On 04/11/2016 9:07 AM, dadiOH wrote:
....

Which means that you have to get the bottom fully into the grooves. Or, at
least, far enough to remove the "belly". Once there, a couple of screws
through the bottom into the sides should take care of it.

The length of the arc for a 1/2" sag in the center for a chord length of
36" is 36.0185" -- thus the movement on either end of the bottom is only
about 0.01". Not significant. There's no chance you can prevent that
kind of movement in wood w/ a mechanical fastener from the side (besides
the damage done to the piece in trying to do that).

The question is, why did it bow in the first place? I can only think of two
reasons...
....

The most probable reason it bowed was that it had too much weight stored
in the drawer for 100+/- year and it's simple relaxation over the
unsupported span. No different than setting the set of encyclopedias or
a 100-lb bust of Beethoven on a long, unsupported bookshelf and leaving
them there--over time the shelf _will_ sag unless it's far more than
just a 3/4" ordinary shelf. In this case, we don't know what was in the
dresser, but whatever it was was too much for a minimal initial design.
1/4" is not enough material for a 36" drawer for anything but the
lightest of loads.

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