<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns="http://www.w3.org/TR/REC-html40">
<head>
<META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=us-ascii">
<meta name=Generator content="Microsoft Word 12 (filtered medium)">
<!--[if !mso]>
<style>
v\:* {behavior:url(#default#VML);}
o\:* {behavior:url(#default#VML);}
w\:* {behavior:url(#default#VML);}
.shape {behavior:url(#default#VML);}
</style>
<![endif]-->
<style>
<!--
/* Font Definitions */
@font-face
{font-family:"Cambria Math";
panose-1:2 4 5 3 5 4 6 3 2 4;}
@font-face
{font-family:Calibri;
panose-1:2 15 5 2 2 2 4 3 2 4;}
@font-face
{font-family:Tahoma;
panose-1:2 11 6 4 3 5 4 4 2 4;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0in;
margin-bottom:.0001pt;
font-size:12.0pt;
font-family:"Times New Roman","serif";}
a:link, span.MsoHyperlink
{mso-style-priority:99;
color:blue;
text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
{mso-style-priority:99;
color:purple;
text-decoration:underline;}
span.EmailStyle17
{mso-style-type:personal-reply;
font-family:"Times New Roman","serif";
color:#1F497D;}
.MsoChpDefault
{mso-style-type:export-only;
font-size:10.0pt;}
@page Section1
{size:8.5in 11.0in;
margin:1.0in 1.0in 1.0in 1.0in;}
div.Section1
{page:Section1;}
-->
</style>
<!--[if gte mso 9]><xml>
<o:shapedefaults v:ext="edit" spidmax="1026" />
</xml><![endif]--><!--[if gte mso 9]><xml>
<o:shapelayout v:ext="edit">
<o:idmap v:ext="edit" data="1" />
</o:shapelayout></xml><![endif]-->
</head>
<body bgcolor=white lang=EN-US link=blue vlink=purple>
<div class=Section1>
<p class=MsoNormal><span style='color:#1F497D'>Julia:<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'>Keep in mind that the weights
from some suppliers are not accurate. I bought the little gram weight set from
a major supplier and found them all to be heavy (fortunately). I simply
drilled holes in each weight to remove the excess and calibrated each one.
Some of the weights have a lot of holes! Of course to do this you’ll need a
good scale properly calibrated and capable of reading down to at least 0.1
gram.<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'>dp<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 M. Porritt, RPT<o:p></o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'><a href="dporritt@smu.edu"><span
style='color:blue'>dporritt@smu.edu</span></a><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>Fenton
Murray<br>
<b>Sent:</b> Sunday, February 17, 2008 7:49 PM<br>
<b>To:</b> Pianotech List<br>
<b>Subject:</b> Re: Measure friction weight was: Weighting upright keys
question<o:p></o:p></span></p>
</div>
</div>
<p class=MsoNormal><o:p> </o:p></p>
<div>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>Julia,<o:p></o:p></span></p>
</div>
<div>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>To
do this work you'll need a set of gram weights. They are for sale at most of
the supply houses. With these weights you can place an exact amount on the end
of the key, say 50 grams, with the damper pedal depressed (important), see if
the key will fall to the point of let off. We are only concerned with the
travel of the key from it at rest up position down to the point of let of. The
lowest amount that will cause the key to drop (with the damper pedal depressed)
is the down weight. Then depress the key to let off and place an amount on the
key, the most the key will lift up to it's at rest position is the upwieght,
maybe around 25 grams. A little taping on the key bed to get things to move is
OK. You need to try some of this before trying to figure it all out. Once
you've spent some time with it you'll find it opening doors to a higher level
of action work. There is lot's to understand. Read the Stanwood articles in the
PTJ, I think they were early '90s. Use the PTJ on CD.<o:p></o:p></span></p>
</div>
<div>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>Fenton<o:p></o:p></span></p>
</div>
<blockquote style='border:none;border-left:solid black 1.5pt;padding:0in 0in 0in 4.0pt;
margin-left:3.75pt;margin-top:5.0pt;margin-right:0in;margin-bottom:5.0pt'>
<div>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>-----
Original Message ----- <o:p></o:p></span></p>
</div>
<div>
<p class=MsoNormal style='background:#E4E4E4'><b><span style='font-size:10.0pt;
font-family:"Arial","sans-serif"'>From:</span></b><span style='font-size:10.0pt;
font-family:"Arial","sans-serif"'> <a href="mailto:KeyKat88@aol.com"
title="KeyKat88@aol.com">KeyKat88@aol.com</a> <o:p></o:p></span></p>
</div>
<div>
<p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>To:</span></b><span
style='font-size:10.0pt;font-family:"Arial","sans-serif"'> <a
href="mailto:pianotech@ptg.org" title="pianotech@ptg.org">pianotech@ptg.org</a>
<o:p></o:p></span></p>
</div>
<div>
<p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>Sent:</span></b><span
style='font-size:10.0pt;font-family:"Arial","sans-serif"'> Sunday, February 17,
2008 3:22 PM<o:p></o:p></span></p>
</div>
<div>
<p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>Subject:</span></b><span
style='font-size:10.0pt;font-family:"Arial","sans-serif"'> Re: Measure friction
weight was: Weighting upright keys question<o:p></o:p></span></p>
</div>
<div>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'><o:p> </o:p></span></p>
</div>
<div>
<div>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>Greetings,<o:p></o:p></span></p>
</div>
<div>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'> <o:p></o:p></span></p>
</div>
<div>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>
So how do I start making measurements to see what weight a key(s)
neeeds? How do I measure friction? I am guessing that I should
start by measauring the the foot-lbs (or
cm-grams?) inertia it takes to start the power stroke at the wippen
heel/foot. Then I have measured my fricion...right? Then I can do the uw/dw
calculations.<o:p></o:p></span></p>
</div>
<div>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'> <o:p></o:p></span></p>
</div>
<div>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>Julia
<o:p></o:p></span></p>
</div>
<div>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>Reading.
PA<o:p></o:p></span></p>
</div>
<div>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'> <o:p></o:p></span></p>
</div>
<div>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>In
a message dated 2/16/2008 11:27:46 PM Eastern Standard Time, fmurray@cruzio.com
writes:<o:p></o:p></span></p>
</div>
<blockquote style='border:none;border-left:solid blue 1.5pt;padding:0in 0in 0in 4.0pt;
margin-left:3.75pt;margin-top:5.0pt;margin-bottom:5.0pt'>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>Given
a certain friction in the piano we are going to want to set up something like
maybe a downweight (dw) of 50 and an upwight (uw) of 25. All numbers in grams.
This is assuming a friction of 12.5.<o:p></o:p></span></p>
</blockquote>
</div>
<p class=MsoNormal style='margin-bottom:12.0pt'><span style='font-size:10.0pt;
font-family:"Arial","sans-serif"'><br>
<br>
<o:p></o:p></span></p>
<div>
<div class=MsoNormal align=center style='margin-top:7.5pt;text-align:center'><span
style='font-size:10.0pt;font-family:"Arial","sans-serif";color:black'>
<hr size=2 width="100%" align=center>
</span></div>
<p class=MsoNormal style='margin-top:7.5pt'><span style='font-size:10.0pt;
font-family:"Arial","sans-serif";color:black'>Delicious ideas to please the
pickiest eaters. <a
href="http://living.aol.com/video/how-to-please-your-picky-eater/rachel-campos-duffy/2050827?NCID=aolcmp00300000002598"
target="_blank"
title="http://living.aol.com/video/how-to-please-your-picky-eater/rachel-campos-duffy/2050827?NCID=aolcmp00300000002598">Watch
the video on AOL Living.</a></span><span style='font-size:10.0pt;font-family:
"Arial","sans-serif"'><o:p></o:p></span></p>
</div>
</blockquote>
</div>
</body>
</html>