Dear Audrey and List, I had to repair a fairly new vertical piano one time which had poor repetition due to improper key weighting as you described. In this case, the hammer return springs were very strong, and the keys had apparently been leaded to achieve some target downweight, resulting in much lead in the front side of the keys. Problem was, the key and wippen could barely return to rest without the help of the hammer spring, which they do not have in normal playing. It felt horrible, even though the regulation and friction levels were fine. To remedy the problem, I removed most of the leads, then weighed off the keys so that each key / wippen combination had an upweight of (if I remember right) 15 grams with the hammer held out of the way. This assured that these parts could return easily under playing conditions. I then weakened the hammer return springs to achieve an agreeable downweight, something like 46-48 grams. This fixed the problem; it felt great and repeated well. To diagnose your piano: test to see if a given key with it's wippen sitting on it (but not the hammer) can lift at least 12-14 grams back to rest position when depressed. If it cannot, key reweighting will be the answer. All of the above assumes that there are no excess friction problems anywhere, and that the sustain pedal is depressed or blocked so the damper spring cannot help the wippen return. Steve Schell stfrsc@juno.com
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