<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> <HTML><HEAD> <META http-equiv=Content-Type content="text/html; charset=US-ASCII"> <META content="MSHTML 6.00.2900.2963" name=GENERATOR></HEAD> <BODY id=role_body style="FONT-SIZE: 10pt; COLOR: #000000; FONT-FAMILY: Arial" bottomMargin=7 leftMargin=7 topMargin=7 rightMargin=7><FONT id=role_document face=Arial color=#000000 size=2> <DIV> <DIV>In a message dated 9/22/2006 11:49:01 A.M. Eastern Standard Time, ilvey@sbcglobal.net writes:</DIV> <BLOCKQUOTE style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: blue 2px solid"><FONT style="BACKGROUND-COLOR: transparent" face=Arial color=#000000 size=2>I have mentioned this before but would be the problem with adding some key leads to the lever instead of a spring? </FONT></BLOCKQUOTE></DIV> <DIV></DIV> <DIV>Hi, David, and Colleagues -</DIV> <DIV> </DIV> <DIV>The difference between spring and lead is 'mass'.  Add lead, you add mass and increase inertia.  This can actually slow down the movement of parts in some circumstances.  Consider that a part like a trapwork lever must accelerate four times in one cycle of action.  (Remember that deceleration is merely negative acceleratiion.)  Springs add negligible mass, and can provide more (or less) acceleration than the one 'g' provided by gravity working on the lead.</DIV> <DIV> </DIV> <DIV>Best regards, <DIV> </DIV> <DIV><FONT lang=0 face=Arial size=2 FAMILY="SANSSERIF" PTSIZE="10">   ~  Tom McNeil, RPT  ~<BR>Vermont Piano Restorations<BR><VERMONTPIANO.COM><BR><BR>346 Camp Street<BR>Barre, VT 05641<BR>(802) 476-7072</FONT></DIV></DIV></FONT></BODY></HTML>