Hi Del, I'm glad to hear this. I've been arguing with local people for years that horizontal laminations in bridges were getting a bum rap, but what I was saying was contrary to what they'd heard, etc, etc. You know the drill. Thanks. Ron At 01:13 PM 12/9/97 -0800, you wrote: > > >Ron Nossaman wrote: > >> Hi Newton, >> >> It would split twice as fast? If it were taller than it was wide, would it >> "break off" with a major pitch raise? How about "flagpoling bridge syndrome"? >> >> The splitting part brings me to something I wanted to ask anyway. Is there a >> reasonable body of empirical evidence that horizontally laminated bridges >> are evil, or is it just that since they are found on evil pianos, it's >> assumed? Have horizontally laminated bridges been actually installed in >> decent pianos and tested? >> >> Ever a "lert" and in anticipation, Ron >> >> Ron Nossaman > > ------------------------ > >The idea that horizontally laminated bridges were a bad thing is a holdover from the days when folks were concerned about the >speed of sound through the glue joint. The idea was that if it was different from that if the wood it would somehow upset the >sound wave. > >Piano bridges are just that -- bridges. They have mass and they have stiffness. There are a variety of ways to design and >build good bridges and just as many ways to design and build bad bridges. Horizontally laminated bridges can be designed to >work just as well as either solid body bridges or vertically laminated bridges. Mostly it's a matter of what the manufacturer >is tooled up to make. If you are making more than just a few pianos, vertically laminated bridges are easy to make. All it >requires is a simple press and a male and female caul. If you have CNC milling machinery, then horizontally laminated bridges >are easy to make. > >My personal preference is a vertically laminated body and a horizontally laminated cap. This combines the ease of manufacture >of the vertically laminated body and the excellent termination qualities and durability of the horizontally laminated cap. > >Solid body bridges are pretty much a thing of the past for most practical purposes. Not only is good material is too hard to >come by these days, but it's not a good idea to bond laminated stock to solid stock. The expansion and contraction rates are >quite different, hence the often seen delaminated bridge caps. > >-- ddf > > Ron Nossaman
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