I took the barrel piano over to the Repair Cafe event in Sheffield Today. It turns out Alan did a piano tuning course 40 years agoband still remembers enough of it to be able to give some excellent advice.
Also Gordon and I removed the key frame and found the stop that holds the keys from going too far was collapsing due to woodworm damage. Luckily the worm hav not eaten the main part of the key frame, so the bad timber strip was removed but kept as a template to make a new one. Girdon even came up with a nice piece of oak that was almost the right size without any cutting.
The piano is now back home with the keyframe cleaned up, ready for the new timber strip to be fitted.
The strip to be replaced appeared to have a felt edge where the hammer shanks hit against it. However on closer inspection the material turned out to be three layers of old sacking.
More restoration news to follow soon.