Right... Regarding the "rasten", I'd like to take a step back, and come at this from a "what is physically possible" perspective. For the moment lets leave all design intent aside and look at this from a what is physically possible perspective. The question is "what are rebuilders actually achieving when they do this, as opposed to what do they think they are achieving". To be clear, I'm not talking about tonal results here. I'm simply talking about whether, if one of us said they were going to bevel so-and-so piece of wood at such-and such angle, they actually did what they set out to do...ie the "as built" wooden joint matched their intent. As someone with a background in setting up production runs where hundreds of 5 surface profiled joints had to fit dead nuts without hand adjustment, I had to learn how to prove what I was actually achieving in a particular process rather than assuming that I had achieved what I set out to achieve, wished to achieve, or though I achieved. Learning how to prove the "as built" conditions is a challenging task, much harder than one would expect, until one learns how to create and maintain trustworthy indexes. For any of us the "as built" and the intent can sometimes be wildy different things. Further, its hard enough to match intent to result in set ups where the parts are all straight lines, but with a piano where straight lines are few and far between, and joints are cut in tough to access places, its a whole other kettle of fish. I find this tug between intent and achieved results again and again in piano work. In this work the tug is accentuated because there simply is not a trustworthy reference point or index surface to be had, unless one purposely sets out to create and prove one, and then refer and correct all work back to that known index. So my take on this is, given my background, simply that the mating angle at the "rasten" is highly variable both from the rim's and the panel's perspective and thus unknown in its "as built" reality. At least from a rebuilder's perspective, the rasten joint is physically impossible to actually achieve with the intent techs claim they are shooting for. It only introduces complexity where the complexity takes on a mind of its own. I see the added complexity trying to control such a miniscule detail becoming gratuitous, and even worse fueling speculations about what one achieved without proving that one actually created the intended physical joint. This in addition to whether there is any tonal advantage at all in theory. However this is hypothetical anyway, because probably its never actually been accomplished. Add to this, that the majority of the "rasten" is along the short extremely flexible grain of the panel, and the claims of its value become more and more questionable. Jim Ialeggio -- Jim Ialeggio jim at grandpianosolutions.com 978 425-9026 Shirley Center, MA
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