Fitted New Balance Staff & The Impulse Roller Hole Is To Big.

[Legarm]

Hi all,

Fitted new Balance staff to the balance wheel & the impulse roller hole is to big. This on an Elgin 559 Lord Elgin movement. The balance staff was purchased from Cousins, under their Branded parts. The balance staff is a perfect length and runs perfectly in-situ. 

Any ideas on how to make the impulse roller fit?

Thanks 

Keith