In the 090408 MMD Randolph Herr was trying to locate a source for
a bellows spring, and he described a coil spring of a certain size.
Although most Wurlitzer band organs I have seen use leaf-type springs,
a couple of years ago I needed to replace a coil-type spring on a
Wurlitzer pressure reservoir.
I took the broken spring to a local spring company, and their head
spring maker did fabricate what I needed although, as I recall, it cost
a couple hundred dollars. He explained that it would take a trial or
two before he could get it right, and he offered to give me the trial
pieces. But I didn't take them.
Later on, I realized that European fairground organ makers like Johnny
Verbeeck usually use coil springs, not leaf springs, and I probably
could have gotten what I needed overseas. I suggest that Randolph Herr
look in that direction for one of their lighter springs. A fairground
organ spring would probably be too heavy for a piano reservoir.
Irondequoit, New York