On Feb 12, 2011, at 6:33 PM, David Love wrote: > I especially liked Fred's illustration of the every other hammer > traveling technique. That would be hammer squaring. Travel comes before this, done upside down if you want to follow the genuine "official" recommended procedure. <G> And precise travel is definitely a prerequisite for this to work (if the hammer is traveling a bit, you will be tilting the hammer to compensate). Just a comment on the squaring procedure: It certainly isn't my invention. I learned a variant first from a Yamaha C&A tech who came through town to prep the C&A Yamaha several years ago. He did individual hammers, moving from one end of the action to the other one by one, and centered them each at rest between its neighbors (crowns centered between crowns), then raised them and checked for being centered, shank area between the same crowns. I tried it and liked it though it was a bit counter-intuitive which way you needed to burn. Then if you burned much, you had to re-center the hammer between its neighbors to check the final result. Then I learned from Takitori Itake of Shigeru Kawai the notion of centering them when they were raised, dropping them back down to decide on burning direction if needed. That was a great improvement, much more intuitive and no need to re-center. I taught that method last summer in a class at Las Vegas, and afterward Ed Sutton told me I should do every other hammer in a mass production procedure. And that way is both more efficient and I get more reliable results, as I just do one thing at a time and can get into more of a groove; also can look back at a whole section and see anything that wasn't quite exact, before moving on. In any case, I vastly prefer this to the more commonly described method of raising each hammer and watching its sides compared to its neighbors, watching the gap change or not. That works to a degree, but is slower and with sloppier and less reliable results. BTW, the Sauter techs had their own different way of seeing it, and due to language difficulties I simply couldn't get it straight just exactly what they were looking at and looking for, at least on the angled hammers. They seemed to want about a 2 degree lean toward the angle of the bore (maybe I should put that as being in the direction the hammer seems to be leaning), and I wasn't clear exactly why. I can speculate that it might be to compensate for the fact that the hammer mass is not quite centered in front of the shank (this was on uprights, but applied to grands as well), and that the hammer mass will cause some flex/twist during the blow, so it will end up striking squarely. But my German wasn't good enough to ask the right question, or to understand the response either in all likelihood. I did my best to explain what I had been doing, and they sort of seemed to think it was okay, just not their way. Regards, Fred Sturm fssturm at unm.edu "Since everything is in our heads, we had better not lose them." Coco Chanel
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