I don't suppose you have any pictures of what was done to fit a Mason/Hamlin tensioner in the steinway? It's amazing what techs will try on a piano... David Ilvedson, RPT Pacifica, CA 94044 ----- Original message ---------------------------------------- From: "Scott E. Thile" <scott.thile at murraystate.edu> To: "College and University Technicians" <caut at ptg.org> Received: 9/25/2007 8:34:01 AM Subject: Re: [CAUT] Gravalla Tension regulator >Interesting article, Ron. I stand corrected in terms of the direction of the >forces at play... >It would be interesting to know what would happen in your model if the board >were glued into the jig like it would be in the piano. I suspect capturing >the board by gluing it down (after it's crowned) could still contribute to >resisting forces by preventing the ends from moving as freely (regardless of >the direction). >Even if stiffness of the rim assembly does not contribute to retention of >the crown and/or downbearing, it does effect tone production. My experience >is the effects are dramatic, especially in projection, and especially in the >"killer octave". My point is that regardless of the effects of maintaining >crown, stiffness in the rim assembly seems to be is an important factor. >Back to the original question. I like the wood stiffener as well as the >other method's Steinway uses to achieve stiffness in the assembly. That >stiffener would appear to be an attempt to address the killer octave, and I >think it works. I recently rebuilt a D with a new board, and I replaced that >little stiffener, as well as lots of other work to rim and braces, which had >been significantly compromised in order to include an M&H tensioner at one >point. It's hard to know if any of that contributes to the success of this >piano or it's just benefiting from the new healthy board. >Steinway's methods of stiffening the assembly seem to work really well, and >they seem to hold up at least as well over time as other methods. I would >not want to eliminate one of them in order to install another.... >In pianos, Scott >Murray State, Murray, KY >> -----Original Message----- >> From: caut-bounces at ptg.org [mailto:caut-bounces at ptg.org] On >> Behalf Of Ron Nossaman >> Sent: Monday, September 24, 2007 10:26 PM >> To: College and University Technicians >> Subject: Re: [CAUT] Gravalla Tension regulator >> >> >> >> > The piece that is in there is intended to stiffen the belly >> rail, and >> > it works. My understanding is that it is under tension as >> opposed to >> > compression. It's pulled end to end as it holds the bell rail from >> > pushing out under the down bearing on the board. If you >> picture that >> > it's easier to understand it's size than if your thinking >> compression >> > like the beams. >> >> The belly rail won't push out from downbearing load. If >> anything, it'll pull in. Soundboard crown isn't an arch. See >> April 2006 Journal, "Rib crown as an End-Buttressed Arch". >> >> Ron N
This PTG archive page provided courtesy of Moy Piano Service, LLC