English PW Balance staff English fusee

[praezis]

I have to change the mentioned balance staff (1st time this type). It looks like it is a simple straight or tapered staff. The balance spoke has a riveted brass sleeve that contains the staff.



How should I remove the old staff. If tapered, in which direction?
Thanks for help,

Frank

 

[Jerry Kieffer]

I have to change the mentioned balance staff (1st time this type). It looks like it is a simple straight or tapered staff. The balance spoke has a riveted brass sleeve that contains the staff.

View attachment 536695 View attachment 536696 View attachment 536697

How should I remove the old staff. If tapered, in which direction?
Thanks for help,

Frank

Frank
Based on the third photo, it appears that the staff could have only been installed from the bottom of the balance. I would remove the roller and drive out from the top of the balance down. I would also dimension the brass sleeve first, in case something really strange happens. It can then be easily remade.

Jerry Kieffer

 

[Jerry Kieffer]

Frank
Based on the third photo, it appears that the staff could have only been installed from the bottom of the balance. I would remove the roller and drive out from the top of the balance down. I would also dimension the brass sleeve first, in case something really strange happens. It can then be easily remade.

Jerry Kieffer

Frank
I am a little late on this , but on second look, it appears that the staff has a hub that the roller is seated on. If so, it would then be difficult to support the brass sleeve when removing the staff. This can be resolved by using a staking tool roller removing accessory per attached photo. The arms can reach behind the hub and support the sleeve.

Jerry Kieffer

 

[praezis]

Jerry,
thank you for being engaged in my problem and for your hints!
After posting I found that exactly my question had already been answered in 2015 here.

Both of you advised to push the staff to the bottom. My measurement however showed a staff diameter of 0.56 at the upper end of the brass sleeve and 0.55 at the lower end. Assuming a straight tapered staff I was tempted to push it to the top, but no movement.
Eventually I could remove the staff to the bottom.


A strange double tapered staff appeared: the part in the brass sleeve was roughly square shaped.


In advance I had removed the roller that came loose with a nasty frightening cracking noise, but there was no damage in any way.


Hours later this work was finished.


Frank

 

[Jerry Kieffer]

Jerry,
thank you for being engaged in my problem and for your hints!
After posting I found that exactly my question had already been answered in 2015 here.

Both of you advised to push the staff to the bottom. My measurement however showed a staff diameter of 0.56 at the upper end of the brass sleeve and 0.55 at the lower end. Assuming a straight tapered staff I was tempted to push it to the top, but no movement.
Eventually I could remove the staff to the bottom.
View attachment 536947

A strange double tapered staff appeared: the part in the brass sleeve was roughly square shaped.
View attachment 536949

In advance I had removed the roller that came loose with a nasty frightening cracking noise, but there was no damage in any way.
View attachment 536948

Hours later this work was finished.
View attachment 536950

Frank

Frank
I am happy it worked out for you. It looks great.

The most unusual staff I have ever had, had a roller that was one piece to the staff itself with a triangle roller jewel in a triangle hole.

In this case, if you did not have a staff, I am assuming that you machined or cut a replacement staff. Personally, if it had ran true when chucked on the square, I may have been tempted to repivot it as it appears to have the dimensions that would support such a repair.

Jerry Kieffer

 

[praezis]

Jerry,
yes I made a new staff.
0.11 mm pivots are beyond my drilling possibilities, my limit is 0.20.

Frank

 

[Jerry Kieffer]

Jerry,
yes I made a new staff.
0.11 mm pivots are beyond my drilling possibilities, my limit is 0.20.

Frank

Frank
Micro drilling is of course another topic by itself.

In this case, I would have also machined a new staff due to its basic design. However had I repivoted it for whatever reason, it would have been done per the attached sketch.
When repivoting, I rarely Repivot the actual size of the pivot, but some what larger. I then machine down too size that assures a round straight pivot centered to the staff or whatever.

Jerry Kieffer

 

[praezis]

Jerry,
I know that micro drilling is one of your favorite topics and I like your postings and amazing ideas.

Recently I had to replace twice the pallet staffs of PWs as above. One got the pivot drilled, the other staff was turned. I found the drilling not so much faster than the other method. With all the involved extra work amazingly it always takes twice the time that I expected before.

Frank

 

[Jerry Kieffer]

Jerry,
I know that micro drilling is one of your favorite topics and I like your postings and amazing ideas.

Recently I had to replace twice the pallet staffs of PWs as above. One got the pivot drilled, the other staff was turned. I found the drilling not so much faster than the other method. With all the involved extra work amazingly it always takes twice the time that I expected before.

Frank

Frank
I would agree that a typical pallet arbor can be turned or machined in about the same time as repivoting. Personally, I only repivot where original strength, accuracy, appearance and function can be maintained while minimizing time and effort.

Jerry Kieffer