>I've been tuning pianos for 7 years. I'm not unaccustomed to rendering problems. But this is the only time I've been defeated by a piano like this. Tuning pin tightness is good, except for a couple. The bridge is not loose. The plate is not cracked. The upper termination point for the tenor and treble strings is not a cast surface, but a long cylindrical rod in a groove on the plate. The unisons agree with each other, but whole ranges of notes simply will not stay where I put them, even after multiple passes. I was unable to diagnose the problem. What am I missing?"< Floyd - This situation reminds me of a Fischer grand I worked on years and years ago. It was a really strange thing - every time I went over the treble the bass went drastically out of tune and vise-versa. Pulling the action and inspecting the fit of the pinblock against the flange in the cast iron plate with a mirror I could see that it wasn't a tight fit, but not much more. I went out on a limb and told the owner that I thought there was a problem with the pinblock not seating firmly against the flange, and recommended replacement. Thankfully, when I pulled the plate for a closer look, I found that the pinblock in fact only touched the flange in 3 spots, but importantly not all 3 at the same time. It was like a teeter-totter, with the middle spot always in contact, but the outer 2 touching only 1 at a time, depending on which way the block was being pulled. Great job of fitting at the factory! When the block shifted, the dynamics of tension would change on both the treble and bass end of the piano, thus making it impossible to tune. A vertical piano, of course, has a different type of pinblock construction, but I'm just wondering if some similar fault might exist. Chuck Behm -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://ptg.org/pipermail/pianotech.php/attachments/20100614/ac071840/attachment.htm>
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