<HTML><HEAD> <META http-equiv=Content-Type content="text/html; charset=windows-1252"></HEAD> <BODY style="BORDER-TOP-STYLE: none; BORDER-RIGHT-STYLE: none; BORDER-LEFT-STYLE: none; BORDER-BOTTOM-STYLE: none"> <P>Is the fore and aft angle of your new hammers a little off, maybe?</P> <P>Alan Barnard<BR>Salem, MO<BR>Joshua 24:15<BR><BR><BR><BR></P> <DIV style="PADDING-RIGHT: 5px; PADDING-LEFT: 5px; PADDING-BOTTOM: 5px; BORDER-LEFT: #000000 3px solid; PADDING-TOP: 5px"> <HR> Original message<BR>From: "Mark Potter" <BASES-LOADED76@SBCGLOBAL.NET><BR>To: "Pianotech List" <PIANOTECH@PTG.ORG><BR>Received: 09/25/2006 11:08:06 AM<BR>Subject: action reg puzzler on M & H BB<BR><BR> <DIV align=left>List -</DIV> <DIV> </DIV> <DIV>I am having a puzzling problem with a M & H BB grand action that I have never encountered.  Complete regulation (w/new shanks& hammers), everything works great with the exception of 3 notes - F6, A#6, G7 -  in the high treble.  I cannot get this to happen on the bench, and even in the piano when the notes are played softly, even in a trill, they perform perfectly.  However, under continuous mf - ff blows, as in tuning, after anywhere from 1 to 10 strikes (letting the key all the way up), the hammer will get caught on it's way back up by the back check, thereby not allowing it to strike.</DIV> <DIV> </DIV> <DIV>I have tried numerous adjustments to the angle of the back check as well as to the height of check for these 3 notes, to no avail.  Everything seems to be identical to the surrounding notes, including jack reg - both in the window and to the knuckle core -, rep spring strength, key dip, stroke, the arc of the tails, let-off, drop, etc., etc... you name it.  Keys are rebushed and moving freely.</DIV> <DIV> </DIV> <DIV>If anyone can shed some light on this puzzler I would be most grateful!!</DIV> <DIV> </DIV> <DIV>Mark Potter  </DIV></DIV></BODY></HTML>