At 04:06 PM 2/4/2005 -0800, you wrote: >(Maybe Susan has a copy?) Susan JUST HAPPENS to have a copy -- not having a son to "tidy up" my files, I have been able to go right to it. Of course it helps that this post dates from 1997, back when I still took the time to sort and organize. Back then I thought that if my In Box had 300 posts I was way behind. I had yet to discover that Eudora can handle 5000+ posts in a box and (usually) not tangle or lose any. Sometimes I wish she WOULD lose some ... Best, Susan ************************************************************************** In November, 1997, Horace wrote (to Avery): ************************************************************************** NY and Hamburg pianos require very different approaches, depending on the period of manufacture. Some background: Prior to W.W.II, both factories manufactured instruments that, while different in certain ways, were virtually identical in others. So much so that from the earliest period of the re-establishment of manufacturing in Hamburg, NY was shipping everything from action parts to completed pianos to London and Berlin, as well as Hamburg. Yes, parts came this way as well, and not all models were consistently produced in both plants. The destruction of the Hamburg facilities through the firebombing of Dresden and Hamburg during W.W.II created a real problem. With the end of the war, NY had its own problems, and insufficient reserves to rebuild in Germany. Enter Louis Renner, et al. Renner offered to rebuild the facilities in Hamburg. There was, of course, a catch. The catch was that Steinway would have to use actions, back actions, hammers, and other parts from Renner. This began the real divergence between the two branches of the company. The Renner parts, while generally conforming to NY specifications, actually were (are) quite different. The reasons do not matter, the matter just is what it is. The results are the differences of touch and tone which we have come to expect from the two factories. What then, are these differences? Let's start with NY. The following general procedure was in use up through, roughly, the 1987-1988 production period. First, the location of the keyframe and cheek blocks was set relative to the arms of the case of the piano. In the earlier days, the keyframe and keybed were then drilled for tuning pins used as locators. Then the back of the keybed was planed dead flat. The keyframe was roughly fit to this, (the forefinisher could only rough-set this because it was usually done without the keys or the stack) and then the dags were installed. The dags were located by gluing a piece of 1/8th inch veneer to the back of the keyframe (or the front of the dag, if the foreman was not looking), and then inserting the keyframe into the action bay and clamping it in place. The dags were then glued in place at intervals determined by the location of the veneer pieces. After the glue had set, the fit of the keyframe was checked again. (There is a lot of misunderstanding about the purpose of the dags. They are NOT there just for transportation. They serve the crucial function {in the NY pianos} of providing stability for the back rail of the action. Too tight, and the action will not shift reliably. Too loose, and the action flops around and the touch is not stable.) When this is done, the keybed is planed concavely front to back along the axis of the grain (or perpendicular to the keys, if you prefer). It is planed such that the depth of the convexity is app. 1/16 inch; and its deepest point is under the center rail of the keyframe. Then 1/8th to 1/4th inch of the leading side of the top of the keybed is planed convex by 1/32nd to 1/16th inch, with the high point at the center of the keybed. The leading 1/8th to 1/4th inch of the leading edge of the underside of the front rail is then planed to be a mirror image of the keybed; that is, convex in the opposite direction by 1/32nd to 1/16th inch. The keyframe is constructed so that only the end stretchers between the front and back rail are flat. These are then planed so that they do not touch the keybed, save at the narrow areas described above. The procedure for locating the cheek blocks has varied over the years. The most prevalent iteration being to use the location as set from the arms, and then locate the brass guides relative to the pins in the keyframe. Once that has been done, the keyframe can be inserted and clamped in place with the cheek blocks, and the forefinisher can work to perfect the mating of the keyframe and keybed with (hopefully) fine sandpaper. This whole thing is a part of the overall forefinishing process, which, in Steinway's case, is a patent process. (Basically, that means that not only can it not be copied, but they cannot vary from it and still legally use the descriptive language from the patent documents.) The purpose of this section of the forefinishing process is to provide the most solid connection of the action to the balance of the piano possible, so that the pianist may get the feedback of the vibrations of the piano through the keys. (This speaks directly to the recent threads on the forum, re: "singing rims" etc.) The original patent documents describe this feedback quite dramatically and make interesting reading anyway... This process was used from very early on, right up through the use of the Pratt-Read keys and keyframes, until 1985, when the switch was made to Renner action parts and Renner and Kluge keys and keyframes. Servicing keyframes from this period is usually a process of figuring out what was done during the original manufacture and why it was done. Most often, in my experience, this has involved some degree of seeing through the mist created by some well-meaning, but ill-advised colleague. Basically, even if some set of arbitrary numbers seem to be out of whack, if the original work seems to have been done a certain way, just follow that. There is usually some (good) reason that something was done, and most of the time, you just have to redo your own work when you find out why. These pre-1985 keyframes were made of heavy Oak, Walnut and Maple. They were well seasoned and held regulation well. The Renner/Kluge keyframes are made of European species, are much lighter and are designed for a different kind of piano altogether. Beginning in 1987-1988, NY began planing the keybeds mostly flat, with areas of concavity around the maple plugs for the glides. While some improvements have been made over the earlier keyframes, they are wildly susceptible to weather changes, as I am sure you have discovered. Further, their lightness of mass influences not only their ability to hold regulation, but also their ability to transmit energy. Their planing in the front rail area is usually limited to the last 4-6" of distance from the ends of the keyframe, and seems to be further limited to the keybed itself - there is little, if any, attempt to mirror the work. The result, of course, is a keyframe which is never quite stable; which brings me to: Hamburg keyframes. In the period immediately following W.W.II, the Hamburg pianos were, at first, just put together from whatever could be salvaged from London and Berlin, as well as Hamburg. There was also, for a time, some bigger pieces coming from NY. But it was a different world. The influence of Renner can hardly be overstated. Renner was, and is, the world's largest producer of piano parts. They make parts to manufacturer's specifications, to be sure; but, the manufacturers make sure their specifications fit what Renner is set up to do. No company was/is more in this predicament than Steinway. Has it been all bad? Definitely not, but it has significantly influenced the course of the company. So, what about Hamburg? What about it, indeed? Because things were in turmoil for a while, I will take an arbitrary date of 1960 for talking about Hamburg keyframes. Yes, it was mostly stable during the preceding 15 years, but there was variation. Anyway, the post W.W.II Hamburg piano became a truly European instrument. Nowhere is this more true than in the concept of the action, and its relation to the rest of the piano. In Hamburg, the keybeds are generally dead flat. None of the planing described for the NY pianos above. The action frames are what you see on the post-1985 NY instruments, lightly built and highly susceptible to weather changes. The installation is markedly different as well. All of the fitting is done to predetermined dimensions. Keyframe, cheek block, dag and action placement are done independently. At one point (I think it is no longer the case), the entire action was introduced as a finished unit quite late in the manufacturing process. The keyframe itself, while arched, is so light that it depends on the glides for structural support. These actions depend for their bedding on making things work. The keybed, being flat, does not lend itself to being replaned. The keyframe, in many of the ones I have seen, is only planed toward the ends, so that it is a relatively sharp angle. Smoothing this angle is sometimes all that is needed. END
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