2. How balance staffs are replaced Ken Pell

3. Components of balance assembly Wheel (split or solid) Staff (riveted or friction) Hairspring (flat or overcoil) Roller (single or double)

4. Balance wheel Roller Hairspring

5. Wheel Roller and Jewel Staff

6. Roller Hub Hairspring Hub Pivot Wheel Hub

7. Why they must be replaced Trauma, such as dropping or bumping watch which damages the staff and jewels

8. Broken Pivot

10. Pre staffing Clean movement Examine and replace balance jewels Identify movement early and secure new staff

11. Good Hole Jewel

12. Cracked Hole Jewel

13. Chipped hole jewel

14. Selecting replacement staff Determine grade of watch Use Elgin reference for staff number Order staff Verify measurements

15. Make a new staff? Not necessary 99% of time Need expertise on lathe Outsourcing is possible

19. Take measurements Hairspring hub Roller hub Pivots

21. Compare old to new Old staff New Staff Pivot Hairspring Roller Wheel

22. Modify if needed Reduce diameter of hubs using lathe. Choose another staff

23. Steps Remove hairspring Remove roller Remove balance wheel

24. Mark the postion of the stud

25. Mark Position Of collet

28. Mark position Of roller jewel

32. Remove wheel from staff Place staff in hole of table with wheel resting on the table. Push or tap staff out

33. Wheel is resting On table

34. Restaffing Place staff with roller side down in staking set. Choose appropriate round face and flat face punches. Place wheel over staff Rivet

39. Use round face first, then flat Turn punch while tapping Always use brass hammer Test In lathe

40. Replace roller Place on punch with hairspring side down “Three quarter” test Make sure jewel clears punch Tap or press on

41. Roller sits 3/4 th down