My humble two cents about this plate growing thing. I think it is not the plate that is growing but the pinblock. The tuning pin bushings are usually tighter in the bottom of the hole (for an upright) than the top. Depending on the block (multi-ply or maple) and on the tuning pins placement (read measurement differences between the top and bottom pin), the block may very well grow enough to explain this unison thing. Maybe I'm right, or then maybe I'm wrong, but it sure makes sense to me. Marcel Carey, RPT Sherbrooke, QC
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