Soundboardcrown

[Marcel Carey]

Peter,

Here are my results and procedure:

I started with ribs that were crowned to a radius of 65 feet.
Made cauls that had a average radius of 47 ft
Dried the soundboard to a 4.48 % MC (Moisture content)
When I took the board out of the press, I had a crown of 45 feet
radius; now, after a week I have 3/8" between the longest ribs (45.5")
which gives me a radius of 57.5 feet. I'm quite happy with this crown
(Mason & Hamlin "A").

Maybe Del will have a different opinion, and I hope he will share his
thoughts on these figures.

Marcel Carey, RPT
Sherbrooke, QC

> As you can think already, the press is not curved, but if I
> decide to
> curve it, what's the amount you suggest?
> >
> > Typically, if you are going to depend on just the curve of
> > the rib-to-soundboard press to form your crown you would want
> > to end up with a whole lot more than 3/8" crown (on the
> > longest ribs) when it comes out of the press.
>
> Does this also means that one looses a certain amount of crown a few
> days, weeks after the board came out the press?
> >
> > This is why very few, if any, shops attempt to crown
> > soundboards in this manner.
> >
> > Del
> >
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> >
>
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