Don, Thanks for your much-valued input. -- JF On Wed, Oct 8, 2008 at 7:14 PM, Don Mannino <donmannino at ca.rr.com> wrote: > John, > > 2 - 3 grams in the wippen centers is not out of line for a Yamaha. Their > bushings are usually pretty firm. But try one, repin it for slightly firmer > fit, and see if the play improves. Side to side motion from clearance with > the birds-eye is not a problem, but spongy give is nice to eliminate as much > as is reasonable. > > Keep in mind that the wippen center is one of the least important centers > in the action. > > The rep levers in Yamaha pianos are also usually set in the factory the way > you have observed. You might get better repetition and spring regulation if > you pin this for a tighter fit, but will the gain be worth the time? It > might . . . . or it might not. > > Don Mannino > > > ----- Original Message ----- > *From:* John Formsma <formsma at gmail.com> > *To:* Pianotech List <pianotech at ptg.org> > *Sent:* Tuesday, October 07, 2008 4:11 PM > *Subject:* action centers - correct friction? > > List, > > I am reconditioning (prior to regulation) the action of a 1976 Yamaha G3 > grand. The questions I have concern the whippen and balancier action centers > vis-a-vis Don Mannino's post below that I found in searching the archives. > > In the section of bass whippens I've disassembled so far, I've noticed most > of the whippen flanges are anywhere from 2-3 grams, measured at the screw > hole. The balancier measures about 1-2 grams, measured at the drop screw > pad. > > Regarding what Don wrote below, and I consider him expert in this, I should > repin the loose flanges. However, I wanted to ask the list before I jump > into this. Is there any reason not to repin these centers that I am just > unaware of? Does Yamaha perhaps have a different standard for their > balancier and whippen flange centers? There is also slight sideward play in > the whippen centers, so my initial thinking is they could use repinning. > > What say you? > > > Thanks in advance, > > -- > JF > > Written by Don Mannino, 8/11/2007 archived at > https://www.moypiano.com/ptg/pianotech.php/2007-August/209291.html > > Here are my usual guidelines, with notes. Gram measurement is made with a > spring gauge at the screw hole, except where noted. > > > hammer flange centers > > Depends on felt quality and firmness. My usual range would be 2 - 6 grams, > depending on humidity and bushing quality. 2g during dry conditions is OK > with good bushings, but will give poor tone with spongy bushings. If it's > raining and the bushings are not especially firm feeling, pinning at 6 grams > might be good. Evenness from note to note is most important in this center. > > whippen flange centers > > 4 - 6 grams > > balancier center > > 4 - 5 grams measured at the drop screw pad (with spring detached, of > course). This is a very tight feeling bushing when you are testing with > the center pin. > > Jack should be pinned so that it falls slowly of it's own weight when the > wippen is held with the jack tender pointing up. This give a correct amount > of friction to match the weight of the upper part of the jack, which helps > control unwanted jack bounces during fast play. > > Don Mannino > > > > -------------- next part -------------- An HTML attachment was scrubbed... URL: https://www.moypiano.com/ptg/pianotech.php/attachments/20081008/856b0532/attachment.html
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