Hi All.  I am restoring a set of bellows for a 1921 Adam Schaff piano
with an Amphion player action.  I am following a restoration done about
30 years ago and have a question regarding the spans.  The bellows have
a 6" span on both, which seems normal.  However, one of the reservoirs
has a leaf spring with a span of 4.5" and the other has a coil spring
with a span of 3".

Although I have only restored a handful of bellows in my day I have
never seen two reservoirs with two different spans.  To you major
restorers, is this common or was there an error made by the previous
restorer?

Thanks,
Curt Clifford