David, Probably just about everyone who has used any of these parts has this problem, potentially. For all of it's highly touted superiority, hornbeam, as used in (most) piano parts these days, has some (to me, anyway) serious drawbacks, the two worst offendors being mass and porosity. Mass you simply have to ignore or work out ways to reduce. Porosity issues vary as greatly as the micro-environments in which we all exist. My own solution, is to cook the new parts in a specially built box (a contraption devised by David Vanderlip). This artful construct is actually designed to hold even an Imperial stack, is constructed from 3/8" ply, and, in mine, has four 50 Watt DamppChaser rods. These latter are set up with one each in the middle of the bottom and the top, and two low on either side. There is a square hole in either end, through which go not only the cords for the rods, but also air from the old-fashioned "hatbox" style hair dryer. This is truly a wonderful device. An overnight experience for a troublesome stack in that heat will show up all sorts of nastiness. Anyway, for new parts, I heat them, then size the bushings, then heat them again, then repin whatever is falling out. Then, Heaven forefend, I use a Silicone and Naptha solution to help to seal the wood. (Yep, it creeps. No, I don't care; and, neither should you. What matters to the player is "does it work" not, "does it last 100 years". Yes, I know that this is a minority view. But, I don't have to go back to do very much repinning later.) At that point, chances are you will know if/how much things are loose to an unacceptable level. Often, the center pins holding in the springs are offenders. Clearly, these should not get the Silicone treatment. Instead, I most often simply glue them in place with a glue sizing. Remember that this pin is, in effect, not a pivot point, but acts only to hold the spring (relatively) in place. Besides, unless one has seriously screwed up, there is bushing cloth all the way around it. (The glue sizing I use is thick enough not to carry the glue into that area. If it _does_ get there, you get the _most_ annoyingly difficult to find clicking...ask me now I know this...) Anyway, your method sound just fine to me, and is certainly a darn sight less work. Sorry to have not responded to your earlier post. 7,6,5,4,3,2,...(oops! what comes after 2?) Best. Horace At 09:30 AM 5/7/1998 -0500, you wrote: >Awhile back I posted a question (I think on Pianotech) >concerning what to do to fix several sets of Renner wippens >that had centerpins walking out of their bushings on a >regular basis. It occurs only in the bushing holding the >spring in place. I never saw any responses, but I did figure >out a solution (I tried repinning,and the new pins came out >just as fast). I used music wire inserted though the bushing >and then bent in a U shape, to keep the springs in place. It >doesn't look real pretty (reminds me of the beckets in a >Hamilton) but I can't think of any problems likely to occur. >In any case, it is reversable-simply cut one bend off and >out it comes. >Something to keep in mind if you ever see this problem. It >only happened for a brief period of time, but I can't be the >only tech who ordered parts with this problem. >Eight Days and Counting >David Graham, RPT >Northern Illinois University >Dekalb Il > > Horace Greeley, CNA, MCP, RPT Systems Analyst/Engineer Controller's Office Stanford University email: hgreeley@leland.stanford.edu voice mail: 650.725.9062 fax: 650.725.8014
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