The theory is the epoxy penetrates the wood and fills the cells. The wood cells act as a matrix for the epoxy, this is what Del spoke of in the articles. And it does make some sense. So it is not a thin layer of epoxy riding on top of the wood that is providing the stiffness and strength, but the whole matrix of the wood cells reinforced and filled by the epoxy. I am planning on trying this out soon and my intent is to epoxy both sides of the board. I would think that the cells penetrated by the epoxy would be resistant to any subsequent moisture effects. Dean Dean May cell 812.239.3359 PianoRebuilders.com 812.235.5272 Terre Haute IN 47802 -----Original Message----- From: pianotech-bounces@ptg.org [mailto:pianotech-bounces@ptg.org]On Behalf Of Farrell Sent: Wednesday, October 20, 2004 8:57 AM To: Pianotech Subject: Re: Epoxy on soundboards If the epoxy actually prevented the top of the panel from expanding, perhaps with added moisture, the soundboard would want to invert! But the ribs would fight it (if rib crowned). So maybe it would just implode (stand back!). But how would a thin coating of epoxy keep the top surface from expanding? I don't know what the tensile strength of a thin coat of epoxy is, but I'd but it's not much. Indeed, I do imagine that it would constrain the top of the panel a bit, but seems hard to imagine it doing lots. Keep in mind we are not applying a layer of woven glass cloth on the top of this thing. My guess is that the board would respond to changes in MC much like an uncoated board, but perhaps a bit less so. Just my guess. Did you get the article David? Terry Farrell ----- Original Message ----- From: "David Love" <davidlovepianos@comcast.net> To: "'Pianotech'" <pianotech@ptg.org> Sent: Wednesday, October 20, 2004 9:24 AM Subject: RE: Epoxy on soundboards > I don't know exactly, but the epoxy presumably penetrates the board a > fairly small amount on the top. So the lower part of the panel will > want to expand as it takes on moisture. So as the lower part of the > panel is wanting to expand, but the top of the panel is held rigid, what > will happen? > > David Love > davidlovepianos@comcast.net > > -----Original Message----- > From: pianotech-bounces@ptg.org [mailto:pianotech-bounces@ptg.org] On > Behalf Of Ron Nossaman > Sent: Wednesday, October 20, 2004 6:02 AM > To: Pianotech > Subject: RE: Epoxy on soundboards > > > >Here's my real question: If you dry down the panel and wedge it up, > >then epoxy it and let it cure while the board is still in a dry state > >and then allow it to take on moisture, will the panel crown a bit as it > >takes on moisture? > > > >David Love > > > I haven't measured, so I don't really know, but I doubt it. If the top > of > the panel is constrained from expansion by the epoxy, what would supply > the > leverage to lift the crown? > > Ron N > > _______________________________________________ > pianotech list info: https://www.moypiano.com/resources/#archives > > > _______________________________________________ > pianotech list info: https://www.moypiano.com/resources/#archives > _______________________________________________ pianotech list info: https://www.moypiano.com/resources/#archives
This PTG archive page provided courtesy of Moy Piano Service, LLC