> The PianoTek Treble Tone Resonator I believe is designed to be tightened > once installed so as to slightly pull the rim toward the belly rail. Well, it's more likely to slightly pull the belly rail toward the rim. > Your rods are stationary as compared to this? Give similar effect? plus the > mass load. They should both do something roughly similar, which is to eliminate some of the belly rail's flexibility by attaching it to the rim. The tone resonator has a means of tightening because it can't be the exact size needed for all pianos without some possible adjustment. One thing I like about the bars is that the bar goes clear through the belly rail, providing support all the way to the front edge, where it's most needed. > More curiosity: > I have often wondered what direction the force against the belly brace > beams > is. Are the typical wooden beams supporting a load in one or both > directions > paralell to the beams? Which direction? > It would make sense that the case would tend to expand under string load?? > In that case would it not make sense that beams should be dovetailed into > case and bellyrail as opposed to just mortised? > > Gene String downbearing levered to the front edge of the belly rail should make it want to rotate forward and down, but being glued to the soundboard, it won't go far. Ron N
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