Terry, I have done this repair a few times. I usually let all the tension off on the strings, as I find it is quite hard to clamp the gap closed even then! Clamping does need to be done before inserting the bolts, as I find the bolts alone will not close the gap much on their own, but they do hold well after the adhesive has gone off. If you don't have a compressor that is portable, you may be able to get down sevral sizes on your "hoover" hose by taping consecutive down sizes of plastic hose..........just a suggestion. I have usually found pva wood glue to be up to the job. Bringing the piano back to pitch is not as bad as you may think, as the strings will have been in the piano for sometime, and therefore do not strectch like new ones. I am not the Buddah, but this might help Regards Tony Court (BSc hons NAMIR) ----- Original Message ----- From: Farrell <mfarrel2@tampabay.rr.com> To: <pianotech@ptg.org> Sent: Tuesday, July 25, 2000 5:44 PM Subject: Pinblock/Frame Separation > Hello List Friends. I ran into a pinblock separated from the frame on a 1967 > 45" Baldwin Hamilton studio upright today. I have done this repair > previously, but only with 1/8" or smaller cracks. This puppy is slightly > more than 1/2" separation in the hi treble, tapering down to just less than > 1/2" separation in the low bass. This strikes me as being a BIG separation. > I plan on replacing the eight 5/8" dia. wood screws along the top edge of > the plate with 6" long 5/8" dia. bolts that will run through the whole > plate/pinblock/frame assembly. I will also put West System epoxy thickened > with their gap-filling, hi-density filler between the two separated surfaces > before drawing the whole assembly together with the eight thru-bolts and > several pipe clamps. > > I have four questions: > > 1) The plate is bent forward quite a bit - especially in the hi treble. If > you draw a line from the pressure bar in the high treble, extending out > to the edge of the plate, this is where most of the bend occurrs (at the > base of the pinblock). Question: when I draw the pinblock/plate back to > its original position against the frame, do I risk cracking the > plate? > > 2) Today I let the tension down on the strings because of the BIG > separation. The piano was a full half-step flat upon my arrival. I let > it down to three half-steps flat in bass and tenor, and two full steps flat > in treble. Are there any guidelines for letting it down any more > or less prior to drawing the pinblock/plate back to the > frame? > > 3) There are broken chunks of wood (big splinters, etc.) debris lying > between the pinblock back and the frame front. The debris is from the > screw holes as the screw threads were pulled forward out of the frame as the > plate/pinblock moved forward. Some of the debris is at the base of the > pinblock, about 8 inches down from the top of the pinblock. I feel the > need to get this stuff out before repairing because it will tend to limit my > ability to draw the pinblock/plate to the frame. All I can think of is > coathanger technology. Anybody have any better ideas???? > > 4) How long does this entire repair take you to complete (three service > calls - one to diagnose and measure, etc., a second to do the repair > and leave clamps in place for epoxy to cure, and a third to remove clamps > and pitch raise)? > > Thanks for any and all constructive input! :-) (I like smiley and winky > and frowny faces!) > > Terry Farrell > Piano Tuning & Service > Tampa, Florida > mfarrel2@tampabay.rr.com > >
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