Rob, Many of he Baldwin acros of the 60's -70's have chronic tight centers . My first test is to depress the left pedal , release quickly and watch for slow hammer return. Jacks centers can also be tight .I use the age old alc-water shrink-sizing method and it seems to provide a permanent fix. Give it overnight and test. Some use a hair dryer to speed things up but I'd rather see what the center will do on it's own. I then shoot some protek figuring it can't hurt to slick the center up. I realize that not every piano will respond ( I.E. center pin plating problem on the Samicks) but with this Kimball I would give it a try. It's easy ,cheap and will do no harm AND it might solve the problem. Just my take, Best wishes, Tom Driscoll----- Original Message ----- From: "Rob McCall" <rob at mccallpiano.com> To: <pianotech at ptg.org> Sent: Sunday, July 31, 2011 2:28 AM Subject: [pianotech] Guess which pin... > Greetings, > > I have a 1982 Kimball Console action in my shop. Many of the keys were > sticking in the piano. Looking at it in the piano, the problem didn't > appear to be the keys, at all. It was definitely in the action. However, > it was difficult to tell which center pin it was. At first it looked like > the hammer butt flange pin needed to be re-pinned. So I did that. It > fixed it momentarily. Then it started to stick again. Looking at it, it > looked like the wippen center pin might be the problem since it wasn't > coming all the way back down when the key was released. Although, I wasn't > clear if it was because the jack center wasn't resetting all the way, > either. As the problems were over the entire upper third of the action to > one degree or another, we agreed to have me take the action and work at it > on my bench. > > As it turns out, about 30 percent of the hammer butt flanges needed > re-pinning. Also, about 20 percent of the jack centers had to be > re-pinned. Additionally, almost 50 percent of the wippens needed to be > re-pinned. It was hit and miss, with some notes needing all 3 pins > changed, others 2 pins, and some only 1 pin, while some remained > unchanged. I ended up taking pretty much every hammer and wippen assembly > off to evaluate all 3 pins. > > It seemed very time-consuming, so my question is this... > > What do you look at, or manipulate, to determine which pin is the culprit > while the action is still in the piano or on the workbench? How do you > test them all to determine the troublemaker without disassembling most of > the action? > > Obviously, my method works very well, but, as I mentioned, it's very > time--consuming. Any thoughts or insight is greatly appreciated. > > Regards, > > Rob McCall > > McCall Piano Service, LLC > www.mccallpiano.com > Murrieta, CA > 951-698-1875
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