Not to fret Cy You are not the only one to be confused by this. Personally, I could swear that pins get looser in the pinblock during the dry season.... and this contradicts Kens information. But I will be the first to admit that I have never actually gone and put a torque wrench on tuning pins season in and season out, year in and year out to make sure. All that being said... it would seem to me that the 32 % RH figure that our tail banging associate waggled around a day or so ago would seem reasonable enough one way or the other. Its on the low end of what is reasonably acceptable variance in RH anyways. Heck.. if all piano room climates never fell below 30% RH and never exceed 60 % ...... :) .... but things dont usually work out that stable. RicB Cy Shuster wrote: > OK, I know we've all been over this, but as a newbie associate I just have > to ask. When we apply an alcohol/water mixture to bushings to free up tight > action centers, doesn't that work by making the wood swell up around the > pin, compressing the felt? And then when the alcohol helps the water > evaporate, the wood shrinks back? (Or do I remember this backwards: do we > do this to bushings to tighten up loose ones?) > > And wouldn't a one-foot plank of wood get longer (and bigger in each outside > dimension) as it expands, when soaked? Are you saying the outer edges would > move away from each other, but the walls of the holes would also expand > towards the outer edges? What if you drilled a hole near the edge and sawed > it off through the center of the hole? Would the straight edge move outward > from expansion, and the curved wall of the hole move inward? > > Just trying to understand this -- I know it's counterintuitive! Thanks. > > --Cy Shuster-- > PTG Associate Member > Rochester, MN > > > --- Ken Jankura <kenrpt@earthlink.net> wrote: > > > Dear Thump, > > > OK, one last time, all together now, holes in wood > > > act as wood itself would > > > act. Fact. Truth. Take it to the bank. > > > A FINGER-SIZE HOLE IN WOOD WILL GET BIGGER WHEN WOOD > > > IS PLACED IN WATER. > > > One note of exception - the hole will initially get > > > smaller as water enters > > > the wood fibers and cells and spaces by the cut > > > edges. But upon equilibrium, > > > you'll wonder why you drilled the hole so big. > > _______________________________________________ > pianotech list info: https://www.moypiano.com/resources/#archives -- Richard Brekne RPT, N.P.T.F. UiB, Bergen, Norway mailto:rbrekne@broadpark.no http://home.broadpark.no/~rbrekne/ricmain.html
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