How balance staffs are replaced Ken Pell


Download 445 b.
Sana17.07.2017
Hajmi445 b.
#11447



How balance staffs are replaced

  • Ken Pell



Components of balance assembly

  • Wheel (split or solid)

  • Staff (riveted or friction)

  • Hairspring (flat or overcoil)

  • Roller (single or double)









Why they must be replaced

  • Trauma, such as dropping or bumping watch which damages the staff and jewels







Pre staffing

  • Clean movement

  • Examine and replace balance jewels

  • Identify movement early and secure new staff









Selecting replacement staff

  • Determine grade of watch

  • Use Elgin reference for staff number

  • Order staff

  • Verify measurements



Make a new staff?









Take measurements

  • Hairspring hub

  • Roller hub

  • Pivots





Compare old to new



Modify if needed

  • Reduce diameter of hubs using lathe.

  • Choose another staff



Steps

  • Remove hairspring

  • Remove roller

  • Remove balance wheel



















Remove wheel from staff

  • Place staff in hole of table with wheel resting on the table.

  • Push or tap staff out





Restaffing

  • Place staff with roller side down in staking set.

  • Choose appropriate round face and flat face punches.

  • Place wheel over staff

  • Rivet











Rivet

  • Use round face first, then flat

  • Turn punch while tapping

  • Always use brass hammer

  • Test In lathe



Replace roller





















Download 445 b.

Do'stlaringiz bilan baham:




Ma'lumotlar bazasi mualliflik huquqi bilan himoyalangan ©fayllar.org 2024
ma'muriyatiga murojaat qiling