John,
>3. Isn't a hard glue joint a high impedence structure, more likely to
>reflect sound back, than to pass it on to the rest of the board
It would seem to me that a hard glue joint is more acoustically
"transparent". but as you say in #4.
>doesn't most of the sound get from the bridges to the outside of the
>board through the ribs anyway?
Steinway still uses hot hide glue to join the planks up with, and we used it
in school, ( with a mad Englishman over our shoulder saying "Hurry up!).
I now use Tite-bond, but I still hurry. This is how;
place a strip of masking tape as close to the edge of the groove as
possible, then lay a bead of titebond along the length of the tape. The shim
is then laid on the glue bead, flipped over and the other side of the shim is
laid on the glue, and then the shim is pressed in. Total time between
wetting the shim and wedging into the groove is about 6 seconds. The tape
allows you to scrape up the excess glue, and if everything is clean, you can
pour it back into the glue bottle. The tape also provides a surface to pencil
in an index mark to match one on the shim for locating.
I have many repairs like this in my customer base, and they all seem to
be very durable.
I know there are other ways to do this, and I am all ears 8;)
Ed Foote
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