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Posted

Greetings all. I just got through cleaning an ETA 1256 movement. It was non-running when I got it. There seems to be an issue with the balance. It's exhibiting behavior that a watch would exhibit if the upper and lower jewels had been switched. Looking at the Incabloc catalog of ETA I see that it shows that the top and bottom hole jewels are generally, if not always the same. It is the cap jewels that are often different numbers. It's tough for me to ascertain because the catalog is in French and the translations don't seem to be perfect. As I move from right to left, it appears that the first two on the right are the Inca springs, the two to the left of that are the end-stones/cap-jewels, and the one to the left of that (5th from left) would be the hole jewels. Does that make sense? Any help is appreciated. Cheers.

It also appears that I can use the caliber 1080 for the 1256 parts, with some exceptions.

 

1252_Incabloc By Factory - Eta.pdf

Posted

usually the difference between the top and the bottom is the top is usually bigger in diameter because visually looks nicer then it's usually thicker because of all the regulation parts etc. Then nobody visually cares about the other sides of the jewels are usually always smaller. But not necessarily always.

the first link because I always like to have a picture of what were looking at but? Then the second link has a image of the various Incabloc components so you can see what you're looking at. the third link to cross reference parts. Then a PDF for the parts list technical sheet etc.

then reference material is not always helpful as we have a problem? I'm looking at bestfit online currently its showing at least five different balance staffs. The third link has parts cross reference is showing nine different balance staffs. but there only showing five different balance completes.

So with all of variation is if somebody ordered a balance complete and didn't specify which one they needed that would definitely be an issue. A lot of the staff variations don't look like they would affect you but the biggest variation is whether you have a Incabloc versus the old non-shock protected.

http://www.ranfft.de/cgi-bin/bidfun-db.cgi?10&ranfft&0&2uswk&ETA_1256

http://www.incabloc.ch/images/cat/tableau-synoptique.gif

http://cgi.julesborel.com/cgi-bin/matcgi2?ref=ETA_1256

3394_ETA 1256.pdf

Posted

Thanks, JohnR725. So it does look like the hole jewels would be the same and it's the cap that is different in height/thickness. I'll see if I can see the difference between the two under high magnification. If the one that was in the top is thinner that may be where the problem lies. Thanks for the links. I didn't have the Inca one. That's a big help. Cheers.

 

Posted (edited)

I did end up seeing the difference between the top and bottom cap-jewels on the Incabloc. That was nice to learn. Thanks, JohnR725!

Still, even after making sure the end-stones were in their proper places, the watch was making an odd audible tick intermittently. And it would stop. I took a second to look at the balance assembly and saw that the regulator arm was displaced a bit off of the top of the balance cock. I hadn't removed it for cleaning, so it wasn't me. No matter though. I situated it properly on balance cock and the watch is now running very strongly. I'll see how long it does so. It is no longer making the odd audible tick so I'm pretty confident that all will be well. Thanks all !

Premature victory dance. I should have known better. Little bugger stopped again. Rats!

 

 

Edited by MrRoundel
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