Hi Don, I agree that for most purposes, 8 grams of friction in a shank would be excessive. I should have qualified the number: 1) Only on high use grands 2) with heavy-ish hammers 3) bass to tenor area 4) when done during high end of humidity cycle 5) in conjunction with application of Protek 6) with a cross check of minimum three swings I have found a fairly rapid drop in friction after re-pinning, somewhat similar to drop in torque when stringing, where after two to three months (granted, of heavy use, and possibly drop in humidity), friction will drop by at least a couple grams, and number of swings will increase from three to five, from four to seven, or so. In a sense, what I am doing is "floating" frictional parameters - making it too tight to begin with so it will be right longer. And removing as little felt as possible to preserve the bushings as long as possible. I typically use 3 to 5 grams for home or low use. And maybe my dry climate and low air pollution has a big effect on efficacy of these parameters. I do use a commonly available set of tools known as "Mannino broaches" (hmmm, maybe some relative of yours, Don <g>), and rough up the felt as little as possible, in conjunction with solid burnishing. BTW, I have found those broaches can vary quite a bit. I bought two sets over time, one for home, one for school, and the first set was great. The second had extreme roughness in the cuttin area - real deep spirals. Not hard to get around. I just made my own rough spots a little down the wire, and don't get into the pre-made rough. But it may be something to watch for. Also, the same second set had nasty burrs by the sharpened end, so that it would cut felt while being inserted in the bushing (easily removed with a file or sandpaper). As long as I'm on the subject, I like to replace the rather bulky handles with home made ones out of 1/8" dowel. This is plenty of handle for the purpose, and allows me to carry the set with me in a very compact kit made of a small square of firm corrugated cardboard - just press the broaches through the corrugations (don't insert in the corrugation holes, go cross wise and puncture each corugation). The square goes with my nice new pinning tool by Mike Calahan (boy is it nice to have zero wobble/side play. Definitely my favorite purchase from the Dallas convention) and pin nippers into a small pouch made of mackintosh. One more thought: I sure wish there were two more sizes in these broach kits - up to 22 1/2 centerpin (.055). And I sure wish action makers would revert to starting off with 19 centerpins, instead of 20.5 or so. Regards, Fred Sturm University of New Mexico --On Tuesday, September 30, 2003 7:49 PM -0700 Don Mannino <dmannino@kawaius.com> wrote: > Hi all, > > I don't believe the emralon treatment of the action center bushings in > Steinway pianos hardens the felt in any way. I agree that the action > will perform better with at least some friction, though. I wouldn't pin > at 8 grams for hammer centers, though, unless you are really roughing up > the felt a lot when reaming (and therefore want to build in a little > compensation for later loosening). 8 grams should only be needed if the > felt is really soft stuff - which is not the case in Steinway parts that > I have seen. > > In this type of new piano situation, I would probably only burnish the > bushings with music wire, then fit them for 2 - 4 grams friction in the > hammer centers, measured at the screw hole. > > This should definitely not increase the touch more than 3 or 4 grams - I > find that a change of 1 gram friction in Steinway hammer centers results > in a change of about 1.5 grams at the key. If you also repin the wippen > centers then that could push it up a little higher - but there isn't > much reason to add friction there unless they are really sloppy. > > Don Mannino > > > -----Original Message----- > From: caut-bounces@ptg.org [mailto:caut-bounces@ptg.org] On Behalf Of > Fred Sturm > Sent: Tuesday, September 30, 2003 9:37 AM > To: College and University Technicians > Subject: RE: Steinway "pinning" dilemma > > > Hi Jim, > I share your bafflement. I have heard the same things from > various > Steinway techs - "as long as it's firm, friction doesn't matter." I > agree > with Jeff, Ed, Horace and others. In my experience, friction does > matter, > and I want 4 to 8 grams in my shank centers (paying attention to ambiant > > humidity at the time). I do a lot of top action repinning as a matter of > > standard up-keep. Typically every year or two for a performance > instrument. > I find this makes a big difference to sound production, responsiveness, > control, nuance, function (helps a lot in the checking versus rep spring > > strength balancing act). So I am puzzled when I hear the opposite view > from > techs I respect. > My sense is this is possibly a matter of tail wagging dog. When > teflon was > abandoned, instead of going back to regular old felt, Steinway went to > this > felt impregnated with Emralon, Permalon, or whatever it is exactly. I > have > the feeling this was partly a production driven innovation (aimed at > more > consistency with less labor), with the idea that it would also lead to > improvement in function. With this impregnation, the felt can be more > variable in density and fit, and the "plastic substance" makes the > bushing > longer lasting and less liable to humidity fluctuation. It is also > readily > soluble, so you just dose with methanol to free or (at least sometimes) > firm up the center. And there is the shock absorbing attribute of felt > as > an improvement over the teflon. > All sounds great in theory. But in practice it becomes difficult > to > impossible to come up with free movement plus standard parameters of > friction under production conditions. Regular felt bushings are fit to > standards by controlling density and thickness of the felt used, and > then > by applying an appropriate shrinking formula after pinning. Shrinking > formulas don't work with felt impregnated with "plastic substance." The > felt is no longer controllable, except by reaming, which is too > labor-intensive for factory application. So they have to make sure the > felt > is thin (or lacking density) enough to be free, and fill in the gaps > with > the plastic. Meaning there is no possibility for achieving what most of > us > agree is optimum friction parameters. Though they _can_ achieve good > firmness with low friction consistently. > Result being that, decisions having been made and production > facilities > long since adapted, they try to make the best of it. At least that's how > I > read it. > I'd be very interested to hear what Eric has to say. As it > happens, I'm > heading to NYC for a week long seminar the end of October, and this > whole > question was high on my list of things to query. Eric says he won't be > there (he'll be on the competition circuit somewhere), so I'll ask Kent > and > whoever else is available and see what they have to say. This question > is > similar to the whole hammer treatment issue (especially Ron Coners > saying > the only part of the hammer that matters is the crown, and limiting what > is > done to 3:1 lacquer and single needles deep into the crown, along with > occasional application of keytop). I hear what they are saying, and > hesitate to reject it outright, but I just can't seem to digest it. > Doesn't > compute. Doesn't fit with my experience. On the other hand, the C & A > department in NYC is dealing with, and satisfying, the cream of the > cream > pianists, day after day, year after year. Who am I to argue? It's a > quandary. > Regards, > Fred Sturm > University of New Mexico > > --On Saturday, September 27, 2003 7:43 PM -0600 Jim Busby > <jim_busby@byu.edu> wrote: > >> >> >> David, >> >> >> >> You may be right about the capstans and knuckles, but once again it >> means changing a new instrument x 8. Eric Schandall is coming out next > >> week and I'll push him hard on this. Let's see what he says. I was >> told by "a competitor" that concert artists will never like them as >> is, but if this is what Steinway C & A is doing I can't really buy >> that either. >> >> >> >> As far as side play goes they really do seem tight. (no excess >> sideplay) But the things swing all day long! If this indeed works, >> then all the PTG literature, articles, etc. about friction are in >> question. Or maybe there really are two types of pianos; S & S, and >> everyone else. >> >> >> >> >> >> Jim Busby >> > > _______________________________________________ > caut list info: https://www.moypiano.com/resources/#archives > > _______________________________________________ > caut list info: https://www.moypiano.com/resources/#archives
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