Elgin Roller Table Position

amilevad

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Jun 4, 2020
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While cleaning a new aquisition, an Elgin model 84 16S doctor’s watch, the roller table slipped off the staff and the impulse jewel slipped out of the table. I noticed remnants of adhesive (?) flaking off of the shoulder on the staff, I suspect from an earlier attempted repair. I’m ready to shellac the jewel in and “grit-set” the table, but I need to know what the correct angular position of the table/jewel is relative to the balance wheel. The drawing in the serial lookup on NAWCC suggests that it is NOT 90 degrees to the axis of the balance crossbars, as in many designs, but maybe 5 degrees or so clockwise (as seen below). Any suggestions, please?
1618515237283.jpeg
 

Skutt50

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Mar 14, 2008
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I would put the balance in the movement and mark the balance wheel with the position of the pallet fork (arbor). Then removing the balance I would install the roller table with the jewel pointing towards the mark in the balance wheel.

Fine tuning can be made later by adjusting the hairspring collet.
 

amilevad

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Jun 4, 2020
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Thank you, Skutt50! As with much good advice, it’s obvious after someone smart suggests it!
 

amilevad

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Jun 4, 2020
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The watch is running! Pretty clearly the balance arbor is a replacement- the root of the roller table flange is generously filletted, preventing the roller table from fully seating. I don’t think the original was like that. However, I got it to fit tightly enough that it is stable for now, and running again.
 

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