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Removing Sicura Screw Back


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The main points with the nut & superglue method:

 

1. It works on any screwback.

2. It works even if it rusted solid.

3. It doesn't mark the back.

4. It comes apart easily.

5. Its cheap.

6. err - that's it.

 

Nuff said.

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Thanks to this forum, I found about this technique.  But initially, I was hesitant to use it.  It sounded crazy!  So I figured posting more cases of its use will give others confidence on the technique.

 

The watch in this case was from a watchmaker.  He himself wasn't able to open the back case - see all the scratches at the back.

 

post-603-0-16755500-1434170044_thumb.jpg

 

I used a superglue - remover pair from our local hardware store.

 

post-603-0-94451100-1434170030_thumb.jpg

 

It is best to center the nut as precisely as you can to facilitate easier turning.  Otherwise, the pressure exerted on the case back threads won't be even.

 

post-603-0-27071500-1434170013_thumb.jpg

 

post-603-0-77602600-1434170002_thumb.jpg

 

The glue remover turns the superglue into gel-like, allowing you to remove the nut after a few hours of applying it.

 

post-603-0-48710000-1434169993_thumb.jpg

 

post-603-0-65164500-1434169962_thumb.jpg

 

...and it leaves no mark.  Not that it matters in this case.   :D

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  • 4 years later...
On 4/20/2015 at 5:13 PM, noirrac1j said:

NICE!! Congratulations on a job well done!! John that movement looks like a BFG 158 31/7 of which I have many many spare parts of every sort (including balances). You've already mentioned it was a SIC 39? I've never heard of that particular movement in a Sicura, but who knows? It sure does look like a Baumgartner 158 31/7 with 25 jewels which means they've included some jewel caps for the pivots and probably a jeweled rotor bearing for the auto-winder. If I could see the balance I could tell for sure--Does it have a KIF shock system? It is shaped like a little triangle. In any case, If you need any parts, just send me a picture of it and you can have it for free--just pay the shipping. I have entire movements so every little screw, spring, and lever is available!

Still have parts? Struggling to source a spring or two. Thanks!

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40 minutes ago, noirrac1j said:

Hello,

Sorry I've been caught up with current events, but yes I have lots of spares. Which springs?

 

J

I may have found the spring. Do you have any tips on assembling the date/day jumper & corrector works? For the life of me, I cannot figure it out. Separately, do you have any of the Novochoc shock jewel & springs? Missing a spring, and my jewels are pretty beat up...

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8 minutes ago, MikeRaleighNC said:

 

I may have found the spring. Do you have any tips on assembling the date/day jumper & corrector works? For the life of me, I cannot figure it out. Separately, do you have any of the Novochoc shock jewel & springs? Missing a spring, and my jewels are pretty beat up...

Yes I have lots of assembly pictures, remind me which BFG 158 31/7 you have? Is it a sicura jump hour or a Cordura day /date?

Joe

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9 minutes ago, noirrac1j said:

Yes I have lots of assembly pictures, remind me which BFG 158 31/7 you have? Is it a sicura jump hour or a Cordura day /date?

Joe

It is a Cordura day/date. That would be a huge help! Also, if you do have any of the jewel/spring assemblies, that would be a godsend. :)

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Hello! Sorry for the delay. Please see the attached photos. The white arrows point to the place where the springs contact to keep the date wheel and quick change mechanisms ( the two levers near the 9' hour marker)  in place. I have jewels and springs, so just let me know which ones specifically you need.

 

Regards,

JSlide1.JPG.9d9d8cbf799a381414905e1376351ba7.JPGSlide2.JPG.a2044f100f319350939cda929a838bdf.JPG

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1 hour ago, noirrac1j said:

Hello! Sorry for the delay. Please see the attached photos. The white arrows point to the place where the springs contact to keep the date wheel and quick change mechanisms ( the two levers near the 9' hour marker)  in place. I have jewels and springs, so just let me know which ones specifically you need.

 

Regards,

JSlide1.JPG.9d9d8cbf799a381414905e1376351ba7.JPGSlide2.JPG.a2044f100f319350939cda929a838bdf.JPG

You're the man! I cannot thank you enough. Finally got it together. Part of my problem is that I was poising the springs in the top bridge/cover and trying to place over the correctors/jumpers. Finally figured out that the cutaways are for slipping the springs into place.

The jewels and springs are both of the novochoc (triangle) antishock balance jewels and springs (main plate side, balance cock side). See picture.20200409_113525.thumb.jpg.0a031c28691ab3dff501dfac86fdebe9.jpg I don't think my balance staff/pivots have any problems, but if you have a balance complete, I would happily take it and compensate you fully for that. I really appreciate your help and time on this!

 

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