<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> <HTML><HEAD> <META http-equiv=Content-Type content="text/html; charset=iso-8859-1"= > <META content="MSHTML 5.50.4134.600" name=GENERATOR></HEAD> <BODY style="MARGIN-TOP: 2px; FONT: 8pt MS Sans Serif; MARGIN-LEFT: = 2px"> <DIV>The spread on all Yamaha grands (so far, anyway) is 112.5mm.</DIV> <DIV> </DIV> <DIV>Mark Wisner Piano Service Yamaha Corporation <= A href="mailto:mwisner@yamaha.com">mwisner@yamaha.com</A> &gt= ;>> oleg-i@wanadoo.fr 05/15/02 11:58AM >>> Hello, Whould = you please telle us what is the correct spread distance on the G series = ? Any time I saw one (1970 piano) with extra heavy touch (and little keydeep),<BR= >the whippen rail had moved towards the front . I thought of the DW UW = figure of these pianos as to be around 52 g DW vs 28g UW env - is it correct = ?) Thanks. Isaac OLEG > -----Message d'origine----- > De : owner-pianotech@ptg.org [<A href="mailto:owner-pianotech@ptg.org]De">mailto:owner-pianotech@ptg.org]D= e</A> la part > de Baldwin Yamaha Piano Centre > Envoye : mercredi = 15 mai 2002 18:51 > A : pianotech@ptg.org > Objet : Re: Touchweight = Metrology Question > > > > Hi Terry, >          &= nbsp;       Back to the original heavy touch. Balance rail hole > fitting, has a = huge effect on feel. Yamaha tends to have tight > balance rail > = hole fitting. > Two suggestions before you start. 1. Polish all key pins = and coat with > protech. 2.Fit the balance rail holes to the pin. Down = in humid > swamp land, > there should be a big difference. > > Regards Roger > > > At 08:02 = AM 5/15/02 -0400, you wrote: > >Richard wrote: > > >= >"Basically what I do is to pick a SW curve based on the target = ratio I > >want,  install FW to fit the FW max table ...." >= > > >How do you relate/figure SW to SWR? I thought target = SW should > be based on > >piano tone, and then geometry and = FW and whatever adjusted to accomodate > >the desired SW? > = > > >Unfortunately, this piano appears to have new Yamaha hammers on it. But > >they are not tapered, or arced. Friction in the hammer-shan= k flanges is > >all over the place. Is it reasonable to try the water/alchohol thing to > >shrink-size the bushings before = repinning the whole shebang? I wish the > >hammers and knuckles were more = worn, then it would be easy to > recommend a > >new top half of = the action. > > > >By installing FW to "fit" the FW max = table, are you suggesting that FW > >should be at or near that maximum = value? If so, why? Doesn't > "maximum" in > >this case mean that "at = that value or below is fine"? Or not? Thanks. > > > >Terry Farrell > > > >----- Original Message ----- > = >From: "Richard Brekne" <richard.brekne@grieg.uib.no> > >To: <pianotech@ptg.org> > >Sent: Wednesday, May 15, 2002 = 3:11 AM > >Subject: Re: Touchweight Metrology Question > = > > > > > > Farrell wrote: > > > > > > = > I am taking my second stab at touchweight metrology analyses of an > = > action (my first was half-hearted and incomplete). Yamaha G5, 1963, >= > action in very good condition. Complaint: action heavy. It is > = indeed with > > DWs all over the 60 to 80 gram range (mostly around = 65 grams). > Some notes > > do have a lot of friction, but = many measured notes only have 10, 11, 12 > > grams friction, so = clearly there is a problem with either too > much weight > > = hanging out somewhere, or bad geometry. KR is 0.49, BWs are > mostly around &g= t; > 50 to 55 grams or so. I have not measured strike weights and = wippen > > radius weights yet. > > > > > > KR of 0.49 is = down there quite a bit... which means the > capstan is in a > > = good ways and you should be able to lift all kinds of weight, but need > = > lots of key dip to get things to work.  So if you are in addition &= gt; > experiencing medium heavy to heavy DW then you probably have = a > fun job on > > your hands. > > > > > > But = this is real sketchy just with KR and vague DW, BW and > Friction hints. &= gt; > > > > > I like to take a few (10-12) samples of all parameters to get an idea > > of where the action is, then plan = what I want to end up with a "least > > work possible" perspective. I = aggree with David that ending up around > > 5.75 SWR is a good generic = solution that seems to work well > with most actions. > = > > > > > Basically what I do is to pick a SW curve based on = the target ratio I > > want,  install FW to fit the FW max table = David includes with his kit, > > and adjust leverage as neccessary to = make a decent enough fit. > > > > > > Make sure the = action spread and friction issues are taken > care of ahead > > = of time. > > > > > > > Maybe too early yet to even = be asking questions. Just wondering if > > anyone that is familiar = with this process has any > recommendations. Thanks. > > = > > > > This proceedure makes for a decent generic solution, and gets you > > started along the Stannwood path. It gets you looking at = and using his > > formula in a few different ways, and you start = routines in his > practical > > methods. It doesnt allow for much = "design" work tho as you are pretty > > much stuck with a very narrow set = of SW and FW parameters. But > its a good > > and easy place = to start. > > > > > > In your case, if your KR is = indeed only 0.49,  I would guess > you might > > end up = moving the capstan line back a bit > > > > > > > Terry Farrell > > > > > > > > > > Grin.. = Ed will correct me if I am thinking backwards again. It gets > > = worse when I think upside down :) > > > > > > > = > > -- > > > Richard Brekne > > > RPT, N.P.T.F.<BR= >> > > Bergen, Norway > > > <A href="mailto:rbrekne@broadpark.no">mailto:rbrekne@broadpark.no</A> &gt= ; > > <A href="http://home.broadpark.no/~rbrekne/ricmain.html">http://home.broadpa= rk.no/~rbrekne/ricmain.html</A> > > > > > > > > > </DIV></BODY></H= TML>