placement, it's better to remove the bridge and try again; then have the pivot points way out of place, and be sliding the bridge around over the gear train.  And the more you do this the better you'll get at it.

 

With a piece of pegwood, press down lightly on the top of the bridge ... firm by light (and this pressure is where practice and experience comes into play).  Then with a fine pair of brass tweezers (I use Dumont No.4s) lightly move the gear train back and forth, switching between gears if possible (say a 1/32nd of a turn, but DO NOT FORCE THE MOVEMENT) ... this back and forth "jiggling" of the gears helps them into their place, and is what I believe Mark means by "worrying" them into place.  You'll feel through your pegwood when the pivots drop into place.  This is the method I use, and I've now worked on MANY bridges, both mechanical and analogue quartz (including the 5J22A with 9 pivots on a plastic bridge to align!!), and this method works well for me, and I've never damaged a pivot yet.

 

Keep up the good work Roger, and I wish you many hours of enjoyment working with watches :)

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anilv Distinguished Member

anilv

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To add to watch Lawson said..

 

You need to be able to view the watch from the side... its usually the escape wheel that's the last to fall into place. Viewing it fom the side, you cas see which way its 'tilted'. Knowing that the bottom pivot is in the plate, you now have to manouver the top of the escape wheel. If its tilted to the left then you can either lightly touch the right side at its highest point to bring the top pivot into position. If its tilted away from you then you can touch/press on the edge of the escape wheel closest to you to bring the wheel upright.

 

Once you get them in place, dont remove your pegwood until you get the screws in.. when screwing in, constantly check that the pivots have not come out of their holes ...

 

Patience is the key.

 

Anil

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Lawson Super WRT Addict

Lawson

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Hey Gang

 

It's been a long road finding parts for this watch, and after the "Indian Connection", I was very wary in purchasing parts via Fleabay.

Those who have followed my posts will know I'm currently servicing an AS1012 movement in a little "Cocktail Watch".  Well, the same lady gave me another

watch as a "practice" watch that I could keep, and guess what ... it had an ST96 movement!!  Yeah baby!! :woohoo-jumping-smiley-emoticon:

 

So I pulled a parts tray with my brother's watch in it and got to work!!

 

post-246-0-50713400-1418289248_thumb.jpg

 

It even had the same brushed finish to the bridge plates, so it all matches perfectly.

Here she is all complete and shinny!!

 

post-246-0-34896000-1418289254_thumb.jpg

 

Needless to say, by brother was thrilled to bits seeing the first watch he ever owned ticking away once again :)

 

post-246-0-96837700-1418289257_thumb.jpg

 

A good end to a fun project, hope you all enjoyed it too.

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bobm12 Distinguished Member

bobm12

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This is an amazing thread: Watch servicing in detail about a typical movement for learning the subject, and finally a happy conclusion, almost a miracle considering the estate of the original movement! Very nice, Lawson! One of your best ever!

 

Cheers,

 

Bob

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szbalogh Super WRT Addict

szbalogh

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Disassembled the same movement taken from a "Sandoz" from India. 

Great info here! thank You!

Noticed that i had no yoke spring. It was working but the stem jumped back from the setting position to the winding position.

On the other hand the watch was stopping always when thr second hand reached the 45 position. 

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