Straightening Unsupported Plywood Shelf

[Bart Harris]

I have made a bamboo plywood cubby to sit on top of a topless drawer unit.

The bottom of the cubby will be unsupported but is slightly bowed. There is no space to add any kind of thick support to straighten it. The drawer front underneath will highlight the bow because the gap will be huge in the middle.

Any ideas how to keep this thing straight? Thanks.

[Andy D Jones]

Is the back of the bottom of the cubby also unsupported? Or is there a back to which it can be fastened?

What if you added a base to the whole cubby? It need only raise the base up 1.5 to 2 inches (depending on how wide the cubby is). Just a ring of 4 wood pieces on edge, under the cubby (could be flush with the outside of the cubby).

You could also replace the bottom of the cubby with a torsion box (two sheets of ply, separated by vertical cross-pieces for rigidity, and wrapped around the edges for additional rigidity and appearance). Depending on how wide/deep this piece is, it needn't be more than a couple of inches thick.

-- Andy - Arlington TX

[Paul F Franklin]

A pic would be helpful. Can you add a piece inside the drawer unit that you could screw through into the bottom of the cubby to pull the bowed piece down?

[Jamie Buxton]

Bottom shelf? Cut it out, and insert a flat piece. You should be able to cut it out with a tablesaw.

[Richard Coers]

A pic would be helpful. Can you add a piece inside the drawer unit that you could screw through into the bottom of the cubby to pull the bowed piece down?
How about a pic of that topless drawer unit. Maybe it's NSFW?

[Keith Westfall]

Build a small torsion box for the top

[Paul F Franklin]

how about a pic of that topless drawer unit. Maybe it's nsfw?

lol............

[Jim Becker]

Bart, photos would be very helpful for folks to provide assistance and ideas relative to your described situation. Please click on the Donate button up at the top of the page and become a Contributor so you can post photos. That also gets you access to private messaging, the Classifieds and some other features not available to folks who are not Contributors.

Jim
Forum Moderator

[Bart Harris]

The back is unsupported—and straight!— but i could definitely pull it down to bend the front a little.

No room for anything else because i have made the drawer maximum height and if I cut it down then biscuits will show. I could remake it but would rather not.

I sealed the underside the same as the top side so I'm hoping that it might naturally balance itself.

Thanks for your help :D

[Bart Harris]

This is a fantastic addition to Andy's suggestion. I could definitely attach a piece between the drawer unit and cubby at the back, to pull the back of the cubby down. This should hopefully give enough tension to affect the front.

Many thanks.

[Bart Harris]

No room for that sadly, but thanks. I think I have my answer: I will pull the back down and brace it so the front follows suit.

[Bill Dufour]

welded angle iron frame screwed to box sides. painted to blend or covered with thin veneer.
Bil lD