Wonder why the the back posts became loose?? In a school, pianos get pushed around a lot. Perhaps some one pushed it backwards from the keyboard and it toppled over. If there was nothing in the news of a first grader getting smushed maybe they were lucky. This hazzard makes me uneasy (I have seen this almost happen) and is one more reason I encourage stage dollies on institutional pianos especially in choral and band rooms. When a piano falls over backwards a lot of things can happen. One is that the action standards get cracked. The other is that the plate can crack. Check for these things before repairing the separation. I agree that plate bolts should go all the way through, especially with all the loose plate screws I find on newer pianos here in the "heartland". A nice touch if replacing the lag screws with oval head carriage bolts is to counter sink the washers and nuts on the back side. That way walls and clothes don't get ripped up, and looks a lot more professional. I'd release the tension. It will take a couple of more tunings, but if you don't release tension and if the piano never does stableize, which is a risk in this repair, you will always wonder if it would have, had you released the tension. Usually on older uprights the separation is so drastic there is no question about releasing the tension. Also in releasing the tension you will know how the pin block is. There is no guarantee, its like an operation, the patient might not recover, but the doctor still gets paid. Does it have only two pedals? This piano is not under warranty? Is it insured? If so, and maybe since the repair can't be guaranteed it should be replaced?? A public school might need two bids, and might expect a "free" estimate. Richard Moody South Dakota ---------- > From: Warren Fisher <fish@communique.net> > To: pianotech@byu.edu > Subject: Upper back repair > Date: Thursday, March 06, 1997 7:27 PM > > I have a yamaha school studio in a public school that has the upper ends > of the back posts and its cross board pulled away from the pin block > about a quarter inch on the left tapering to a crack on the right. My > intent is to put glue in there, put about ten pipe clamps across the top > and then remove the top plate screws and drill all the way through to > the back to install large 6 large bolts to support this puppy. > > Do any of you have any thoughts, warnings, tips or reservations about > this process? > > I have a couple of questions: > > 1. If I just tighten this back up after gluing, how much pitch increase > will I get? The piano is just a little flat. Could it be too much? Do > I need to release string tension with all that can of worms? > > 2. Is there anything else I should check before I start gluing? > > Any help will be greatly appreciated? > > Warren > -- > Warren D. Fisher > fish@communique.net > Registered Piano Technician > Piano Technicians Guild > New Orleans Chapter 701
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