> I was not there, but a reputable tech told me about this. He had a NEW > grand piano with positive crown. The strings were removed and it still > had positive crown. The soundboard was remove, and it had negative > crown! What do you make of this? > > Frank Emerson This isn't unusual. I've seen a number of compression crowned boards with measurable crown (strings off) go concave when removed from the piano. The rim bevel holds bends thing into a crown, but there's no real load support. Also, there's no useful information here about the condition before unstringing. It had positive crown. Where, how measured, and how much? Bearing? Again, where, and how much? There are plenty of techs out there that will measure crown at the longest rib and proclaim the board to be good when six ribs up, the crown is deeply concave. Ron N
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