<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> <HTML><HEAD> <META content="text/html; charset=iso-8859-1" = http-equiv=Content-Type> <META content="MSHTML 5.00.2919.6307" name=GENERATOR> <STYLE></STYLE> </HEAD> <BODY bgColor=#ffffff> <DIV>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.</DIV> <DIV> </DIV> <DIV>Any comments?</DIV> <DIV> </DIV> <DIV>Terry Farrell<BR>Piano Tuning & Service<BR>Tampa, Florida<BR><A = href="mailto:mfarrel2@tampabay.rr.com">mfarrel2@tampabay.rr.com</A></DI= V> <BLOCKQUOTE style="BORDER-LEFT: #000000 2px solid; MARGIN-LEFT: 5px; MARGIN-RIGHT: = 0px; PADDING-LEFT: 5px; PADDING-RIGHT: 0px"> <DIV style="FONT: 10pt arial">----- Original Message ----- </DIV> <DIV style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: = black"><B>From:</B> <A href="mailto:mfarrel2@tampabay.rr.com" title=mfarrel2@tampabay.rr.com>Farrell</A> </DIV> <DIV style="FONT: 10pt arial"><B>To:</B> <A = href="mailto:pianotech@ptg.org" title=pianotech@ptg.org>pianotech@ptg.org</A> </DIV> <DIV style="FONT: 10pt arial"><B>Sent:</B> Friday, January 05, 2001 = 10:31 PM</DIV> <DIV style="FONT: 10pt arial"><B>Subject:</B> Results are In! Re: = moisture in wool or wood.</DIV> <DIV><BR></DIV> <DIV>Tuesday, January 2, I started my hole in wood experiment to see = if a hole will get smaller in diameter or larger with increased humidity. Rather = than drilling holes in wood that may or may not reflect what happens with = an actual flange, I took three old flanges lying around my shop. One was an = grand damper flange, one an upright hammer butt flange, and one was a grand hammer = shank flange. All were likely in the 40 to 80 year old range, and all = had been sitting in my shop in 40% to 50% reletive humidity (RH) for months. I = drilled out the flange bushings with a 1/8" drill in my drill press, being = sure to keep things square. I cut three pieces of 1/8" drill rod for center = pins. I filed the ends and polished the rod/pins so that they were nice and = smooth. All three rods/pins fit into the flanges real easy by hand, but had no = slop. My pinky could easily push them in and out with little effort.</DIV> <DIV> </DIV> <DIV>Since Tuesday the flanges have been sitting on a little plasitc = platform in a tupperware box with a little water in the base. The flanges have = not touched the water, but rather have been exposed to 100% humidity for = three days. The center pin for the damper flange fits noticeably tighter, = but was no trouble pulling it out with fingers. The butt flange was tighter yet. = And the grand hammer shank flange was very tight, I could just barely push it = in and get it back out - VERY tight.</DIV> <DIV> </DIV> <DIV>It would appear to me that the hole in a wooden flange decreases = in diameter with increasing humidity. Am I wrong? </DIV> <DIV> </DIV> <DIV>I'm gonna wait a whole week and then check them again. After that = I will dry them out real good and slow and check them under very dry conditions.</DIV> <DIV> </DIV> <DIV>Terry Farrell<BR>Piano Tuning & Service<BR>Tampa, = Florida<BR><A = href="mailto:mfarrel2@tampabay.rr.com">mfarrel2@tampabay.rr.com</A></DI= V> <BLOCKQUOTE style="BORDER-LEFT: #000000 2px solid; MARGIN-LEFT: 5px; = MARGIN-RIGHT: 0px; PADDING-LEFT: 5px; PADDING-RIGHT: 0px"> <DIV style="FONT: 10pt arial">----- Original Message ----- </DIV> <DIV style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: = black"><B>From:</B> <A href="mailto:DonMannino@mediaone.net" title=DonMannino@mediaone.net>Donald Mannino</A> </DIV> <DIV style="FONT: 10pt arial"><B>To:</B> <A = href="mailto:pianotech@ptg.org" title=pianotech@ptg.org>pianotech@ptg.org</A> </DIV> <DIV style="FONT: 10pt arial"><B>Sent:</B> Monday, January 01, = 2001 10:56 PM</DIV> <DIV style="FONT: 10pt arial"><B>Subject:</B> Re: moisture in wool = or wood.</DIV> <DIV><BR></DIV><FONT size=3>Terry Farrell wrote:<BR> <BLOCKQUOTE class=cite type="cite" cite>I have heard/read this = many times, so I suppose it is true. But, intuitively, it makes no sense to = me. If you drill a hole in a piece of wood and expose it to high humidity, = the wood will swell - and swell much more across the grain (perpendicular = to the grain direction) than with the grain. So why doesn't the hole tend = to close a bit - on the two sides of the whole where the tangents are = parallel to the wood grain.</FONT></BLOCKQUOTE><BR>Because the = whole piece of wood swells, and the hole becomes larger along with the piece of wood.  As I wrote in my last post, imagine the plug of wood = which used to be in the hole.  The hole behaves the same as the plug of = wood that was taken out.<BR><BR><FONT size=3>Do the hole and rod = test.   Just pick a small piece of maple or something, soak it in water for = a while,  then drill a hole in it with a spare drill.  After = drilling, put the drill back in the hole, then dry the wood in the oven!  That drill will be really nasty tight in the hole!  = You'll have to soak the wood again to get it out.<BR><BR>There are some = exceptions to this behavior:<BR>1. In some situations the surface fiber = swelling in the hole exceeds the change in shape of the wood.  Key balance = holes are examples of this, where high humidity sometimes tightens the = fit.  The wood thickness is small, and the wood fibers are large and sometimes = made of more reactive wood.<BR>2. Cross-laminated wood is more dimensionally = stable, and the surface fibers will again have more affect on the hole size = than the dimensional changes of the wood.  This is what happens in pinblocks.<BR>3. If the hole was made by compression of the fibers = instead of by drilling and removing wood (like with a nail) then the grip on = the nail is tighter during humid times.  All surface fiber effect, = no hole to swell.<BR><BR>Don Mannino RPT<BR><BR></BLOCKQUOTE></BLOCKQUOTE></FONT></BODY></HTML>