Pocket Watch Database

Rockford 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
18 340 6.2 1.35 1 0.64 1.2 Buy Now
If the Rockford 340 staff is unavailable, there might be interchangeable alternatives. See the interchangeable list.
18 341 6.15 1.4 1 0.64 1.25 Buy Now
If the Rockford 341 staff is unavailable, there might be interchangeable alternatives. See the interchangeable list.
18 342 (Short Hub) 6.15 1.38 1 0.64 0.69 Buy Now
18 343 (Long Hub) 7.05 1.25 0.92 0.64 0.75 Buy Now
18 344 (Short Hub) 7.05 1.25 0.92 0.64 0.71 Buy Now
18 522 6.35 1.25 0.87 0.64 0.67 Buy Now
If the Rockford 522 staff is unavailable, there might be interchangeable alternatives. See the interchangeable list.
18 585 6.08 1.25 0.87 0.73 0.6 Buy Now
18 880 6.1 1.25 0.93 1.15/.70 0.67 Buy Now
16 519 5.9 1.25 0.84 0.62 0.47 Buy Now
16 729 5.6 1.25 0.87 1.12/.68 0.44 Buy Now
16 739 5.55 1.25 0.87 0.73 0.46 Buy Now
If the Rockford 739 staff is unavailable, there might be interchangeable alternatives. See the interchangeable list.
12 61 4.6 1.04 0.63 .90/.55 0.42 Buy Now
6 521 Buy Now
4078 4.15 1 0.64 .73/.45 0.35 Buy Now
Data Source: Swartchild Balance Staff Charts and Company Material Catalogs
Pocket Watch Balance Staff Diagram