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Posted (edited)

I am working/learning on a 60s era Benrus wristwatch I bought on Ebay for $20.  This watch has an old-style, fixed upper balance jewel that is not accessible for lubrication via a cap jewel retainer clip like newer movements.  I can't find any mention of the proper way to lubricate it, and I am hesitant to disassemble the balance without first asking for advice.  Any thoughts on this would be greatly appreciated.  Thanks!

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Edited by Loren
Posted

These pre-incabloc jewels can be a real pain to lubricate. Sometimes if you are lucky, the screws holding the jewel in is on top. Most of the time, the screws are under the balance cock.

You have to disassemble the balance, remove the hairspring by unpinning it or loosening the hairspring stud. Then you'll see the screws underneath. 

When you remove the screws, the upper jewel plate comes off together with the regulator arm. Cleaning and lubricating the jewels can then be carried out.

Putting it back together with the drop of oil in place can be a real pain.

Hope this helps. Good luck.

Posted

Yes, I'm not convinced that cap jewel looks fixed. It looks sprung to me - early antishock possibly.

  • Thanks 1
Posted

Looks like the springy-thing screwed on top of the cock holds the jewel in place. Get the balance off the cock (loosen stud screw and open the regulator), disassemble and clean the jewels. For this style of jewel, however it's held together, I oil after assembly. From the underside, put a small amount of oil in the oil sink of the hole jewel, then insert a pin to get it to suck through and contact the cap jewel. Check the oil ring looking at the cap jewel, and add more as necessary. It's usually not necessary to use the pin again to add extra oil. It's much easier than trying to oil the cap jewel then assemble.

Posted

The springy thing is your shock spring, it keeps the end stone down on top of upper jewel and absorbs shocks , , ,    the end stone is removable like incab or Kif systems. 

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