Hi, While not being very learned on this subject, it seems to me that the ribs supply two main functions. To support or maintain the boards shape and to help in transducing vibrations to the entire board surface. If the ribs or board are too massive they will act as a mute, and if too frail the system will fail. A balance, using the Roman arch principle, is what I envision in the perfect board. The edge of the board can be thinner in both board and rib becuase the rim supports the assembled board. Final coat of whatever, will change the tonal output of the board just like a violin or guitar. Joe Goss RPT Mother Goose Tools imatunr@srvinet.com www.mothergoosetools.com ----- Original Message ----- From: "Ron Nossaman" <rnossaman@cox.net> To: "Pianotech List" <pianotech@ptg.org> Sent: Thursday, February 16, 2006 9:32 AM Subject: Re: laminated ribs > > > If I understand rib tapering theory correctly (and maybe I don't - so > > please correct me), the straight tapering that Del and Ron O use is > > based on engineering principles that suggest such a design will best > > support a centered load more-or-less evenly along the length of the rib > > (and allow freedom of movement at the ends). Whereas the constant > > thickness rib with the sculpted tapers at the ends lends itself better > > to a compression-crowned soundboard where the constant thickness of the > > rib will tend to induce development of consistent crown as the panel > > hydrates (and allow freedom of movement at the ends). > > > > I realize there is everything in between also, but isn't that the big > > picture? > > > > Terry Farrell > > Sounds reasonable enough to me. One system designed to develop > crown, the other designed to support it. <G> > Ron N > _______________________________________________ > Pianotech list info: https://www.moypiano.com/resources/#archives
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