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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