Pocket Watch Database

Hampden Balance Staffs

The delicate balance staff is one of the parts most frequently destroyed when a watch is dropped or sustains a forceful blow. The tiny pivots on each end of the balance staff are prone to bend and sheer under unreasonable force. When the balance staff is broken, it must be replaced by a staff matching the same dimensions as the original. If a factory-sized staff cannot be purchased, one must be fabricated using a watchmakers lathe.

When purchashing a replacement staff, pay attention to the avialable pivot sizes available. Many manufacturers also slightly modified the staff simensions, leading to some part number available in different variations (small/large collet, old/new style, short/long hub, etc). Keep this in mind when evaluating the avaialble staffs for a watch movement. It is recommended that the old staff be removed a measured prior to purchasing a new staff. Replacing a staff is a skilled operation requiring special tools. Please contacts a reputable watchmaker that specializes in antique watches if you are not equipped to replace a balance staff.


Movement Size   Part Number   Length (mm)   Balance Seat (mm)   Hairspring Seat (mm)   Roller Seat (mm)   Hub (mm)   Pivot Sizes   Image Purchase on eBay
18 1720 (Old Style) 5.83 1.27 1 0.77 1.27 Buy Now
18 1721 (New Style) 5.83 1.27 0.77 0.7 1.23 Buy Now
If the Hampden 1721 (New Style) staff is unavailable, there might be interchangeable alternatives. See the interchangeable list.
18 1722 5.85 1.27 0.77 0.71 1.03 Buy Now
16
Models: 1890
2720 (Old Style) 5.6 1.27 0.76 0.71 0.65 Buy Now
If the Hampden 2720 (Old Style) staff is unavailable, there might be interchangeable alternatives. See the interchangeable list.
16
Models: 1902
3720 (New Style) 5.13 1.27 0.75 0.71 0.57 Buy Now
12 6720 (Old Style) 4.8 1.2 0.76 0.6 0.47 Buy Now
If the Hampden 6720 (Old Style) staff is unavailable, there might be interchangeable alternatives. See the interchangeable list.
12
Models: 1910
7720 (New Style) 4.67 1.22 0.76 0.57 0.43 Buy Now
If the Hampden 7720 (New Style) staff is unavailable, there might be interchangeable alternatives. See the interchangeable list.
12 12720 3.33 Friction 0.74 0.57 Friction Buy Now
6 8720 4.4 1.22 0.75 0.6 0.34 Buy Now
If the Hampden 8720 staff is unavailable, there might be interchangeable alternatives. See the interchangeable list.
3/0 9720 3.95 1 0.66 0.57 0.37 Buy Now
If the Hampden 9720 staff is unavailable, there might be interchangeable alternatives. See the interchangeable list.
3/0 10721 3.64 1 0.66 0.57 0.32 Buy Now
Data Source: Swartchild Balance Staff Charts and Company Material Catalogs