<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns="http://www.w3.org/TR/REC-html40"><head><meta http-equiv=Content-Type content="text/html; charset=us-ascii"><meta name=Generator content="Microsoft Word 14 (filtered medium)"><style></style></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1>Close but not quite. The real problem was this:<o:p></o:p><o:p> </o:p>With this particular wippen design the repetition lever spring is pinned between the post and the jack slot. The adjustment screw is quite close to the end of the slot. And it is installed at an angle such that, when viewed with the action at rest, the screw leans toward the knuckle. With the original hammershanks and knuckles this would not have been a problem; indeed, the screw is easy to adjust, it works reliably and there is adequate clearance for everything. For some reason on this action about half of the spring adjustment springs were backed out so far that they no longer contacted the short end of the spring. I’ve no idea why; even with insanely heavy hammers the springs were so tight most of hammers had a pronounced bounce.<o:p></o:p><o:p> </o:p>In this the original hammershanks have been replaced with an unsuitable aftermarket substitute made by Pratt, Read. (In fairness this may have been the only thing available at the time, but still….) The original knuckle location was probably 16 mm from the action centers. The knuckles on these shanks are positioned approximately 17.5 mm from the action center. I say “approximately” because it varies from about 17 mm on some to just over 18 mm on others. As well, the “rosewood,” or core, is not always perpendicular; some lean several degrees toward the flange, some toward the hammer. <o:p></o:p><o:p> </o:p>The action would have worked—not well and not consistently, perhaps, but it would have worked—with a knuckle diameter of 10 mm. But these knuckles have a diameter of between 11 mm and just under 12 mm. <o:p></o:p><o:p> </o:p>So, what was happening was that on those notes where the knuckle leaned toward the hammer and the repetition lever spring adjustment screw was backed all the way out the screw rubbed against the knuckle. Over the years a groove has been worn into the back of knuckles on the notes where this has been happening. On a light blow the drag was not only noticeable but severe enough to make it impossible to play the piano with any consistency. On a hard blow there was enough force and flexing to power the mechanism through.<o:p></o:p><o:p> </o:p>The temporary solution—I had only limited time to prepare the piano for a performance—was to weaken the repetition lever spring by gently bending it and run the screws in so they cleared the knuckles. The permanent solution will be to install new hammershanks.<o:p></o:p><o:p> </o:p>ddf<o:p></o:p><o:p> </o:p>Delwin D Fandrich<o:p></o:p>Piano Design & Fabrication<o:p></o:p>6939 Foothill Court SW, Olympia, Washington 98512 USA<o:p></o:p>Phone  360.515.0119 — Cell  360.388.6525<o:p></o:p><a href="mailto:del@fandrichpiano.com">del@fandrichpiano.com </a>— <a href="mailto:ddfandrich@gmail.com">ddfandrich@gmail.com</a><o:p></o:p><o:p> </o:p>From: pianotech-bounces@ptg.org [mailto:pianotech-bounces@ptg.org] On Behalf Of Ed Foote Sent: Sunday, July 17, 2011 7:32 AM To: pianotech@ptg.org Subject: Re: [pianotech] Weekend puzzler<o:p></o:p><o:p> </o:p>Could this be a spring hanging up on the distal side of the knuckle?<o:p></o:p><div>Ed Foote RPT <a href="http://www.piano-tuners.org/edfoote/index.html">http://www.piano-tuners.org/edfoote/index.html</a><o:p></o:p></div><o:p> </o:p><div><div id="AOLMsgPart_1_7cde33e1-66ec-4ceb-a482-351ff6649d8e">  <o:p></o:p></div></div></div></body></html>