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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='color:#1F497D'>I think it was more that there was negative crown but once I saw there was no positive crown with the string test I didn’t pursue trying to determine if the crown was actually negative nor by how much. When I took pressure off the board by letting down the tension and saw an increase in bearing (soundboard rise) and a change in the distance between the bridge and the struts (which I didn’t include below), and then crawled under to check the crown it was still not positive. The board had risen but not enough to turn negative crown into positive crown. The board was flat to begin with. BTW this piano had been restrung at least once before. <o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>Also note that the bearing measurements in some sections were more negative after the board was loaded than they were positive to start out with. The bridge transmitting the load between ribs from higher settings in adjacent areas pushed those areas lower then otherwise they could be by themselves. Nothing earth shattering there, just an observation. But it is a reminder that both when you design the rib array or set bearing on an existing board you want try and insure that the load on the ribs distributed equally. You don’t one are a set of ribs doing more work than another.<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><div><p class=MsoNormal><span style='color:#1F497D'>David Love<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>www.davidlovepianos.com<o:p></o:p></span></p></div><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><div><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> pianotech-bounces@ptg.org [mailto:pianotech-bounces@ptg.org] <b>On Behalf Of </b>Gene Nelson<br><b>Sent:</b> Thursday, June 23, 2011 9:38 AM<br><b>To:</b> pianotech@ptg.org<br><b>Subject:</b> Re: [pianotech] Soundboard Analysis<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><span style='color:black'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:black'><o:p> </o:p></span></p><div><div class=MsoNormal align=center style='text-align:center'><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'><hr size=2 width="100%" align=center></span></div></div><p class=MsoNormal>Question to ponder: Why would it be that although there is a positive change in downbearing when the tension comes off there is no apparent change in measured crown? <span style='color:black'><o:p></o:p></span></p><p class=MsoNormal><span style='color:black'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:black'>*** Bridge rotation?<o:p></o:p></span></p><p class=MsoNormal><span style='color:black'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:black'>Gene</span><o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Rib# Crown DB w-ten/wo Rib L H W (mm)<o:p></o:p></p><div style='border:none;border-bottom:solid windowtext 1.0pt;padding:0in 0in 1.0pt 0in'><p class=MsoNormal>Or section w-ten/ wo-ten<o:p></o:p></p></div><p class=MsoNormal><o:p> </o:p></p><div style='border:none;border-bottom:solid windowtext 1.0pt;padding:0in 0in 1.0pt 0in'><p class=MsoNormal>1 2/2 .006/.015 600 17 28<o:p></o:p></p></div><p class=MsoNormal><o:p> </o:p></p><div style='border:none;border-bottom:solid windowtext 1.0pt;padding:0in 0in 1.0pt 0in'><p class=MsoNormal>2 2/2 .006/.015 790 20 27<o:p></o:p></p></div><p class=MsoNormal><o:p> </o:p></p><div style='border:none;border-bottom:solid windowtext 1.0pt;padding:0in 0in 1.0pt 0in'><p class=MsoNormal>3 2/2 .009/.012 940 20 27<o:p></o:p></p></div><p class=MsoNormal><o:p> </o:p></p><div style='border:none;border-bottom:solid windowtext 1.0pt;padding:0in 0in 1.0pt 0in'><p class=MsoNormal>4 1.5/2.5 -.006/.003 1040 20 27<o:p></o:p></p></div><p class=MsoNormal><o:p> </o:p></p><div style='border:none;border-bottom:solid windowtext 1.0pt;padding:0in 0in 1.0pt 0in'><p class=MsoNormal>5 0/.5 -.003/.003 1080 22 27<o:p></o:p></p></div><p class=MsoNormal><o:p> </o:p></p><div style='border:none;border-bottom:solid windowtext 1.0pt;padding:0in 0in 1.0pt 0in'><p class=MsoNormal>6 0/0 -.009/.006 1120 21 27<o:p></o:p></p></div><p class=MsoNormal><o:p> </o:p></p><div style='border:none;border-bottom:solid windowtext 1.0pt;padding:0in 0in 1.0pt 0in'><p class=MsoNormal>7 0/0 .006/.018 940 21 26<o:p></o:p></p></div><p class=MsoNormal><o:p> </o:p></p><div style='border:none;border-bottom:solid windowtext 1.0pt;padding:0in 0in 1.0pt 0in'><p class=MsoNormal>8 0/0 .006/.021 660 20 25<o:p></o:p></p></div><p class=MsoNormal> <o:p></o:p></p><div style='border:none;border-bottom:solid windowtext 1.0pt;padding:0in 0in 1.0pt 0in'><p class=MsoNormal>9 0/0 .006/.027 560 20 18 <o:p></o:p></p></div><p class=MsoNormal><o:p> </o:p></p><div style='border:none;border-bottom:solid windowtext 1.0pt;padding:0in 0in 1.0pt 0in'><p class=MsoNormal>10 0/0 .018/.042 390 18 23<o:p></o:p></p></div><p class=MsoNormal><o:p> </o:p></p><div style='border:none;border-bottom:solid windowtext 1.0pt;padding:0in 0in 1.0pt 0in'><p class=MsoNormal>11 0/0 .022/.045 340 17 23<o:p></o:p></p></div><p class=MsoNormal><o:p> </o:p></p><div style='border:none;border-bottom:solid windowtext 1.0pt;padding:0in 0in 1.0pt 0in'><p class=MsoNormal>12 0/0 .025/.050 270 16 23<o:p></o:p></p></div><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>David Love<o:p></o:p></p><p class=MsoPlainText>www.davidlovepianos.com<o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText><o:p> </o:p></p></div></body></html>