Soundboard installation with hide glue

[John Delacour]

At 00:30 +0100 16/1/08, StŽphane Collin wrote:

>...Do you think at some caveats, or do you have special advice for this
>situation ?  I already understood that I need one or two helpers in order to
>spread the glue very quickly.

I hope you have better heating than I have!  Heat is the key to jobs 
like this, not only a warm environment but, more important, warm 
wood.  Adhesion with animal glue is achieved by "mechanical adhesion" 
and "polar adhesion".  Provided the wood is warm enough to keep or 
return the glue to above the gelling temperature while the parts are 
brought together, then the needs of mechanical adhesion are 
satisfied, that is to say that the tiny "fingers" or better "claws" 
of glue can penetrate as deep as possible into the roughness of the 
surface and, in the case of most hardwoods, the pores.  To be able to 
clamp down the board before the glue gels is, of course, most 
desirable.  Ideally there should be no gap to fill, and inspection of 
the glue line on Victorian pianos shows that there is practically no 
glue between the rim and the board.

As to the tonal superiority of animal glue over, for example, a good 
epoxy glue suitably thickened, I doubt if there is any.

JD