Hi,
I have a question concerning a pivot replacement which seems to have been done some time ago. How does one go about getting old pivots out of the balance staff. Tools? & Technique? Any help greatly appreciated, Thanks, John

For those of you who may have read this and wondered what was going on. The balance staff is from a British watch movement. The staff has had both pivots cut off and replaced as evidenced by a seam in the continuity of the staff at both ends ie. near the oil trap. British watchmakers dealing with this vintage of watch/balance staff often do replace the pivots only as oppossed to replacing or making a new staff. I might also add that this staff is made of two parts one being the staff arbor and the other is brass for rhe the balance wheel seat and the collet of the hairspring, thus making it a complicated rebuild.My curiosity led me to ask how to get the replaced pivots out so that I might copy their technique. I have been advised that heat and pull is the answer and if this doesn't work a whole new staff is in order. Sorry for any confusion I may have caused within the readership. John

I have no idea how it's done but I'd love to see a close-up photo of the repair. I do know that American watchmakers were encouraged to make their own staffs but it's far beyond what I can do.

John,

Henry B. Fried has a whole chapter on repivoting in Bench Practices for Watch and Clockmakers. In general, the methods are the same as in repivoting any wheel arbor. The difference being that the balance staff pivot stump should not be faced off any lower than the diameter intended for the thickness of the drill hole. Otherwise the diameter of the replaced pivot will not match the curvature of the conical part of the pivot.

It takes some good pivot drills, a lathe that is dead-on, and a lot of practice. You are better off learning to turn staffs first.