Jump to content

St96 Restoration Walkthrough

Recommended Posts

ST96 Restoration Walkthrough


I got a new project to start on: restoration of my brother's watch he got for his 9th birthday.




This is not an expensive watch in dollar terms; but the memories and history are priceless, and one I really want to restore to excellent condition.

It stopped running decades ago, but he has still kept this watch for nearly 40 years, how many of us can say the same about their first watch?!

My brother has placed a lot of trusted in me to restore this watch, and I want to repay that trust by restoring this watch to the best of my ability.

Note his name (blocked out) and date it was given to him are engraved on the back plate. 




After opening the back I was pleasantly surprised to see it was a 17 Jewel movement ... so for it's day it was a proper watch; and not a cheap throw-away item you buy at a service station.  This would have been purchased at a professional jewelers back in 1975.


Unfortunately, the first issue was discovered.  The locating ring is missing, and the only thing holding the movement in place is the stem ... not good.




So the disassembly begins. 

Once removed from the case, the hands and dial were removed to get to the movement.


Then the first of the motion work is to be removed.

Remove the Hour Wheel




Then the Minute Wheel pinion and it's Guard Plate.




Next remove the intermediate pinion for the Minute Wheel.  Also notice the over oiling of this movement, someone got very enthusiastic with their oiler!




Again oil everywhere!  Here's is the Minute Wheel glued to the Guard Plate with oil.




Pull the Cannon Pinion and remove the Endstone.




Release the spring tension from the Mainspring.




Remove the Ratchet Wheel and Crown Wheel

Look at the flood of oil over the bridge!




Second issue with this movement.  The thread for the Crown Wheel Screw is stripped.  It looks like someone has been inside this watch, many years ago, to try and see why it stopped running, and unscrewed this anti-clockwise; not knowing that it's a reverse threaded screw, and stripped the thread :(




Continuing with the dismantling ... remove the Click and Click Spring.

Note the orientation of the spring.




Remove the Barrel Bridge




Remove the Balance, Pallet Fork Cock, and the Fork.




Remove the Centre Wheel and Third Wheel.




Remove the Escape Wheel and the Mainspring Barrel.




Remove the Endstone from the Centre Wheel Bridge, and then remove the bridge itself.




Remove the Centre Wheel




Whatever lubricates were used on this movement it has crystalized into a nasty mess. 

I tried to capture it on this photo, but it didn't really comes out as I'd hoped .... but notice all the white specs.




To finish off, remove the Keyless Work.

Start with removing the Setting Lever Spring.




Next unscrew the Setting Lever, remove tension from the Yoke Spring, and then remove the Yoke.

Note: more evidence of over oiling it present here.




Note the orientation of the Yoke Spring.




Lastly, remove the Endstone from the Main Plate, and you are complete.




After fully dismantling the movement, I opened up the Mainspring Barrel and found what the original issue must have been ... a broken Mainspring.  This is the third issue that needs to be addressed to restore this movement.

Probably broken by a young boy over winding his watch :)

Note: The break in the spring, and how it doesn't attach to the Barrel Arbor any more.




So with a missing Locating Ring, stripped Crown Wheel thread in the Barrel Bridge, and a broken Mainspring: I need some spares!!

.... off to the Fleabay ....


Being a movement in an obscure brand of boys watch, I wasn't exactly hopefully in finding spares readily available ... but praise the Lord Jesus Christ, they were there in abundance!

It seems India has cornered the market on ST96 Movements :P  They had it least 10 to choose from.

I ended up choosing a "Rare" Tressa model in "Excellent" condition, that was a "MUST SEE"


I placed an offer for AU$28 on this rare collectable (including shipping) and won it **chuckle**




Regardless of the hype, it is guaranteed to work for 12months, and is the movement I require to secure the parts I need.  Including that all important Locating Ring.




With free shipping comes a long wait for delivery to Australia ... 12-22 days.  So while I'm waiting for the watch parts to arrive, I'll clean up the case and bracelet.


... to be continued

  • Like 1
Link to comment
Share on other sites

Boy you are one busy guy!

I just realised that it is winter down your end of the world, does that have anyth thing do do with your high output just now? Being summer in Scotland, the watch repair work gets put on the back burner. I'll get going again properly in the winter.

Link to comment
Share on other sites

Hey Geo,


Yeah it's winter here; but that isn't why I'm dedicating so much time to servicing watches.  I'm retaining myself for a new career is a watchmaker: hoping and praying to the Lord that I gain employment as an apprentice.  I know that this career is very tough to get into, and you need an edge over the other applicants, and to demonstrate to your prospective employer that you have the God given gifts and ability to do the work.


I am also doing it so that I'm sure it's something I enjoy and want to do for the rest of my working life ... and indeed it is!!


I'm posting these walkthroughs up firstly to give others confidents that they too can service watches; as Mark gave me that confidents through his videos.  And also by writing these out, and using the correct names for all the components I'm teaching myself at the same time :)  So if I get anything wrong, in procedure or terminology, please correct me so I may learn from my mistakes.

  • Like 2
Link to comment
Share on other sites

Me too, I wish you a great future and success in your new career. Excellent post!



PS. Check out Timezone watchschool/otto frei site for ST 96 information (not necessarily ordering but pdf and pics -- I mean extra info)

Edited by bobm12
Link to comment
Share on other sites

A few points..


1.  movement spacers are meant to fit various size movements to various size cases.

In this case you may have sourced a spacer that will fit your ST96 but it may not be the same size as your case.. not only the diameter but the depth (depending on case thickness) may vary.


Funnily, I notice that automatics usually have the same inner diameter/outer diameter for the same movements but for manuals it varies greatly..sometimes only around 1mm but frustrating nonetheless.


2.  Both movements have different shock protection, your brother's watch has incabloc (which I think is superior), the india watch has what looks like trishock. Inca is more desirable but which ever you use, both ends must be the same and the balance has to match. This is important if you plan to swap parts around.


the below are my personal views so don't take it too seriously....


3. The finish on the India movement is the hammered finish... personally I detest this.


4.How do you plan to work around the stripped thread? Are you planning on swapping the movement complete?, that would be a shame as that's a major portion of the originality of the watch. Not impossible and only worth it if originality is important.



Link to comment
Share on other sites

Hi Lawson, as Anil said, I was also wondering about the strip thread. How are you planning to fix it? Are you going to re thread it and find larger diameter screw or something of the sort?


Please, keep us posted. This thread is getting very interesting (no pun intended).

Edited by bobm12
Link to comment
Share on other sites

I was going to do a complete swap over of the movement, I probably should have explained that better in the thread. 

I don't have a helicoil set to repair the stripped thread, and I'm not even sure if they even make a left-handed helicoil that small.

To my brother, the watch is the case, dial, hands, and bracelet ... whether it has the original movement will not mean anything to him ... This is a "watch" restoration; not exactly a movement restoration.


I actually thought the movement in the Indian watch was a better grade of ST96, giving my brother a more reliable watch.  I understand that the Incabloc System is very easy to work on; but I didn't have too much trouble with the Trishock System in the 7S26A, and the jewel is being stabilized at three points with Trishock, instead of two with the Incabloc ... isn't that superior?  Please correct me if I'm wrong, but also give reasons why my train of thought is wrong, as I'm really trying to learn as much as I can, and I greatly appreciate your wisdom and feedback.

Edited by Lawson
Link to comment
Share on other sites

Sorry Lawson, no wisdom here whatsoever! :) I feel a little like the blind leading the blind if you will, in this case... But, although I have never done it or seen it done, I suppose there has to be a way to correct a stripped left thread. Also, it seems that because it is in the main plate (mmm, because it is in the main plate, isn't it?) the work may has the advantage to be done right in the movement holder if you can get the proper tool to do it...Just a thought...Maybe a more experienced member can shed light on this matter...

Link to comment
Share on other sites

Hey Bob, thanks for the kind words mate.  The stripped thread is in the Barrel Bridge.  And I'm sure there are a few ways to re-thread it, even some of the two-part epoxies are stronger than steel these days, and might be an option.

I won't be throwing the original movement away by any means ... But I think I'll wait until I'm an apprentice in a full workshop, and discuss it with my mentor.  Might be a future apprentice job for me to learn on :)


I also have my Dad's Tudor Oyster Royal with 18ct Gold Bezel, that he brought in the 50s when conscripted in the national service overseas ... it's a real mess, and that will be a FULL Restoration, regardless of cost ... but a long way off in my future.

Link to comment
Share on other sites

Incredible documentation on this restoration project and incredible back story on your career direction change.  You are at this level after only a month?  I don't think you should have any problem with the career redirection given your skills and dedication!  I am truly impressed.  I too wish you all the best Lawson.

Link to comment
Share on other sites

Tri-shock is not a generic term for any three-legged shock protection.. its actually a trade name. Similarly the shock in the Seiko is called a 'diashock'...


I believe the difference is in the quality of the metal used for the spring.


As to thread repair... I would think that a proper repair would be made by using a bit of brass rod pressed into the hole (once the old threads are drilled out) and then drilling and re-threading back to original.

This is opposed to an improper repair involving loctite or other types of epoxy..!!!  :D (I have to admit, I've been guilty of this!)..



Link to comment
Share on other sites

Trying to contribute and learn, I found very little documentation on the ST 96 also called FHF 96. I also looked under FHF 969 which is similar. I'm posting the compiled relevant info in pdf format for completeness. I wish I had found the real data but I guess this will have to do.




Lawson, I hope you get the parts soon so we can see the end result! Great job, keep at it!



Link to comment
Share on other sites

Your are welcome, Lawson! I'm hoping some other member has the actual service data for this movement and can post it here for completeness.


By the way, since there is no exhibition back on your brother's watch, you have an alternative -- if the ring in the fleebay watch doesn't fit -- to use plastic movement holders (no one will see them) if you think it appropriate...

Link to comment
Share on other sites

Great post Lawson,

I must admit repairing the thread especially a left hand thread would be a problem for most and me. Getting the correct tap would also be a big issue.

I know where you are coming from as I restored my first watch that I was given on my 11th birthday  i.e it's now 50 years old. Like yours not of great value ( an EB8800 movement ) but it has great sentimental value to me.  It was very badly rusted and I had to change most of the movement parts and really I should have changed the entire movement but very satisfied with the end result.

Edited by clockboy
  • Like 1
Link to comment
Share on other sites

  • 2 weeks later...

The replacement movement has arrived from India!!  Errr ... but I missed the postman :rolleyes:

So I have to take the postage receipt in and pick the package up from the post office this afternoon, once the postman has finished his runs and returns to them.


I'm sure it will need a full service, and I hope their Indian "Full Service" hasn't wrecked anything ... we will see, and as per usual I'll posts heaps of pics.


Lamb roast with my parents tonight (Mum's Lamb > Watch Restoring!!), so I don't know if I'll start working on it late tonight, but I wanted to update this thread and keep you fellas posted.



Stay Tuned ....

Edited by Lawson
  • Like 1
Link to comment
Share on other sites

The Indian Connection

So I finally got around to picking up the watch I purchased from India.
It was very well packaged in its own little unbleached cardboard box, and once opened I was presented with what looked like a brand new watch. The case is beautifully polished, no scratches on the glass, brand new leather strap, and even the winding crown looked new  ... I was impressed.




So I put it on the AceTimer Timegrapher to see how the movement was running.
LOL ... It looked like a B52 drop in Nam!  Just as advertised, "Keeping Good Time", and "Fully Serviced" :jig: 
You can't hide from the Timegrapher!



I opened the back and donned my loupe to unscrew the Setting Lever and noticed that my counterpart in India mustn't have had a 0.8mm Driver ... and this is what happens when you use a driver too large for the head of the screw. (Took the picture with the movement removed for a better image)




Next I removed the movement from the case and removed the hands.  The dial looked in perfect condition.




Once removed though you could see it had been made from a scrap piece of tin, complete with grinding slag  ... I must say that I am still very impressed with the face of the dial, created from this piece of offcut.




Further inspection under the loupe, I noticed the "Full Service" included oiling the jewels with all purpose grease ... ROFL!  I tried to get a good picture off it, to increase the comical value; but this is the best I could do.  I checked the endplay on the pivots and as expected, there was a considerable amount of play. 




Even the post that holds the yoke has been mushroomed out like a rivet, and I was unable to remove it *Chuckle*



All in all, this movement has paid it's due, and is completely worn out.  Everywhere you look the wear is extensive.

So I don't think I'll be using this one for my brothers keepsake, but still, it's all there, it ticks, and good to practice on without the worries of damaging an expensive movement.





Link to comment
Share on other sites

Good eye opener, Lawson and sorry it didn't meet expectations. Can you use anything at all?


Hey Bob,

I'm soaking the parts in lighter fluid at the moment, to get the worst of the grease and grime off before I put them in the cleaning machine.  I'll inspect the parts after they come out of the cleaner and go from there.

I'm not one to easily give up on a project.

Link to comment
Share on other sites

Excellent state of mind for this project, I'm with you on that, never give up!


By the way, What are you going to do with the stripped bridge? It appears this in not the movement fit for a swap, is it?

Edited by bobm12
Link to comment
Share on other sites

  • Create New...