Broken jack springs

[Cedar Mill Piano Tuning]

Dear Pianotechies,

I have a customer with a Story and Clark console.  Back in 1980 a technician
left a record of having to replace a broken jack spring.  The customer tells me
that several have broken since then, and now she has two more that are broken.
Fortunately, she realizes, even suggested herself, that they should all be
replaced, so I'll be doing that job.

But I have a question -  Why would the jack springs be breaking in the first
place?

Any advice as to which glue is best for jack springs?  Anyone got a handy
method of snapping new jack springs into place?  I'm hoping that a drop of
deglueing solution (wallpaper remover in water) will loosen the old ones.

Larry Goss
Cedar MIll, Oregon