>Ron, > >This seems a good idea. I see that you say that the rib is 60% >stiffer than a conventional rib. Is it as light or lighter than a >conventional rib? > >Phil Ford Hi Phil, They are 25% lighter than a 25 mm X 25 mm rib at their centre where the bottom flange is full width. Once the bottom flange is tapered they become lighter still. This works very well in the mid to low bass areas where less weight is a distinct advantage. However, the treble requires a certain mass to function properly. We keep the treble ribs deeper than usual in the treble to maintain mass and to increase their load carrying capacity. The uppermost ribs for many conventionally ribbed pianos only measure around 20 X 20 mm, which is possibly a bit light on. The I-rib is about 10% heavier than ribs of that dimension. I've got another page nearly ready which shows the ribs under test on the bench. Might get it up tonight. Ron O. -- OVERS PIANOS - SYDNEY Grand piano manufacturers ________________________ Web: http://www.overspianos.com.au Email: mailto:ron@overspianos.com.au ________________________
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