Jack, Thank-you so much. You got me onto my back and the problem became very clear. The lifter contacts the wippen too close to the pivot point of the wippen/flange, losing much of its leverage; accounting for (at least to my initial summation) the bizarre DW and UW. This design has a certain elegant logic to them. For the most part the rocker arms create a key which has a balance point corresponding to the balance hole of the key. So if that was an objective of the design, they certainly succeeded. I think, though, the design contains an excessive amount of inertia with all of that weight hanging off the end. Now to the solution. You said "bend the studs". They appear to be large round head screws and I am not sure if bending them is feasible without breaking wooden blocks they are screwed into. We will pull the action and dismantle the bottom support apparatus and experiment around a bit to find the most feasible location. Another possible solution maybe to build the bottom of the wippens up some, this will allow the rocker arms to be regulated back some, which will also change the contact point. There also is a lot of slide to the contact, I can't think of any solution to this problem yet. I appreciate the help you and Floyd provided. With the sales of new pianos falling through the floor for the past several years, I think it is becoming ever more important to save these older pianos and that may mean fixing design flaws. Andrew On Tue, Jun 8, 2010 at 9:31 PM, <JWyatt1492 at aol.com> wrote: > > Hello Andrew, > > If the action is mounted on medal studs about one to two inches > high then changes to the down weight is easy. You can bend the studs > backward ( toward the soundboard ) about 1/16th of an inch. This > can make an enormous difference. This changes the leverage of the > whip. > > Another thing you can do is polish ( buff ) the back of the " bi-level " > arm and lubricate the whippen heel felt. > > The piano action is simply a connected assembly of levers. There is > no magic or mystery to it. I have worked on these pianos many times > over the years, they are a little different but that's about all. > > Never adjust the actions studs in this manner on imported pianos. > > Regards, > Jack Wyatt > Dallas Chapter > > -- > Andrew Remillard > ANRPiano.com > 2211 Curtiss St. > Downers Grove, IL 60515 > 630-852-5058 > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://ptg.org/pipermail/pianotech.php/attachments/20100610/d1b42780/attachment.htm>
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