Thanks, Fred, for this reply. Your first paragraph states quite clearly what my intuition was telling me so far as the implications of DW and UP insofar as it being more of a relative weight issue (keys/hammers) and possibly small geometry changes that make old and new parts not quite compatible. I also recognized that rep springs are not in play prior to let-off, which is why I stated in my first post that I didn't think that was the source of the problem. I feel a "heaviness" in my hands/fingers when I touch the piano, and as a pianist I just know it's not right. The measurements of course bear this out. Having said that, I don't rule out friction, and as time permits over the next few days I will re-examine critical interfaces using the very helpful input others have offered here. I have also just located 2 NYI Steinway repetitions from the last set I put on an M, and am anxious to take them to the school and compare them with the older ones on the D, see what's up. Installing them side-by-side might yield some interesting comparisons, if everything else is equal. Thanks, everyone, for your input. I'll keep you apprised in the days ahead. I won't have a large block of time for this piano for at least a couple days now, so there's time to mull things over, try a thing or two, etc. -- Paul Milesi, RPT Staff Piano Technician Howard University Department of Music Washington, DC > From: Fred Sturm <fssturm at unm.edu> > Reply-To: <caut at ptg.org> > Date: Mon, 23 Aug 2010 21:22:19 -0600 > To: <caut at ptg.org> > Subject: Re: [CAUT] Down Weight Too High With New Hammers > > On Aug 23, 2010, at 2:53 PM, Paul Milesi, RPT wrote: > >> Just wondering if >> this touchweight issue is common when putting new hammers on a >> Steinway D >> from this period, and if there is a typical or common remedy or >> approach to >> solving the problem. > > > From what you have said, it appears to be a weight and geometry > issue. Those high upweights indicate reasonably low friction. Key > leading on the heavy side sounds typical and removes the option of > adding lead (though I wouldn't rule it out entirely - not having seen > what you have seen, anyway). Roger Jolly is probably right in saying > that cleaning and lubing the rep springs and grubs will make it feel a > little lighter, but I don't believe it will change downweight/upweight > (they aren't engaged during the part of key travel that is measured > for weight). The change in feel will occur at the end of the > keystroke, and can be very noticeable if there was caked grease and > crud in there. > I don't understand how the old geometry wipp can cause a difference > in weight/ratio compared to the new one, but experience seems to say > it can. After all, the capstans are touching the wipp heels at the > same point, and the jack/rep lever is contacting the knuckle at the > same point, whether it is new style or old. I guess it must have to do > with the angle at which the jack addresses the knuckle, as that > certainly does change (enough to require different thickness let off > buttons). It wouldn't seem that changing one factor - the knuckle > distance - would make that much difference, but it seems that it does. > The newer wipp has very subtle differences in things like jack > profile. This thread makes me curious to look very closely at just > what those differences actually are. > In any case, as a practical matter, the easiest thing to address > might be weight. Reduce each hammer 1 gram, and you are in a better > ballpark. Not a walk in the park, but doable (or close - 1 gram is > about the max you can comfortably remove from a hammer by re-arcing > and tapering). It does require removing and replacing all the hammers > and shanks (and re-aligning), and a bench disc sander at a minimum, > with Spurlock's tail arcing device or equivalent. Tapering can be done > fairly evenly by timing and feel (how long and hard you hold the > hammer against the sanding disc, balancing from one side of the hammer > to the other). A scale to weigh before and after. You will need to > taper into the felt area (not all the way to the crown) to get enough > weight reduction. > If it weren't a Steinway, I'd look at a quick geometry change using > split balance punchings. But it is a Steinway, so no soap. At least > not that I know of. Maybe Ed Sutton's idea about shimming the wipp > would work. Worth the experiment. > Regards, > Fred Sturm > University of New Mexico > fssturm at unm.edu > > > > > >
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