Certainly key frames distort, we both know that, and it is more likely that a keyframe would undergo movement than a keybed on average. Likely both of us agree on that point, as we live with it everyday bedding frames as part of regulation. Please understand that I have not been trying to make the point that rocking the keybed on the lyre is the only cause of keybed distortion, and I thought I was clearly making that distinction. While our two instances may not meet YOUR criteria, I don't understand how this is simply a numbers game, where you have more instances where it causes no harm than I have that it does. It does not follow logically that because some or even most instances of piano moving on the lyre do not result in keybed distortion, that it then follows than all pianos moved on their lyres would suffer no such distortion. It only takes one exception for that to not be true. Ron, I have great respect for your knowledge of piano technology. I have seen that amply demonstrated on this forum, to my benefit and others. But each one of us still has to rely on our own eyes and knowledge base to draw conclusions about what we are seeing in a particular piano. That does not mean that we are right all the time, but we have to do it so that we can function in our jobs because the piano is in front of us and we have to figure out what is going on and fix it. Whether or not you believe that this particular keybed distorted, I still have to rely on my senses and have faith in my own native intelligence. Don't you? When I am wrong about what I think I am seeing, the piano tells me and I seek other solutions. In this instance, I believe that my appraisal was correct. If that is insufficient for you, fair enough. That's all I can do. It doesn't make me right, but I believe I was in a better position to make that determination than you because I actually saw the piano, and it was an instrument that I had longtime familiarity with. In the case of the particular piano, if you were to remove the action and run a straight edge over the keybed, what I saw was a obviously greater rise than had been there before in the middle. The first indicator that something was rotten in Denmark was how much the ends of the key frame at the front were floating. From that and the straight edge I made the determination that the keybed was the culprit. As for numbers, I cannot tell you because it has been too long, and I am working from my memory. And you are right that humidity does have an effect on the relationship, lord knows I see some pianos with keyframes that are well bedded in one season and not so in the next. Baldwin grands are particularly sensitive to these changes because the frame is not terribly substantial, and they moved like crazy from summer to winter. But in the case of the Steinway, we are talking about the difference of about a day between times I saw the piano. If you read my earlier post carefully, you would see that I queried the movers about setting the piano on the lyre after I discovered the changes, and they indicated to me that that had moved the piano in this fashion. So I presumed nothing about how the piano was moved, and certainly presumed less than you are presuming to know about my thought processes here. My best guess is that they jostled the piano heavily and essentially dropped the piano onto the floor on its lyre. I have seen other movers set a piano down heavily onto the lyre, and wince when seeing it. I do believe that if you set the piano down in such an unkind fashion, particularly a large, heavy piano, it can cause damage to the keybed. The instances you quote where you are gently lowering the piano onto a pad would be far less likely to create such problems if at all. I do like. From longtime experience having my movers do it this way, I have only evidence that the lyre and keybed are safe, and that's enough for me. Others can and do choose to move pianos differently. Out the door to spend a few hours with some friends. Happy Thanksgiving. Will -----Original Message----- From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On Behalf Of Ron Nossaman Sent: Thursday, November 26, 2009 3:39 PM To: pianotech at ptg.org Subject: Re: [pianotech] Lyre Damage William Truitt wrote: > Let me re-ask my question again, Ron. To what other possible causal agents > could you possibly attribute the upward distortion of the keybed that we so > often see? I certainly can't blame rocking it on the lyre in the pianos I've seen in this condition that haven't been moved in many years. I'd be more likely to blame humidity shifts. And is it an upward distortion of the key bed, or a distortion in the action that's to blame? And how have you determined either? > What would qualify as "reasonable evidence" of a direct causal relationship > between setting the piano down on the lyre and keybed warpage? Both Al and > I have given instances of observation soon enough after such a move that any > other cause is unlikely, and the lyre is the most obvious suspect. And David indicated, as have I, that a whole lot of pianos get moved using the lyre, that show no such problems. Two reported suspected instances against a whole lot more instances where no such problem occurs doesn't meet my criteria for reasonable evidence. >Neither > of us are trying to make the leap of saying that all instances of warped > keybeds are caused by setting the piano on the lyre, only that we have a > particular instance where doing so is the only reasonable suspect. Reasonable suspect? Again, did you determine the key bed was deformed, or did you assume it because the end action glides were floating? >As to > how many instances are caused by setting the piano on the lyre, you and I > share essentially the same incomplete knowledge, regardless of our position. > We rely on anecdotal information and hopefully good logic, because we don't > have much else to go on. Which is why I said there's no reasonable evidence saying that rocking on the lyre deforms key beds, making the end glide bolts float. The number of observances against it are far higher than the number in favor. I couldn't care less who's right here, but I am interested in *what's* right, and I still see no reasonable evidence of lyre moves damaging key beds. > David, I don't doubt that a great many pianos are moved by setting the piano > on the lyre, and no harm comes of it. Lots of movers do it that way with no > ill effects (at least most of the time). A Steinway is a substantially > built piano with a thick keybed. But there are plenty of Crappendorfer > pianos out there where the keybed is as insubstantial as the rest of the > piano, and as cheaply made. And less tolerant of insult than the better > made instruments. Like that Hamburg C you used as an example of damage incurred by, you presume, rocking it on the lyre, which you also presume? > As for the side stresses on the treble leg, fair enough. Perhaps one could > even say it is a question of choose your poison, but you have to choose one > because you have to move the piano. One way to lessen that stress is to > make sure that you spin the caster wheel on that leg so that the wheel is > facing outward and away from the rim. Otherwise, at a certain point in > lowering the piano down at the bass end, the wheel will spin on its own to > achieve that position, suddenly and with a little jolt, adding more stress > than needs to be there. I know all that. I wasn't looking for instructions, just making a comparative observation. > For me, it is not hard to draw the following conclusion: IF it is true that > some instances of keybed warpage exist due to setting the piano on the lyre, > whether caused by poor and rough technique, the insubstantiality of the > keybed, or both; AND IF it is true that simple, quick, easy, and safe > methods exist that remove the need to set the piano on the lyre when moving > and risk such damage, THEN wouldn't it be true that said methods would be a > better and safer choice for moving a piano? (Logic 101 - if A is true, and B > is true, it follows that C must be true) If you like. > If one were so inclined, it probably would not be too difficult to set up a > long straight edge with a dial guage or digital caliper to take measurements > of deflection, both temporary or permanent, on a number of pianos, just to > see how much the keybed actually changes when doing a move. If one was interested in learning something, one should be so inclined as to attempt to find out. I just now did that, on a NY D, with a straightedge and punchings. A dial indicator, which I have handy, would take longer to set up, and wouldn't tell me anything more than this did, just to more decimal points. Key bed is concave by 0.06" in the center. Jack up one side, and float the piano on the lyre with a scrap of 2x4. Key bed is now 0.04" concave. The full weight of the piano on the lyre deflected it 0.02", or thereabouts. Removing the block, it went back where it was, nearly as I could tell. The end glide bolts didn't knock when it was up on the lyre. Is this proof of anything? No, not really. But it's an indication to me, along with the many years of similar indication, that rocking on the lyre doesn't typically endanger the key bed. For most of the time I've been in this business, I've set pianos up and down without the lyre, concerned with breaking the lyre or at least loosening the glue joints. So I'm not questioning the point because I'm defending my own "questionable" practice. I'm questioning it because, other than the structural risk to the lyre, I don't think it's likely enough to screw up key beds or action regulation, to use that as an argument against the practice. Ron N
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