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<DIV><FONT face=Arial>Lots of good methods for calculating the radius =
of an arc
have been provided. But there is also the question of whether the curve =
is a
true arc or some other shape (this assumes you have a specific shape as =
a
target). Most of the provided methods do not address that concern - in =
fact you
could have an obtuse angle with two straight sides rather than an arc. =
That's
why I suggested making a number of measurements along the curve - =
offsets from a
straight line.</FONT></DIV>
<DIV><FONT face=Arial></FONT> </DIV>
<DIV><FONT face=Arial>Terry Farrell</FONT></DIV>
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style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; =
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<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: =
black"><B>From:</B>
<A title=absolutepiano@comcast.net
href="mailto:absolutepiano@comcast.net">Absolute Piano</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> Wednesday, December 10, =
2003 4:40
PM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> Rib dimensions</DIV>
<DIV><BR></DIV>
<DIV><FONT face=Arial size=2><FONT face="Times New Roman"
size=3>Hello,<BR><BR>I'm trying to apply some science to my =
soundboard rib
making and I am<BR>looking for "tables of static values for the
Resisting Moment (W) and the<BR>Moment of Inertia (I) for all the =
possible
cross sections of sugarpine and<BR>spruce (DIN 1052 Class I will
suffice).<BR><BR>What is the formula for converting pounds/inch =
squared to
kg/cm squared?<BR><BR>Given a right angle connected to the outside of =
an arc
of a circle, how do<BR>you prove the circle is 60'? (I made a jig for =
crowning
ribs that is<BR>adjustable and I want to calibrate
it.<BR><BR>Thanks,<BR><BR>Jude Reveley,
RPT</FONT><BR></FONT></DIV></BLOCKQUOTE></BODY></HTML>