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Gruen 522CD (Felsa 4019) balance pivot not going into jewel jewel


dieale2

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Hello folks, I am practising on a Gruen 522CD. I installed the train wheels and escapement to make sure the watch is running fine. I use my microscope to inspect the jewels and pivots because I can't see them with a 20X loupe. I found that the balance pivot won't go into unless I force the balance cock down with the cock screwed in. Maybe I need to bent the cock down? That seems pretty barbaric.

Below you can see the pivot barely moving into the jewel. The bottom pivot does the same thing.

guren_cal_balance_pivot.thumb.jpg.79b00e2b1396886ffb0e3d79265fb0b6.jpg

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[emoji848]


I think I need more info.

Is it that with the cock screwed down you have a gap between both pivots?? And you have to drive the pivots into the jewels to engage them? That would be a bad endshake situation and before bending cocks I’d adjust jewels.

On the other hand, I can’t make much out of the pic, but it don’t seem right to me...is the jewel opening deformed and that’s why the pivot doesn’t engage? Is it a capped jewel?

Cheers!



Sent from my iPhone using Tapatalk

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Going back to the start: did this watch run at all before you started working on it?

Check the pivots are not "mushroomed". It may be easier to fit the balance without the cap jewels in place, plus you can see more easily.

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I had a similar problem with an omega 39.5L. Balance was bent a little bit. Returned it back to normal and all  was fine. The bridge on those (omega) is very thin. Check that it's not bent. Then possibly the staff is bad/worn. Incorrect jewel seating. Remove the balance and place it on a flat true surface with reg. removed, (not sure but may have to remove the jewel anyways if it protrudes above the cock) and check for gaps. If you can see any amount of a gap at all this is incorrect. If it looks good there are other problems already addressed in previous comments.

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19 hours ago, jguitron said:

emoji848.png


I think I need more info.

Is it that with the cock screwed down you have a gap between both pivots?? And you have to drive the pivots into the jewels to engage them? That would be a bad endshake situation and before bending cocks I’d adjust jewels.

On the other hand, I can’t make much out of the pic, but it don’t seem right to me...is the jewel opening deformed and that’s why the pivot doesn’t engage? Is it a capped jewel?

Cheers!



Sent from my iPhone using Tapatalk

Here are some relevant microscope pictures. This is a pretty normal modern movement with calendar complications. The balance is shock protected. The first photo was me shooting at 200X through the upper balance jewel. Sorry for the lack of context.

Quote

Going back to the start: did this watch run at all before you started working on it?

Check the pivots are not "mushroomed". It may be easier to fit the balance without the cap jewels in place, plus you can see more easily.

The watch didn't run at all at the start. The pivots do look a bit "mushroomed"?

Quote

Remove the balance and place it on a flat true surface with reg. removed, (not sure but may have to remove the jewel anyways if it protrudes above the cock) and check for gaps. 

I put the balance cock on a jeweler's anvil and it looked straight on. I included a picture of the cock sideways. Looks straight to me.

 

 

guren_cal_balance_cock.jpg

guren_cal_lower_balance_pivot.jpg

guren_cal_upper_balance_pivot.jpg

guren_cal_bird_eye.jpg

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Wow, that lower pivot looks like it either has metal worn, displaced, or replaced, as if there's a glob of solder on the tip. It doesn't look good. I wonder if it's possible that you could polish the pivot down on a lathe or in a pivot-polishing tool? I'd be considering finding a new staff for it though. Good luck.

Edited by MrRoundel
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