> > Yesterday, January 9 made one week that my three flanges were exposed to 100% > humidity. I inserted the same 1/8" polished drill rod into each. All were a > little tighter than after two days. It was very difficult to insert the rod > into all three flanges. It appears clear to me that the center pin hole in > piano action flanges get smaller (decrease in diameter) as the reletive > humidity (RH) increases. I will let them dry at 50% RH for a week and see > whether they are the same tightness as when I first drilled them. I will then > dry them in a low-RH environment for a week and see what happens. I'll post > in a week or so. > > Any comments? > > Terry Farrell What the heck, why not? The fact that the rod is tighter in the hole means what? It means that the hole is possibly smaller overall, possibly narrower in one direction even though it's the same or wider in another - but that's not where I'm going. My thought is that if you can still push the rod into the holes, they couldn't have gotten all that much smaller - surely not enough smaller to have compressed a cloth bushing enough to seize a center pin enough to prevent it's rotation in the flange short of standing on it. Since it's unlikely that the pin swells that much either, that leaves either, or a combination of, the birds eye swelling and jamming between the flange ears (if they don't spread with the swelling of the flange body (another measurement test?)) and the bushing swelling. Ron N
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