soundboardinstal again

[Farrell]

Installing the board with tension? Seems that would be quite a trick!

If butting the panel up to the outer rim snugly preserves the circle of sound, won't the sound simply leak out the edge of the panel along the belly rail?

Terry Farrell
  
----- Original Message ----- 
From: "Isaac sur Noos" <oleg-i@noos.fr>
To: "Pianotech" <pianotech@ptg.org>
Sent: Monday, July 21, 2003 5:30 AM
Subject: RE: soundboardinstal again


> Ron,
> 
> Me think (may be wrongly) that on the opposite, the fact that a so
> small dimension is involved show us the importance of a better joint
> (last news from the day !)
> 
> The inserting under tension of the soundboard seem the only way to
> have some tension in the panel, in the rib direction (across grain)
> the modulus of elasticity is said to be 3 Kg cm2 vs. 100 Kg cm2 in
> direction of grain.
> So if we wish to have some tension in the panel that looks like a
> convenient method, more than compression crowning.
> 
> Stephen have forced back some boards with shims on the straight side
> with good results he say, when we see the dimensions involved, that
> looks like a possibility.
> 
> The panel is said to be shaped with 1 cm more than the internal size
> of the rim, was said. If possible a soundboard that should be pinched
> in the rim should work better from an acoustical point of view (a very
> good joke to future rebuilders !)
> 
> Idem on the belly rail, while some brands have stopped the insertion
> there (Seiler for instance).
> But I seem to understand that in the actual conception in the USA the
> soundboard assembly is viewed as an auto supported device is not it ?
> 
> Greetings
> 
> Isaac OLEG
> 
> Entretien et reparation de pianos.
> 
> PianoTech
> 17 rue de Choisy
> 94400 VITRY sur SEINE
> FRANCE
> tel : 033 01 47 18 06 98
> fax : 033 01 47 18 06 90
> cell: 06 60 42 58 77
>