<HEAD> <META content="MSHTML 6.00.2900.2873" name=GENERATOR></HEAD> <BODY> <DIV>Julia-</DIV> <DIV> </DIV> <DIV>The purpose of the lost motion is to allow the jack to reset under the hammer butt on a very slow release of the key.  What you need for this will vary considerably from piano to piano.  </DIV> <DIV> </DIV> <DIV>For example, on a good quality new piano with a smooth topped plastic jack (such as Kawai or Yamaha) there may be no perceptible lost motion, but the jack will still reset.</DIV> <DIV> </DIV> <DIV>Another piano may need the tiniest perceptible lost motion made as even as possible. You might tug on the hammer rest rail to see if all the hammers move back the same tiny amount.</DIV> <DIV> </DIV> <DIV>On a console with worn key bushings, twisted keys, irregular level and dip....do what you can to make it better and move on.  Sometimes perceptible improvement is the best you can offer.</DIV> <DIV> </DIV> <DIV>Ed Sutton<BR><BR></DIV> <BLOCKQUOTE style="PADDING-LEFT: 5px; MARGIN-LEFT: 0px; BORDER-LEFT: #0000ff 2px solid">-----Original Message----- <BR>From: KeyKat88@aol.com <BR>Sent: May 4, 2006 5:17 PM <BR>To: pianotech@ptg.org <BR>Subject: Qwestion about lost motion tests <BR><BR><ZZZHTML><ZZZHEAD><ZZZMETA content="text/html; charset=US-ASCII" http-equiv="Content-Type" charset="US-ASCII"><ZZZMETA content="MSHTML 6.00.2800.1106" name="GENERATOR"></ZZZHEAD><ZZZBODY style="FONT-SIZE: 10pt; FONT-FAMILY: Arial; BACKGROUND-COLOR: #ffffff"> <DIV>Greetings,</DIV> <DIV> </DIV> <DIV>         There seems to be a gray area about lost motion for me. In an upright or console, when all the keys are resting or balanced on their own weight, and if I push alittle on the top of the key to test lost motion amount, the check and hammer simultaneously move by my doing this. It is indicative of NO lost motion. Right?  However, if I grab the key between my fore finger and thumb and move the key up and down then I see a sustantial amout (1/32" to 3/64") of motion. Then what?</DIV> <DIV> </DIV> <DIV>        Which test is the truer test? In school, they taught us to just lightly tap on the top of the key and if the check winks slightly without winking the hammer then <EM><U>that</U></EM> is the lost motion. However, working with used pianos, I have discovered that if I secure the key between my fingers and move it up and down this will show me lost motion, even though the 'top of the key tap' test shows me there is none. </DIV> <DIV> </DIV> <DIV>     It seems there is a conflict, and geeeesh(!) there can be differences in the amout when two (let's say, for the sake of making my point obvious) two white keys side by side are set the same for the 'top of the key tap' test and when I use the 'up and down' test they can really different amounts from one another. What gives?</DIV> <DIV> </DIV> <DIV>      </DIV> <DIV>Thanks in advance</DIV> <DIV>Julix Gottshall</DIV> <DIV>Reading, PA </DIV></ZZZBODY></ZZZHTML></BLOCKQUOTE></BODY>