<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> <HTML><HEAD> <META http-equiv=Content-Type content="text/html; = charset=iso-8859-1"> <META content="MSHTML 6.00.2600.0" name=GENERATOR> <STYLE></STYLE> </HEAD> <BODY style="FONT-FAMILY: Times New Roman" text=#000000 = bgColor=#ffffff> <DIV><FONT face=Arial size=2>Of course you are right.  Bad = adding on my part.  Changing the BW by 12 grams puts it on the edge for inertia = problems with what's given.  Two leads at C4 probably puts the FW around 25 depending on the position.  Adding 12 grams there could be a = problem.  More data would be helpful.</FONT></DIV> <DIV><FONT face=Arial size=2></FONT> </DIV> <DIV><FONT face=Arial size=2>David Love</FONT></DIV> <BLOCKQUOTE dir=ltr style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; = BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px"> <DIV style="FONT: 10pt arial">----- Original Message ----- </DIV> <DIV style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: = black"><B>From:</B> <A title=oleg-i@wanadoo.fr href="mailto:oleg-i@wanadoo.fr">Isaac = OLEG</A> </DIV> <DIV style="FONT: 10pt arial"><B>To:</B> <A = title=pianotech@ptg.org href="mailto:pianotech@ptg.org">Pianotech</A> </DIV> <DIV style="FONT: 10pt arial"><B>Sent:</B> September 30, 2002 4:17 = PM</DIV> <DIV style="FONT: 10pt arial"><B>Subject:</B> RE: Heavy action</DIV> <DIV><BR></DIV> <DIV><SPAN class=501141423-30092002><FONT size=2>David, = </FONT></SPAN></DIV> <DIV><SPAN class=501141423-30092002><FONT = size=2></FONT></SPAN> </DIV> <DIV><SPAN class=501141423-30092002><FONT size=2>I believe you = read a little too fast, it is 60 DW 45 UW that makes 52.5 g Balance weight and a = light 7.5 g friction.</FONT></SPAN></DIV> <DIV><SPAN class=501141423-30092002><FONT = size=2></FONT></SPAN> </DIV> <DIV><SPAN class=501141423-30092002><FONT size=2>Even then, if all = else is correct, adding lead may not cause problems I = believe.</FONT></SPAN></DIV> <DIV><SPAN class=501141423-30092002><FONT = size=2></FONT></SPAN> </DIV> <DIV><SPAN class=501141423-30092002><FONT size=2>The hammers may = be very heavy to obtain this figure (I understood that, finally = !)</FONT></SPAN></DIV> <DIV><SPAN class=501141423-30092002><FONT = size=2></FONT></SPAN> </DIV> <DIV><SPAN class=501141423-30092002><FONT = size=2>Regards.</FONT></SPAN></DIV> <DIV><SPAN class=501141423-30092002><FONT = size=2></FONT></SPAN> </DIV> <DIV><SPAN class=501141423-30092002><FONT = size=2>Isaac</FONT></SPAN></DIV> <BLOCKQUOTE dir=ltr style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #000000 2px = solid; MARGIN-RIGHT: 0px"> <DIV><FONT face=Arial size=2>It's pretty hard to address this = without a little more data.  Adding lead may not be a problem depending on the actual front weight.  The bass section will often = take 4 leads without an inertia problem, but it depends on where they = are.  Your C4 has a balance weight of 47.5 g.  To bring it down to 40 = you will need to add 7.5 grams to the front weight.  With only two = leads at this position it may not be a problem, but it depends on the overall = front weight.  Balance weight at 40 is a reasonable target for this action.  That puts the DW/UW at 47/33 with 7 grams of = friction.  I'd rather see the friction around 10 here so I would check the = hammer flange pinning.  With 10 grams of friction, the DW/UW will be 50/30.  If the hammer weight/strike weight at this point is representative of the overall curve and the front weight is not too = high, that will produce a nice feeling instrument.  Stanwood's system = provides a nice method for analysis of these points.  The fundamentals of this system are available from the journal archives = in a series of 3 articles written awhile back.  I highly recommend = you become familiar with them.  It is perfectly designed to answer questions such as you are posing.  </FONT></DIV> <DIV><FONT face=Arial size=2></FONT> </DIV> <DIV><FONT face=Arial size=2>David Love</FONT></DIV> <DIV><FONT face=Arial size=2></FONT> </DIV> <DIV><FONT face=Arial size=2></FONT> </DIV> <BLOCKQUOTE dir=ltr style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; = BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px"> <DIV style="FONT: 10pt arial">----- Original Message ----- = </DIV> <DIV style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: = black"><B>From:</B> <A title=dm.porritt@verizon.net = href="mailto:dm.porritt@verizon.net">David M. Porritt</A> </DIV> <DIV style="FONT: 10pt arial"><B>To:</B> <A = title=pianotech@ptg.org href="mailto:pianotech@ptg.org">pianotech@ptg.org</A> </DIV> <DIV style="FONT: 10pt arial"><B>Sent:</B> September 30, 2002 = 6:01 AM</DIV> <DIV style="FONT: 10pt arial"><B>Subject:</B> Heavy action</DIV> <DIV><BR></DIV> <DIV>I have a Baldwin SF-10 here on which I just = measured the action weight.  C4 is 60 grams down, 45 grams up!  = Friction -- obviously is good -- down weight bad.  I hate adding lots of = lead to the keys, but on this piano there are only 3 weights in the bass = section, 2 at C4, only 1 in the upper treble, and actually 2 in the _back_ = of C8.  It appears that they did straight pattern leading on = this one.  I can add 1 - 2 weights to each key and bring it down = to 44 at A0, 42 at C4 and 40 at B7 (I'd probably just take out a back = weight on C8).  </DIV> <DIV> </DIV> <DIV>There is a point of diminishing returns on some actions where = you can reduce downweight by adding leads but the additional = inertia makes it feel to the player as though it is as heavy as it was before.  Does anyone think I'd get into inertia problems = adding this amount of lead?  </DIV> <DIV> </DIV> <DIV>dave</DIV><PRE>_____________________________ David M. Porritt dporritt@mail.smu.edu Meadows School of the Arts Southern Methodist University Dallas, TX 75275 _____________________________</PRE></BLOCKQUOTE></BLOCKQUOTE></BLOCKQUOTE= ></BODY></HTML>