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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoPlainText>I’m glad this was reposted on this list as I’ve tried to respond to the other list via email with no success. I use the following guidelines for measure action ratios. Different people use different methods, I find this one to be the most accurate and meaningful. <o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>This is the beginning of addressing the other question which appeared on that other list but which I was unable to respond to with some hoop jumping. This had to do with different ratios between sharps and naturals. The bigger question is what is the overall ratio of the system and the second question would be what are the hammer weights (or strike weights if you prefer) that will give an indication of whether the match between leverage and hammer weight was correct. The issue of different ratios for sharps and naturals is a non issue, in my opinion. I agree with Nick G. that concern about the magic line is overrated. <o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>Once the action ratio is known then with a combination of various other criteria, the hammer weight or strike weight can be optimized always (as it should with the action ratio) keeping in mind the implication for regulation specs. <o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>Sorry I don’t have a picture.<o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>Ea = is the actuating segment of the lever <o:p></o:p></p><p class=MsoPlainText>Ra = is the reacting segment of the lever <o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>-Key Ea is measured from front of key to center of balance pin at punchings measured along the bottom of the key. <o:p></o:p></p><p class=MsoPlainText>-Key Ra is measured from center of balance pin to perpendicular line which passes through center of capstan top measured along the bottom of the key. <o:p></o:p></p><p class=MsoPlainText>-Wippen Ea is measured from the wippen center pin to a line perpendicular to the contact point of the wippen heel/capstan contact point measure along a line between the wippen flange center pin and the jack center pin. <o:p></o:p></p><p class=MsoPlainText>-Wippen Ra is measured from the wippen center pin to the jack center pin. <o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>-Shank Ea is measured from the hammer flange center pin to the center of the knuckle core measured along the shank. <o:p></o:p></p><p class=MsoPlainText>-Shank Ra is measured from the hammer flange center pin to the center of the hammer molding measured along the shank.<o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>Calculate the ratio of each lever according to following example RA/EA. The action ratio will be a product of the ratio of the three levers. In this case .49 * 1.59* 7.47 = 5.79 <o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><table class=MsoNormalTable border=0 cellspacing=0 cellpadding=0 width=360 style='width:3.75in;margin-left:-.75pt;border-collapse:collapse'><tr style='height:12.0pt'><td width=72 nowrap valign=bottom style='width:.75in;padding:0in 5.4pt 0in 5.4pt;height:12.0pt'></td><td width=72 nowrap valign=bottom style='width:.75in;padding:0in 5.4pt 0in 5.4pt;height:12.0pt'><p class=MsoNormal align=center style='text-align:center'><span style='font-size:10.0pt;font-family:Courier'>Ea<o:p></o:p></span></p></td><td width=72 nowrap valign=bottom style='width:.75in;padding:0in 5.4pt 0in 5.4pt;height:12.0pt'><p class=MsoNormal align=center style='text-align:center'><span style='font-size:10.0pt;font-family:Courier'>Ra<o:p></o:p></span></p></td><td width=72 nowrap valign=bottom style='width:.75in;padding:0in 5.4pt 0in 5.4pt;height:12.0pt'></td><td width=72 nowrap valign=bottom style='width:.75in;border:none;border-bottom:solid windowtext 1.0pt;padding:0in 5.4pt 0in 5.4pt;height:12.0pt'><p class=MsoNormal align=right style='text-align:right'><span style='font-size:10.0pt;font-family:Courier'>Ratio<o:p></o:p></span></p></td></tr><tr style='height:12.0pt'><td width=72 nowrap valign=bottom style='width:.75in;padding:0in 5.4pt 0in 5.4pt;height:12.0pt'><p class=MsoNormal align=right style='text-align:right'><span style='font-size:10.0pt;font-family:Courier'>Key<o:p></o:p></span></p></td><td width=72 nowrap valign=bottom style='width:.75in;border:solid windowtext 1.0pt;background:#92D050;padding:0in 5.4pt 0in 5.4pt;height:12.0pt'><p class=MsoNormal align=right style='text-align:right'><span style='font-size:10.0pt;font-family:Courier'>262<o:p></o:p></span></p></td><td width=72 nowrap valign=bottom style='width:.75in;border:solid windowtext 1.0pt;border-left:none;background:#92D050;padding:0in 5.4pt 0in 5.4pt;height:12.0pt'><p class=MsoNormal align=right style='text-align:right'><span style='font-size:10.0pt;font-family:Courier'>128<o:p></o:p></span></p></td><td width=72 nowrap valign=bottom style='width:.75in;padding:0in 5.4pt 0in 5.4pt;height:12.0pt'></td><td width=72 nowrap valign=bottom style='width:.75in;border:solid windowtext 1.0pt;border-top:none;background:yellow;padding:0in 5.4pt 0in 5.4pt;height:12.0pt'><p class=MsoNormal align=right style='text-align:right'><span style='font-size:10.0pt;font-family:Courier'>0.49<o:p></o:p></span></p></td></tr><tr style='height:12.0pt'><td width=72 nowrap valign=bottom style='width:.75in;padding:0in 5.4pt 0in 5.4pt;height:12.0pt'><p class=MsoNormal align=right style='text-align:right'><span style='font-size:10.0pt;font-family:Courier'>Wippen<o:p></o:p></span></p></td><td width=72 nowrap valign=bottom style='width:.75in;border:solid windowtext 1.0pt;border-top:none;background:#92D050;padding:0in 5.4pt 0in 5.4pt;height:12.0pt'><p class=MsoNormal align=right style='text-align:right'><span style='font-size:10.0pt;font-family:Courier'>63<o:p></o:p></span></p></td><td width=72 nowrap valign=bottom style='width:.75in;border-top:none;border-left:none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;background:#92D050;padding:0in 5.4pt 0in 5.4pt;height:12.0pt'><p class=MsoNormal align=right style='text-align:right'><span style='font-size:10.0pt;font-family:Courier'>100<o:p></o:p></span></p></td><td width=72 nowrap valign=bottom style='width:.75in;padding:0in 5.4pt 0in 5.4pt;height:12.0pt'></td><td width=72 nowrap valign=bottom style='width:.75in;border:solid windowtext 1.0pt;border-top:none;background:yellow;padding:0in 5.4pt 0in 5.4pt;height:12.0pt'><p class=MsoNormal align=right style='text-align:right'><span style='font-size:10.0pt;font-family:Courier'>1.59<o:p></o:p></span></p></td></tr><tr style='height:12.0pt'><td width=72 nowrap valign=bottom style='width:.75in;padding:0in 5.4pt 0in 5.4pt;height:12.0pt'><p class=MsoNormal align=right style='text-align:right'><span style='font-size:10.0pt;font-family:Courier'>Shank<o:p></o:p></span></p></td><td width=72 nowrap valign=bottom style='width:.75in;border:solid windowtext 1.0pt;border-top:none;background:#92D050;padding:0in 5.4pt 0in 5.4pt;height:12.0pt'><p class=MsoNormal align=right style='text-align:right'><span style='font-size:10.0pt;font-family:Courier'>17<o:p></o:p></span></p></td><td width=72 nowrap valign=bottom style='width:.75in;border-top:none;border-left:none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;background:#92D050;padding:0in 5.4pt 0in 5.4pt;height:12.0pt'><p class=MsoNormal align=right style='text-align:right'><span style='font-size:10.0pt;font-family:Courier'>127<o:p></o:p></span></p></td><td width=72 nowrap valign=bottom style='width:.75in;padding:0in 5.4pt 0in 5.4pt;height:12.0pt'></td><td width=72 nowrap valign=bottom style='width:.75in;border:solid windowtext 1.0pt;border-top:none;background:yellow;padding:0in 5.4pt 0in 5.4pt;height:12.0pt'><p class=MsoNormal align=right style='text-align:right'><span style='font-size:10.0pt;font-family:Courier'>7.47<o:p></o:p></span></p></td></tr></table><p class=MsoPlainText> <o:p></o:p></p><table class=MsoNormalTable border=0 cellspacing=0 cellpadding=0 width=209 style='width:156.55pt;margin-left:-.75pt;border-collapse:collapse'><tr style='height:12.0pt'><td width=63 nowrap valign=bottom style='width:47.0pt;padding:0in 5.4pt 0in 5.4pt;height:12.0pt'></td><td width=74 nowrap valign=bottom style='width:55.55pt;padding:0in 5.4pt 0in 5.4pt;height:12.0pt'><p class=MsoNormal align=right style='text-align:right'><span style='font-size:10.0pt;font-family:Courier'>Action ratio:<o:p></o:p></span></p></td><td width=72 nowrap valign=bottom style='width:.75in;border:solid windowtext 1.0pt;background:yellow;padding:0in 5.4pt 0in 5.4pt;height:12.0pt'><p class=MsoNormal align=right style='text-align:right'><span style='font-size:10.0pt;font-family:Courier'>5.79<o:p></o:p></span></p></td></tr></table><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><p class=MsoPlainText>-----Original Message-----<br>From: pianotech-bounces@ptg.org [mailto:pianotech-bounces@ptg.org] On Behalf Of Brown, David<br>Sent: Wednesday, September 19, 2012 4:00 PM<br>To: pianotech@ptg.org<br>Subject: [pianotech] Action ration measuring<o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>All -<o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>Asked this question on the wrong list……….<o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>I have enjoyed very much the ratio discussions, especially the ongoing one as few weeks ago ( key in , key out etc) that Nick and several others contributed to. My question-<o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>What is a practical way to actually take those measurements, especially the key measurements? Many times I will put a long center pin in a wip flange, tie off some carpet thread and use that to look at the lines of compliance for key- wip- capstan, but how to measure key in- key out accurately and predictably? Calipers? Rulers? Also, I have seen a couple of ways to measure for key in - from balance point to the end of the keytop, from balance point to where the front pin enters the key. This relates some to what Fred was posting, but thought another topic would not muddy things up.<o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>Thanks for this interesting discussion<o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>David<o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>David C. Brown RPT<o:p></o:p></p><p class=MsoPlainText>Piano Technician<o:p></o:p></p><p class=MsoPlainText>Division of Music<o:p></o:p></p><p class=MsoPlainText>Meadows School of the Arts<o:p></o:p></p><p class=MsoPlainText>Southern Methodist University<o:p></o:p></p><p class=MsoPlainText>Dallas Texas 1-214-768-3976<o:p></o:p></p><p class=MsoPlainText><a href="mailto:dcbrown@smu.edu"><span style='color:windowtext;text-decoration:none'>dcbrown@smu.edu</span></a> [cid:244020A4-F74B-47C9-84DB-458AE37E6657]<o:p></o:p></p></div></body></html>