Fred, My broach kit goes from 48-55 which was purchased at KC convention several years ago. Blaine Kent State At 07:39 AM 10/3/03 -0600, you wrote: >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 > > >_______________________________________________ >caut list info: https://www.moypiano.com/resources/#archives
This PTG archive page provided courtesy of Moy Piano Service, LLC