The Haseldine movement has a broken balance staff, and the balance wheel and bridge are removed.
Here the bottom of the balance wheel. A much large balance, and a perfectly spiral hairspring without any bends to the external loop.
The escapement bridge, wheel and lever.
The escape wheel has a special recess in the movement that I have encountered only very infrequently. This is to reduce the overall thickness.
Balance bridge and wheel.
Diamond balance staff end jewel. Both the cap and pivot jewels are in good condition.
Detail of the escape wheel (showing through the number of teeth and pinions, that it beats at a frequency of 18,000 bph).
Recording the position of hairspring stud in order to guarantee the same timing when the new staff is fitted.
Similarly, recording the position of the roller table, to ensure accurate timekeeping.
Another view of the balance.
Here a profile image showing the broken top balance pivot.
The top diamond end-stone removed, the pivot jewel is in excellent condition.
Hairspring removed. This balance also shows a replacement staff with the brass bushing.
Examining the height of the roller table. Which should normally sit against the bottom balance seat (here there is a gap).
Removing the roller table on a tool for this purpose.
Roller table removed.
Staking the balance out.
Balance removed, the brass seat is next.
Staff, balance wheel and staff bushing.
The balance staff is sized.
Measurements to create a new balance staff by hand.