Matthew, One thing I discovered when I started replacing keybushings back in the 90's, was that it was easy to have them come out too loose. I like a firm balance rail bushing with only a few thousands of play. If you use standard 146 cauls and leave them in to dry, your balance rail bushings will be too loose. Nobody ever told me this when I was starting out! Bill Spurlock sells a set of balance rail cauls that are not oversized like the standard ones. These will leave the bushings a little tighter. Even so, I pull the cauls out after about 15 minutes to allow the bushings to expand slightly. This seems to get them very close to where I like them. Also I prefer the balance rail bushings to have ears. Others prefer to have them cut flush with the top of the key, but I see no advantage to this. By stretching the felt over the top of the key, I believe it puts a little tension in the felt which I feel is beneficial. Additionally, the ears sit up about a millimeter or so above the surface of the keybutton - this gives slightly more support - again, another advantage from my viewpoint. If anyone knows of a functional advantage of having the cloth cut flush, I'd like to know what it is. Of course, *hot hide glue is the correct glue to use.* It gels on the surface of the felt, leaving it more resilient, and it is easier to replace the bushings in the future. For getting old bushings out, I find it is best to soak them first before using the steam. Formula 409 seems to work the best! I mix it with 50 percent water. I use small wedges cut from hammer scraps that are small enough to fit into the mortises. These get soaked in the solution and inserted into the keys. If you leave them overnight they may dry out, so it is best to cover them with plastic wrap. In the morning you will find that they will usually almost fall out with no steam needed. Sometimes a little steam will still facilitate removal. On Sat, Jul 11, 2009 at 3:00 PM, Matthew Todd <toddpianoworks at att.net>wrote: > I will be doing a balance rail bushing job soon, and just wanted to see how > replacing the balance rail differs from replacing the front rail, i.e., the > key buttons. I am assuming I can take off the old ones using steam. And > then, what would be the best cauls to purchase. > > Thank you for the advice, > > ***TODD PIANO WORKS* > Matthew Todd, Piano Technician > (979) 248-9578 > http://www.toddpianoworks.com > -- Ryan Sowers, RPT Puget Sound Chapter Olympia, WA www.pianova.net -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://ptg.org/pipermail/pianotech.php/attachments/20090711/bbab85bf/attachment.htm>
This PTG archive page provided courtesy of Moy Piano Service, LLC