On 04/11/2016 8:59 AM, dpb wrote:
....

The alternative is, as also noted elsewhere and by others, use some
external stiffener either on bottom or inside the drawer--another ploy
in that regard that makes some more significant changes to the piece is
to add a middle divider so that you have another support in the middle
like the back. That, of course, changes the piece more but can be done
without terrible damage so can be (mostly) reversed but would leave signs.
....

BTW, presuming the bottom is still solid but just bowed, you can do the
divider trick w/o actually attaching it directly to the front so the
modification evidence is minimal if taken out. The bottom is
constrained by the groove at the edge and held in place by the brads at
the rear plus you can go thru the rear side so when the bottom is
brought up to the bottom of the divider it (the divider) can't go
anywhere; the bottom has to come up to it. That's for front-to-back;
side to side you've got grooves both ends.

For the one I recall specifically did for wife's shop I actually took
the bottom out, used a hand router plane and cut a stopped dado for the
divider in the front inside and pinned it to add some extra rigidity.
It was even wider than yours, though, 42" iirc...was a buffet-like
piece, not a dresser.

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