Dean May wrote: > Anecdotally, my experience is that marginal tuning pins are at their worst > in mid winter. I am aware of someone on this list experimentally proving > that holes shrink in dry wood. These two things seem contradictory. > > Perhaps the moisture content does more for gripping the pins than does the > actual interference fit. > > Dean In solid wood, the holes get bigger with humidity increase, and smaller with humidity decrease. Pinblocks are the reverse. The reason is the cross ply lamination. Dry: ( ) I I ( ) I I Damp: ) ( I I ) ( I I Friction coefficients do change with moisture, so that may well be a factor, but the primary mechanism is the restriction from the cross plies. Ron N
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