I want to thank all those who gave their input about my unseen customer's piano in which a plastic part broke "with a bang." I have finally seen the piano and broken part, and incredibly - the part that broke was a nylon pedal prop bolt! For the sake of terminology and clarity, this is, in 99.9999% of pianos, the small threaded metal rod that goes through a hole in the pedal, up through the pedal lever, and is topped off with a square nut or wing nut so the pedal can be adjusted. I find it amazing that a real company, with real engineers, would spend the money to make dies for this high stress part to be made out of plastic. They could have just taken that money and bought 50,000 traditional metal pieces. I have never seen a metal one fail. On the other hand, the nylon bolt did break at the point where a stray bubble was entrapped, an obvious moulding defect that effectively reduced the diameter of the bolt. Perhaps this is the only plastic pedal prop bolt that will ever break! I will save it for a museum. Thanks again to all for their input, B. Simon Phoenix P.S. - Expect to see foam rubber hammers soon.
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