Had a similar situation with a piano on the dealer show floor. The way that it was detected was that when the rims separated, the split must have been in one of the outer laminations of the inner rim. It could be seen from the top as a tearing apart of the sound board at the tail where part of the soundboard was still attached to the outer edge of the inner rim and the other part was still attached to the inner part of the inner rim. On looking at the piano from the bottom, the crack could be seen to have gone all the way through. That piano got sent back to the manufacturer. Rex Roseman
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