I think there is a very small window between too much pressure and not enough. I agree the damper wire/bushing should always be lubricated, and it seems to me this should be standard practice. I'm not sure it needs to be pre-dipping the wires. It's very easy to run a brush with ProLube along all the wires above the guiderail, damper pedal depressed. A few seconds does the job. I think the moderate "pressure bend" model is a good one, and it isn't just cosmetic. When the damper wires are adjusted so they travel in the middle of the bushings, with no contact (except by virtue of the bushing felt surfaces matching the wire surfaces precisely, or the fibers pressing inward evenly from all sides), there will be chatter (unless the bushings are so tight around the wire that they will cause sluggishness). At the bottom of the keystroke, the damper head will be vibrating back and forth. A couple of Stephen Birkett's videos show this in vivid detail (posted on his web site). That chatter can often be felt in the key, especially in the bass. And when the dampers return to contact the strings, the head is in motion. It will take much longer for the damper head, and the strings, to come to rest in this situation (also vividly demonstrated in BIrkett's videos). If there is side pressure, and it doesn't need to be much, the initial chatter doesn't occur (or it is much less), and when the damper contacts the strings, it is more of a solid, stable surface for the strings to damp against. I wish there was a Birkett video showing that scenario, but there isn't. In any case, experience shows that damping happens more rapidly when there is a bit of side pressure. (With the caveat that the upper bends have to be correct to space the head to the string, and to align it level to the string plane). Regards, Fred Sturm University of New Mexico fssturm at unm.edu On Jun 13, 2009, at 12:58 PM, Sloane, Benjamin (sloaneba) wrote: > Hello Ed, > I appreciate the feedback. Maybe I need to clarify in response to > your observation that > > "The wires do not need to be lubed to operate properly, at least, > not the > ones I have serviced for over 30 years in a school setting..." > > There are more reasons for lubing the wires than proper operation > of the damper. Before I get to that, I should add that depressing > the sustain pedal while lubing them in the piano in order to get the > solvent on the wire at the bushing point helps. The problem with > reducing the pressure bend is as I had described in the post you > quoted, that the dampers begin rattling when the gap is there in my > experience. I prefer to use a lubricant than reducing the pressure > bend to prevent this, something that is avoided by not leaving the > gap in the rebuilding process. > > Accuracy is obtained more easily in the damper regulation process > when lubing the entire damper wire, and tightening the damper lever > screws, snug, not tight. Twisting the damper is possible with or > without removal of the action when approaching it this way without > loosening the damper lever screw, and one also avoids putting a > notch in the damper wire by not over-tightening the damper lever > screw, which makes modifying the damper level as the felt wears > easier, preventing the screw from forcing the damper wire back to > the original place when attempting to raise or lower the damper > placement in the lever. In other words over-tightening can leave a > notch in the damper wire, or a scratch, if an effort is made to > twist the damper while it is tight, or not properly lubricated. As > for slipping of the damper wire in the damper lever by using this > method, this rarely occurs, and in the University setting, if it > does, you are there to fix it quick as pressure bend problems. It is > also consistent with the Steinway approach of reducing friction at > action centers to do this, though the location where the damper wire > and the damper guide rail felt meet is not usually described as an > action center, without causing the kind of problems people complain > about where Steinway action centers proper are concerned. I used to > get chewed out for over-tightening the damper screws in the shop I > started working in for this very reason. > > More than one way to skin a cat... > > Thanks for responding, > - Ben > > > > > -----Original Message----- > From: caut-bounces at ptg.org [mailto:caut-bounces at ptg.org] On Behalf > Of A440A at aol.com > Sent: Friday, June 12, 2009 8:40 PM > To: caut at ptg.org > Subject: [CAUT] Dampers, (was harpsichord etc) > > Ben Sloane writes: > << It is also possible that Steinway is not pre-lubing the damper > wires, > which we always did before installation, and as a result, even > though we did > not leave a gap, ours rarely failed to return to rest position, > while quite a > few of the new Steinways at CCM are having this problem even with > the gap. > I do not understand why Steinway won’t pre-dip the uninstalled > damper wires > into some kind of lubricating solution, which would be very simple > at that > stage, or if they are, why the solution is not working. >> > > Greetings, > The wires do not need to be lubed to operate properly, at least, > not the > ones I have serviced for over 30 years in a school setting. It > doesn't > hurt, but it is not necessary. What the wires need is to be > properly traveled > with just the slightest contact on one side of the bushing. New > Steinways > often exhibit damper sluggishness, but it is because of the wires' > excessive > side pressure on the bushing guide rail felt. Every new Steinway > grand I > have seen had this problem, even one recently that was "rebuilt" in > the > factory restoration dept. > I suppose the heavy pressure is allowed to make the dampers > appear to > travel straight, but it is false economy. The excessive pressure > causes the > bushing felt to wear, which causes the damper to migrate sideways, > which > causes the wedges to begin distorting, which causes increasing > "yowl" upon > return. It would also help if the treble-side tray support blocks > were fitted > snugly between the keybed and the bellyrail, since the loose ones > allow the > block to tilt, which allows the tray to move laterally, which causes > marginally traveled wires to bind. > I own a 1914 model O which has the original guide rail felt in > it, and > the dampers travel straight and true with the original bends in the > wire, so > I know it can be done. It just takes more care than many of them > are given > these days. > > > > Ed Foote RPT > http://www.uk-piano.org/edfoote/index.html > www.uk-piano.org/edfoote/well_tempered_piano.html > <BR><BR><BR>**************<BR>Shop Dell’s full line of Laptops now > starting at $349! > (http://pr.atwola.com/promoclk/100126575x1221881320x1201406166/aol?redir=http:%2F%2Fad.doubleclick.net%2Fclk%3B215218036%3B37264217%3Bz > ) > </HTML>
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