Last month I was regulating a Steinway upright, and I tried to take the lost motion out by raising the capstans. The jacks wouldn't come back unless I left too much lost motion. I first tried the standard things. I checked the action centers and the key bushings for smooth movement. I tightened up the jack springs, and loosened the butt springs. These things didn't help. I spoke to Michael Slavin and my brother for additional possible ideas. Rob said, "It could be a build-up of several factors like the ones we talked about last night. For example, the unusual key weight you mentioned, plus slightly tight key bushings or corroded pins, plus corroded spoons or indented cloth at the spoon or capstan, plus slightly tight center pins. Each one might not be enough to cause the problem but added together they could cause it. What about extremely indented and crusty hammer rest rail cloth with slightly loose pinning in the butts? I wonder if that could contribute". This wasn't the case.

They both had great suggestions; Michael said to check the back check and bridle wire adjustments, but they were both good. He also told me to check the buck skin on the butts for excessive wear. I had already checked that by eye, without taking them out. I decided it would be a good idea to get a closer look, and take a few butts out. When I pressed on the buck skin, at the area that makes contact with the jack, I noticed that it felt very soft and lumpy. I also noticed that the buck skin was cut too long and it was butted up against the catcher shank.

The buck skin wasn't stretched tight; it couldn't have been, because it was too long. I cut the buck skin, just on that side with a razor blade, and then I trimmed a little piece off of it. I stretched it and glued it back. Now there were no lumps, and it wasn't soft anymore. The capstans were able to be adjusted properly. It is good to know great technicians, with a world of knowledge.