On Monday, April 11, 2016 at 7:06:55 AM UTC-4, dadiOH wrote:
DerbyDad03 wrote:
On Sunday, April 10, 2016 at 7:17:01 PM UTC-4, dadiOH wrote:
DerbyDad03 wrote:

Groove or on top of a batten? How is it attached to the sides? In
either case, how much do the sides extend below the bottom?

Grooves in the sides and front. The groves extend about 1/2" below
the bottom panel. The bottom panel is now kind of bowl shaped,
sagging
left
to right as well as front to back.

Simplest fix is 3 screws through the bottom into the back. Put one
in the center first, then one more on each side halfway between
center and side. That should fix the sag in both directions; if not,
slack off the last two, add another one (two more total) between
them and center, then tighten the loosened one.

Ah, if it were only that simple. To repeat what I just posted in
response to dpb's post...

I clamped the bottom of the drawers to the back of box in three spots,
completely closing the gap along the back. The front and sides of the
bottoms are fully seated in the grooves of the box. I placed a 36"
straight edge across the bottom of the interior of the drawers and
measured the gap between the straight edge and the bottom of the
drawer
at the center of the bottom.

3/8" on one drawer, 1/2" on the other.

And what happens if you push up on the bottom while it is clamped? Sag
disappear? If so, then either the bottom isn't fully seated in the grooves
or the grooves are too big. If not, try loosening the clamps THEN pushing.

OK, when I say fully seated in the grooves, I mean that as much wood as can
be seated with a *bowed* bottom is in the grooves.

Of course if the bottom is bowed the wood has to pull out of the grooves and
can no longer be fully, 100%, in the grooves.

Bottom line is that the bottom is bowed into a shallow bowl shape and
simply securely the bottom to the back of the box is not going to eliminate
the sag in the middle of the bottom. There is no way that your "simplest fix"
of 3 screws across the bottom into the back is going to flatten the 1/2"
sag in the center of the bottom. Yes, it will flatten the *back* of the
bottom but not the center of the bottom.