Dear Brent, Thank you for your kind remarks and interest in the article. As you pointed out the views I have expresses in this article are one sided and unlike those usually seen on this list lacking the usual give and take. This is as it should be since I wrote the article to be published in my news letter which is designed to market my rebuilding business. In spite of my warnings that this material is too commercial in content for the list the list’s director (Vince Mrykalo) requested it’s inclusion. I my also point out that this article was meant for local consumption here in the New York and greater new England area where most of my business comes from and I was deliberately highlighting aspects of my work that set me apart. Even though the quality of rebuilding in the New York area is generally considered excellent I have always felt that many aspects could be improved. This idea is the impetus for my own business to provide a better grade of piano rebuilding. I am not suggesting that my methods be adopted I only wish to inform prospective clients of the available choices. Your comments about soundboard panels are well placed. I am sure there are panels available suitable for most piano rebuilding. At the time I set up my panel making process I could not persuade any of the commercial sources to make them to my standard. Besides the usual problems such as quarter sawing, rings per inch, width of individual boards, wood species and appearance I found it impossible to get them to use hide glue. Another demand was that the wood be stored in a interior space for at least one year before being made into panels. This was the practice of instrument makers in the past and I think it is a good idea. This is done for the stabilization of stresses in the wood. Most of the wood I use is over two years old and stored in a loft over my work areas. I certainly think highly of Andre Bolduc and the panels he produces and I often recommend them to technicians but I don’t think that these would be the equivalent of the ones I make for myself. I don’t know if he is using hyde glue. If he is, he should advertise it. Knowing how much space it takes, I doubt if the wood is handled in the way I described above; it would be just to costly for a larger commercial enterprise. There is one other aspect I would point out; at present Bolduc offers only eastern spruce. I keep on hand both eastern and sitka spruce. In my experience Steinway grands require sitka spruce to achieve full power. This is particularly important for larger instruments. On the other hand a beautiful darker tone quality is found form using eastern spruce but with less power. I like to use eastern spruce on some of the Mason and Hamlins. Now lets get back to our debate on ridges and cracks. First of all lets decide that there indeed exists a phenomenon where the surface of the soundboard develops over time areas raised above the level surface of the soundboard. These raised areas are formed in the direction of the grain usually but not always at or near a glue line. The affected area is anywhere from one to twelve growth rings in width and may extend fully or partly the length of the soundboard. The affected area may or may not extend to the under surface. These raised areas may or may not develop into cracks over time. Let us call these soundboard ridges. Brent, you pointed out in your post the need to define when a soundboard ridge is significant or not. I would like to propose a line of reasoning that may help. If we have adopted the above definition then we agree that ridges are areas where wood has displaced a degree above the surrounding surface. At what point is this displacement significant enough to indicate permanent damage to the wood? My I suggest that we use the one percent rule. I refer you to “Understanding Wood” by R. Bruce Hoadley page 114 were he describes when wood is deformed by more than 1 percent it is permanently changed. The one percent rule is a rough approximation but fits spruce rather well. This permanent change known as “set” indicates that cell damage has begun to happen and the wood in the area is weakened. So how high a ridge should we be concerned about? Soundboard panels are generally between 1/4” and 3/8” in thickness. Taking the average of 5/16” equaling .3125” we arrive at .003” as one percent of the soundboard’s thickness. Can we take this as a rough approximation of the degree of ridging above which permanent damage will happen? Even if we double this figure for the sake of argument we have a rather small number somewhere between a pink and green front rail punchings. When I see soundboard ridges of these sizes I am at least concerned knowing that small problems often lead to larger ones later on. If I can see a ridge or ridges from across the room I am alarmed. As you pointed out pianos may sound better if subjected to plenty of compression, and this I agree with. But how long will the board maintain that compression if signs of wood failure are found early in the life of the piano? Is it possible to develop soundboard building techniques that will minimize these problems? I think so since it is obvious that we can make mistakes to aggravate them. I think this is an important issue that requires careful study. I’m sorry but calling this problem raised grain just doesn’t satisfy me. Respectfully, John Hartman
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