Richard, This sort of 3/4 plate is entirely different from the European ones you usually see. The plate stops before the tuning pins, there is no frame structure over or behind the tuning pins. In the more familiar later American and European type the plates start to crack at the struts were they meet the agraffe area. They start at the bottom and travel up. With this sort the pin block rotates, pivoting on the plate flange, The bottom of the flange looses contact. You usually can put an object about 1/16" in the gap. The stresses on the plate are forcing the struts to bow upward. They usually start to crack from the top to the bottom. They often fail somewhere between the nose bolt and were they end at the string rest. Sometimes the nose bolts are pulling out of the framework underneath or the framing starts to fail. To observe the rotation it is useful to place rectangular objects, a couple of books for example, on the pin block yoke and observe how much it is twisted in the middle. A five to Seven degree angle is typical especially on the smaller model. Since the front end of the plate is rotated down the string plane begins to lower. You can see this by looking at how close the strings in the tenor area get to the damper guide rail. I have seen ones that are as close as 3/16" and they will vibrate against the rail when a forceful blow is delivered. I have some photos of a pin block replacement I did on ones of these quite a few years a go. If any one is interest I will place the few photos I have in digital form on my web site. I have a more complete set of these I have shown at some of my classes. Richard Brekne wrote: > John Hartman wrote: > >> Kent, >> >> I see things here that are all too familiar. In photo two I see >> evidence of a plate crack that has been welded or finished over. Plate >> cracks are very common in these early Steinways. > > > Are you referring to the first strut in picture number two ? If so...why > would that crack right there... on the top half of the strut ? I'da > thought with the pinblock wanting to rotate in that direction, any > crack on strut would have to open from the bottom. > >> The tuning pins were >> originally straight up and down. The pinblock has rotated and that's >> why the action is trapped. > > > Wow... thats a whole lot of rotation. Can the block on these really > rotate that much ? Why doesnt the front top edge of the pinblock pull > away from the stretcher then ? Looks like a clean fit still. > >> I have seen this many times and the only way to get the action out is >> to use a small carvers gouge and make small grooves for each drop >> screw and flange screw. > > > Why not drop the keybed... or is it non removable on these ? > >> The rotation of the block may also be why the dampers are starting too >> soon. > > > Why ? I'm sure you have a good explanation but this is a head scratcher > for me right off the top :) > > Check to see how > >> close the wires are from the damper guide rail in the middle area. >> >> >> John Hartman RPT >> > Cheers > RicB > _______________________________________________ > pianotech list info: https://www.moypiano.com/resources/#archives > > -- John Hartman RPT John Hartman Pianos [link redacted at request of site owner - Jul 25, 2015] Rebuilding Steinway and Mason & Hamlin Grand Pianos Since 1979 Piano Technicians Journal Journal Illustrator/Contributing Editor [link redacted at request of site owner - Jul 25, 2015] John Hartman The Universal, How-to, Hands-on Illustrator [link redacted at request of site owner - Jul 25, 2015]
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