Dave, et al, I was wondering who would speak up on this. Seeing that no one else has, and there seems to be some continuing interest, here are some thoughts: - What you are seeing is not all that uncommon. It is primarily, but certainly not exclusively, found on larger instruments. S&S Ds and Bs in particular are susceptible. While there are ways in which the problems you describe can sometimes be ameliorated temporarily, the correct fix is, of course, a new board. - This goes largely, but not exclusively co-equally to the much-debated method of construction used, changes made in those methods over time (beginning in the mid-1950s, and pretty much completed during the later 1980s/early 1990s), and, like it or not, the combined problems faced by all piano makers of decreasing quality both as to raw materials and labor pool. - The letter you received from the person at S&S is a paraphrase of what various folks in various positions there have been saying for at least the last 40 years about this and similar issues. I have copies of similar correspondence and/or notes from conversations relating to service dating back to the mid-1960s buried someplace about this kind of thing. - Do not count on S&S to fully acknowledge the problem. Even if they do, you cannot be sure of how the repairs (if in fact, any are authorized at all) will be carried out. In the event that they do, I would urge you to take exceptionally careful measurements of everything from deck height (of both the plate and the under side of the pin block) to speaking length; and then make sure to document everything with appallingly anal clarity. - FWIW, it may well be that you simply wind up having to live with the beast. If that turns out to be the case, encourage the owners to start planning now on having the board (and, in all likelihood, the block) replaced sooner rather than later. And, have that work done elsewhere. Best regards. Horace At 05:07 PM 7/4/2005, you wrote: >Esteemed list > > I have taken my time following this up as I ponder >what attitude to take. For new readers...to review.... >bridge is lower on speaking side then backscale side >by as much as 20 thou. over much of this new D >Steinway.. including the bass bridge. The result is >strings that will not stay seated, and various buzzing >off the backscale. It is severe enough in at least one >place the back of the bridge is highenough that there >is no pressure on the backscale plate before the hitch >pin and the string will buzz on the plate unless held >down to the plate or muted. > > From previous posts I understand bridges do >not roll so much as soundboards in front of the >bridges may collapse. Also it was suggested by at >least one person that the piano was built this way. > > I have a response from Stienway, and have >respectfuly taken off the name of the person >writing for the moment. They are coming from NY >to see this piano and in light of the response >I hope for more feedback. They obviously wish to >manage the problem and leave it alone. I can not >see strings staying seated in its current condition. >String seating and hammer mating is at present, in >my opinion, a waste of time. > > Here it is......... > >------------------------------------------------- >Hello David, > >First, thank you for your very complete letter. Your >comments are very helpful in trying to assess any >possible problems with this piano. > >As to the excess glue, you are correct that this is >simply glue squeeze-out that should have been cleaned >up in the manufacturing of the piano. >It is sometimes difficult to see this at the belly >rail but, as you have done, should be removed to >prevent possible buzzes in the future. > >Concerning the bridge/downbearing, let's keep an eye >on this if the buzzes have been eliminated for the >time being. While it presents a situation to >keep an eye on, I do not want to make an immediate >pronouncement that there is something wrong there. The >primary thing that manufacturers look for is >the total composite bearing on the front and back >combined. This should, of course, be a positive >bearing. Theoretically, there should be positive front >and back bearing. However, pianos seldom conform to >the theoretically correct. I have taken many bearing >measurements - on both good sounding and >not-so-good sounding pianos. Some of the best sounding >pianos have exhibited the measurements you describe >below while some of the lesser sounding pianos >are textbook perfect. The downward forces of the >strings over the bridges (anywhere from 800 - 1100 lbs >of force) cause each piano to develop its own >unique shape. Sometimes that "settling" can be >measured to exhibit what we technicians commonly cause >bridge roll. That in itself is not a great cause >for concern but rather a sign that we need to monitor >this in case tonal issues arise consistently with a >piano. > >In my experience, seating and leveling the strings, >hammer filing, voicing meticulously, hammer spacing, >and making sure the bridge pins are seated in >the bridges alleviate any tonal problems 98% of the >time. You MAY have one of the "2% pianos" there but >let's wait and see if problems develop again >before we determine a course of action. > >Again, thanks for your very detailed and thoughtful >note. And please call or contact me if I can be of >service on any issues or questions you have. > >---------------------------------------------------- >Some of my Original Letter to Stienway........ >------------------------------------------------- >Hello > > Dave Renaud here, Ottawa-Gatineau, Canada. > > One of my clients is the Quebec Conservatory in >Gatineau Quebec. > > They have a new D you are likely aware of. It >was in ......cut............... > > I have a few observations that should be >investigated. > >Minor...... There were very large 2-3 inch long >shards of glue where the soundboard meets the belly >rail. Some of these thin shards from oozing glue >(I saved some, could take a pic.), were lightly >touching/buzzing against the board. I cleaned this up, > It eliminated some buzzes and did take time to >troubleshoot.........when all else was eliminated, I >thought it had to be the glue joint along the rim. > >Major...... The bearing on the back of the bridges >is high, the bearing on the front(speaking side) >much lower. As much as 20 at the back and 0 at the >front. This is all over, on both the treble , and bass >bridge. I was motivated to measure because a buzz on >the backscale could not be eliminated without pushing >the string down on the backsacle plate. This string >would not seat on the plate due 0 bearing over the >plate, This lead be to wonder if Perhaps the back of >the bridge was high. It is, and the front is >low, string travelling downhill to the speaking >length. > >These measurements were made with a Lowell gauge. > >I followed up by having xxxx from xxx measure with a >bubble gauge. He had negative measuments on the bridge >cap angle all over the piano as much as negative 18 in >places. I then had xxxxx look at it and confirm the >same thing. > > The strings should travel "uphill" to its >termination point at the speaking length. >They are travelling downhill to the speaking length. > > Marcel came down from Quebec city, and spent a day >seating and mating strings, did a wonderful job, and >the piano was much better. > > With the negative slop to the bridge nothing will >stay seated for long. > > What believe has happened with this piano is >technicians arriving for a day, with a program >in mind to treat normal problems. Indeed, they find >strings that need seating, and hammers that need >mating....normal.....and proceed to fix it. > > But on this piano, the poor seating, and string >mating is NOT because it was neglected, or not >maintained properly, and not because needs proper >concert service. We can do that. It is a recurring >symptom of the negative bridge cap angle. > > The opinion that I am hearing suggested from techs >is the soundboard at the front of the bridge may have >collapsed somewhat. Hmmm...that belly rail that >should supports the crown and all those oozing glue >shards at that very joint. Could this mean something >related. What does those shards suggest in the >manufacturing process. Just too much glue? not >securely glued down at the belly normally? Just not >cleaned up? Just thinking out loud ...any thoughts >here. > If I am missing something here I am very >interested in understanding how this can be. >Your thoughts, observations, and suggested solutions >will be of great interest to me. > At this point I believe I have observe and >diagnosed >something everyone else has missed. Not that others >were in any way delinquent, they did fine fine >work, but were I think on a schedule, a program to >follow, and seeing the symptoms went straight to work >without sufficient "why is this." I happen to spent a >great deal of time in front of this instrument >tuning and pondering over recurring buzzes that >motivated me to look to the bridges,and check those >glue joints. > > I hope this has been helpful > > If I could make further measument charts, but I >think you see what is here. > If I can be of help, please ask away. > > > David Renaud > > > > > >__________________________________________________ >Do You Yahoo!? >Tired of spam? Yahoo! Mail has the best spam protection around >http://mail.yahoo.com >_______________________________________________ >pianotech list info: https://www.moypiano.com/resources/#archives
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