Hi folks After a few months of experimenting, I am ready to announce a new (I believe) method of supporting crown for any type of soundboard. The method allows for both restoring crown and supporting it in older panels, and designing new panels in which the concerns of mass levels and degree of assembly stiffness can be to a far greater degree treated independantly. In essence, an array of repelling high power neodym magnets of appropriate dimmensions and strengths are used to support crown against downbearing from the strings. One set are imbeded in soundboard button similar wooden sheaths and are attached to the soundboard with glue and screws. Opposing these is another set which are mounted into a very strong wooden beam such that their distance from the soundboard attached magnets can be adjusted easily from below. One can either choose to simply provide support directly under the bridge, or without too much difficulty, contrive what amounts to a system of virtual ribs with fully adjustable support for crown. For edification... Neodym magnets that measure 30 mm Ø by 5 mm thick can hold / push approximately 25 kilos. Since there is no phsyical connection between the soundboard and opposing magnets, the assembly is not directly mass loaded. Hence stiffness and crown support is provided 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 to take up and refine it in their own fashion. My own initial results indicate that the principle is very successful. Cheers Richard Brekne
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