I've finally surfaced, and would like to chime in on this topic. I am under the impression that there were a number of changes implemented in the Steinway NY actions around 1912. The most easily noted is the change from a jack stop felt in the balancier window to a regulating button and spoon for jack-to-knuckle alignment. It seems to me that at about the same time, the "verdigris problem" begins to crop up. I have seen numerous NY Steinway actions from before 1912 that did not have substantive action center problems. It is much more common between 1912 or so and the mid 1980's to want either to install all new parts, or do significant work on the old ones. I have come to portray the problem, to my clients, as one of "gumming up the works". Steinway has dipped or soaked the parts, to stabilize or lubricate or something--one can see it in the darkened wood. Some years it is flange only, some years it seems to include the shank. Some years seem to gum up more and/or more quickly than others. But the short is that most of the actions built between 1912 or so and 1962, when they went to Teflon, will get the "dreaded verdigris problem" within 40-50 years. (Teflon then has its own issues, as do the earliest of the Teflon II parts.) If only some of our other household items would last so long! I have found that I can usually, but not always, keep an action going more or less acceptably by repeated applications of ProTek CPL and McLube 1725L. But the problem comes back sooner or later; in fact, I usually promise the client that it will be back. I can actually fix the problem only when the owner finds it worth spending the $ to replace parts. I agree with Fred in that I've never been convinced that the functional problem was the green stuff: it's just the most obvious indicator of the condition. I have, however, seen rather pitted center pins coming out of some of the centers. Clearly corrosion is at least sometimes at work, as well as the gumming up of whatever the wet stuff is. So I am sorry that the piano has this problem, but 40-50 years is actually a pretty commendable service life for a mechanical device. Now, on the question that brought this all up--is a one-time exposure to high humidity significant in this problem--I'd have to go with the very unlikely vote. I think it is a long-term oxidation/corrosion/ chemical reaction kind of problem. Unfortunate, but if it made the parts work better for 30 years or more, well, I would endorse the process unless there were a better one available. Like, hopefully, the current Teflon II implementation... Just my 2 cents worth. Doug ********************************* Doug Wood Piano Technician School of Music University of Washington dew2 at uw.edu doug at dougwoodpiano.com (206) 935-5797 *********************************
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