PICKING 3/4 INCH OAK VENEER PLYWOOD FOR STRENGTH

[BT98]

I just built a bookcase from 3/4 oak plywood with real oak wood for trim. I copied this from another bookcase that we purchased about 12 years ago. I am finding the shelves in mine are sagging from the books. The old book case with same style and crafted shelves does not have this problem. I was told that the core material in the newer plywoods is crap and that is the problem. How do you pick plywood for strength? I noticed in Home Depot the other day they had Oak plywood that was stamped made in China on the edge and it looked far superior to quality than what I used and was made by Boise. Any comments?

[bf]

Well, I used to buy oak plywood from home depot.. Back when they charged $50/sheet, it was pretty good quality (for B grade).. Now it's down to $40/sheet, and it's crap.. the veneer comes off and there's lots of Huge voids.. I had a project where I had to recut because under the veneer was a huge void.. like 3 inches by 2 inches.. Fortunately, when I was handling it, my finger broke through.. I would've really been mad if that happened after the project was done.

Unfortunately, I bought 4 sheets of that crap, so it's going to be used as garage shelves now.. Sadly, I have to drive 2.5 hours now to get good oak ply at a reasonable price.

[Juergen Hannappel]

Plywood is unsuited for bookshelves. You want either solid boards or core board, with the grain of the core part along the long side of the shelves.

[Pat Barber]

[BT98]

The shelves are 12"X 40". I know now that in place of just edging the shelf I should edged it with a 1 1/2 strip.

[Chris Friesen]

That's a pretty drastic statement.

Plywood works just fine for bookshelves, as long as they are suitably designed with the limitations of the material in mind.

Certainly it's not as strong as solid wood, but you don't always need that strength.

Chris

[Jerry]

At 40" even a hardwood shelf probably would have sagged.

[Puckdropper]

"BT98" wrote in news:1143729753.776958.225060 @i39g2000cwa.googlegroups.com:

*snip: Oak Plywood sagging and low quality...*

Put a back on your shelves. It will prevent books from falling behind the shelves as well as stiffen and strengthen everything. If you use strong enough material for the back, you can even secure the shelves along the back.

Alternatively, you could add a 1x2 to the back of the shelf, which if placed on the base of the shelf would prevent books from being pushed back too far and give you some fairly straight lumber to straighten the shelves.

Puckdropper

[Juergen Hannappel]

Yet I uphold it.

Plywood (with it's many thin layers) is a nice material, but strength against bending over long lengths is not its bets property.

For bookshelfes solid core board is as good as solid wood at a lesser price, and is the preferred material if you want hardwood bookshelves.

Juergen

[RayV]

[BT98]

I just got an Eagle America catalog today and they have a new item listed - Extruded Aluminum shelf stiffeners. They are 48 inches long and take a 3/4" shelf. Look on page 86 of the spring 2006 catalog.

[Bradford Chaucer]