Hi Wasson, Ten years ago,I did a test about the elasticity modulus of spruce,here is the average value of the "vibrational modulus of elasticity". E(l)=7.854 GPa E(t)=0.537 GPa E(l) is the modulus along the grain(fibre),E(t) is the modulus across the grain, GPa = 10^9 Pa = 1,000,000,000 Newton/square meters. "Vibrational modulus" is the modulus of elasticity at the vibration state.The value of "Vibrational modulus" should be a little smaller than that of the "steady modulus" because of the special characteristics of wood. As you know,the characteristics of wood varies a lot according to the kind of spruce, the way you cut the log,etc' . The wood I tested is from north China,it's a little softer I think.So the modulus'value of the spruce you are using could be a little higher. Hope it helps! Baoli Liu Shenyang Conservatory of Music China > At 99-11-18 23:53:00, you wrote: > >Does anyone happen to know, or know where I can find, approximate typical values for the modulus of elasticity for spruce both along the grain (the rib) and across the grain (the soundboard)? This comes up because the technician installing the new sound > >board for me wants to decrease the width of the new ribs yet leave unchanged the stiffness of the soundboard/rib assembly. Obviously, the new ribs will need to be taller, but how much? Armed with enough facts, I am confident that I can figure this out w > >ith some practical degree of accuracy. > > > >Wasson Kerrick, RPT > >Owensboro, KY > >wkerrick@mindspring.com > > >
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