This is a multi-part message in MIME format. ---------------------- multipart/alternative attachment Why would this be better than simply creating a rib crowned and supported panel that can be compressed to the requisite stiffness through the use of downbearing without overstressing the panel? =20 David Love davidlovepianos@comcast.net=20 -----Original Message----- From: pianotech-bounces@ptg.org [mailto:pianotech-bounces@ptg.org] On Behalf Of Erwinspiano@aol.com Sent: Monday, April 11, 2005 6:34 PM To: pianotech@ptg.org Subject: Re: Virtual Ribs, A new crown support method =20 RIc May the force? be with you brother.grin Dale Hi folks After a few months of experimenting, I am ready to announce a new (I=20 believe) method of supporting crown for any type of soundboard. The=20 method allows for both restoring crown and supporting it in older=20 panels, and designing new panels in which the concerns of mass levels=20 and degree of assembly stiffness can be to a far greater degree treated=20 independantly.=20 In essence, an array of repelling high power neodym magnets of=20 appropriate dimmensions and strengths are used to support crown against=20 downbearing from the strings. One set are imbeded in soundboard button=20 similar wooden sheaths and are attached to the soundboard with glue and=20 screws. Opposing these is another set which are mounted into a very=20 strong wooden beam such that their distance from the soundboard attached magnets can be adjusted easily from below. One can either choose to=20 simply provide support directly under the bridge, or without too much=20 difficulty, contrive what amounts to a system of virtual ribs with fully adjustable support for crown. For edification... Neodym magnets that measure 30 mm =D8 by 5 mm thick = can hold / push approximately 25 kilos. Since there is no phsyical=20 connection between the soundboard and opposing magnets, the assembly is=20 not directly mass loaded. Hence stiffness and crown support is provided=20 without mass loading. More later on as I formalize an article on a working example I am hoping to finish soon. As is my habit... this is an open source idea, I encourage any and all=20 to take up and refine it in their own fashion. My own initial results=20 indicate that the principle is very successful. Cheers Richard Brekne =20 ---------------------- multipart/alternative attachment An HTML attachment was scrubbed... URL: https://www.moypiano.com/ptg/pianotech.php/attachments/60/46/37/0a/attachment.htm ---------------------- multipart/alternative attachment--
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