<!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 6.00.2800.1126" name=GENERATOR></HEAD> <BODY> <DIV>Hello gentlemen, </DIV> <DIV> </DIV> <DIV>Just this fast thought :</DIV> <DIV> </DIV> <DIV>is not there a third "magic line" between the pivot of the repetition = lever and the hammer center pin , where the roller/jack is more or less located at = letoff, may be because the jack would reengage better then (lesser =  friction path ) ?</DIV> <DIV>indeed not a leverage question anyway.</DIV> <DIV> </DIV> <DIV>Regards to all.</DIV> <DIV> </DIV> <DIV>Isaac OLEG Entretien et réparation de = pianos . PianoTech 17 rue de Choisy 94400 VITRY sur = SEINE FRANCE tel : 033 01 47 18 06 98 fax : 033 01 47 18 06 90 cell: 06 60 42 58 77 = </DIV> <BLOCKQUOTE style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #0000ff 2px = solid"> <DIV class=OutlookMessageHeader dir=ltr align=left>-----Message d'origine----- De : pianotech-bounces@ptg.org [mailto:pianotech-bounces@ptg.org]De la = part de Erwinspiano@aol.com Envoyé : samedi 18 = janvier 2003 21:45 À : = pianotech@ptg.org Objet : Re: Moving Action Lines of Center </DIV>In a message dated = 1/18/2003 7:09:18 AM Pacific Standard Time, mfarrel2@tampabay.rr.com = writes: <BLOCKQUOTE style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #0000ff 2px = solid; MARGIN-RIGHT: 0px" TYPE="CITE">Subj: Moving Action Lines of Center Date: = 1/18/2003 7:09:18 AM Pacific Standard Time From: <A = href="mailto:mfarrel2@tampabay.rr.com">mfarrel2@tampabay.rr.com</A> = Reply-to: <A href="mailto:pianotech@ptg.org">pianotech@ptg.org</A> To: <A = href="mailto:pianotech@ptg.org">pianotech@ptg.org</A> Sent = from the Internet     Terry </BLOCKQUOTE>         In my = limited experience of checking the "Magic line" at the knuckle I've noticed = that even on the best of actions the only time the knuckle gets close to the = line is at the very end of the key /action stoke.  (I think Ron Overs action = is the exception.) So maybe the parameter is , that the closer the knucle is = to the line the better. I  think the most advantage gained is at the = wippen heel/capstan contact point. When this convergence line is right the = action gets very  fluid. Or , as My colleague Bob Davis so succinctly = put it to me the other night is , that leverage is leverage.    = Meaning that primarily you can move two things to increase action efficiency , = reduce lead and increase hammer weight.  These two are the key balance = point relative to the capstan or the knuckle placement relative to the centerpin.  Other than that the lines of convergence are where = friction can seriously be tamed , there by reducing the  need to add lead = to overcome it. Of course for me all this moving balance points and = convergence lines around still has to land me within  .390 ish dip and a 1 = 3/4" to 1 7/8" blow distance with a 1.5mm let-off.    Somebody else = jump in here and tell me something I might be missing.       Dale = Erwin     <BLOCKQUOTE style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #0000ff 2px = solid; MARGIN-RIGHT: 0px" TYPE="CITE"> I'm having a = difficult time imagining how to change the position of the knuckle/rep lever = contact relative to the magic line. I can see quite easily how to = manipulate the wippen heel/capstan contact - taller or shorter heel, capstan up = and down, and/or move capstan forward or back. Lots of easy opportunity = to put that contact anywhere you want it. I have a 1947 Baldwin = action where the magic line passes through the knuckle just above its center with = the key at rest. At full key depression the rep lever is almost up to the = magic line. A tiny knuckle would do it, but I have never seen one = so small. I suppose you could move the wippen flange down (move rail?) = somehow. But that's pretty weird. Is there some easy thing I am overlooking? Terry Farrell </BLOCKQUOTE> </BLOCKQUOTE></BODY></HTML>=