Mark: I recall the message(s) from Del and have read is recent posts and articles on epoxy on soundboards. One of the questions I have is how thick is too thick. Joe G. addressed this somewhat in his post. It suggests that a finish can be too thick and that a rubbery type finish applied too thick can reduce the function of the board. The consensus on all post is that the ultimate finish should be very thin and should dry relatively hard. I've encountered a piano recently that has a very heavy coat of varnish on it, fairly recently applied (1 year or so ago). The finish is still quite rubbery and flexes slightly to the touch. I don't know if it is over epoxy or not. The sound of the board is strange, weak with poor sustain though the board is showing some crown and positive but not excessive bearing. I did not hear the piano prior to the restringing so I don't have a way to compare but I am suspicious about the finish. Part of my question is wondering if this piano might not have a problem due to the thickness and flexibility of the finish. Though Del's research might have suggested that the types of finishes he applied within a relatively narrow range of thicknesses had no effect, that may not have been conclusive about how finishes improperly applied might not have a deleterious effect on soundboard performance. He has talked about the importance of stiffness in a board, but if you get that stiffness by adding mass there you could create a problem. If Del is reading this, perhaps he can comment. I am tempted with this particular piano to suggest stripping it down and scraping the finish off and replacing it with a thinner harder finish, but since I can't be sure of the results I can't do that in good conscience. My query with respect to violins was only because I know that violin makers seem interested in finishes with respect to how they effect sound. I was interested to hear from Gerald Posey on the subject. It sounds like a PhD thesis, however, and I can't go there right now. Many people, I notice, are using lacquer on soundboards these days. Lacquer dries quite hard, even brittle. Some varnishes, as Mr Posey suggests, remain quite flexible, others get much harder. Old finishes on soundboards are clearly quite hard as evidenced by how they respond when you scrape them off. In my own approach to soundboard finishing I have used varnish and never really thought that much about the type of varnish, how hard it gets, how thick is too thick or how flexible is too flexible. It may be that flexibility is not an issue until it gets too thick. Because of my recent experience, I thought that perhaps I should think about it more to avoid a potential problem. David Love davidlovepianos@earthlink.net > [Original Message] > From: <bases-loaded@juno.com> > To: <pianotech@ptg.org> > Date: 3/19/2003 1:17:47 PM > Subject: Re: Varnish on Soundboards > > David - > > Far be it from me to speak for Del, but I saved a message to Pianotech > from him some time back that told of the experiments he conducted with > different finishes on soundboards of similar new Baldwins back in his > Baldwin days, and the conclusion was that there was no appreciable > difference in tone quality, given reasonable and similar thicknesses in > various finishes (at least that's what I got out of it). My personal > speculation is that "needing the perfect elixir for the soundboard > finish" is just another of those voodoo tales that permeate the > instrument trades. I have been using water-based lacquer for soundboards > for the past 8-10 years with no discernible "loss in tonal quality". > That being said, personal testimonies seem a tad worthless, eh? Unless > one had multiple instruments of known similar quality, and the ONLY thing > different about each one was the soundboard finish, how would one > quantify results? THAT'S what struck me about Del's post.... seemed more > 'telling' to me than a hundred personal testimonials.... > > Mark Potter > bases-loaded@juno.com > _______________________________________________ > pianotech list info: https://www.moypiano.com/resources/#archives
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