Luan vs Plywood "What about the snap factor"

[Dee Bee]

Although I am not a carpenter, I think there are some of the differences between luan and 1/4 " plywood. Maybe we can get a message string going by listing varioous experiences with both materials. I know that in one sense luan is a type of plywood. But I have observed the following as characteristic differences between 1/4" construction plywood and finish luan:

-thickness of the outside veneer (greater in plywood)
-strength of the core under the veneer (greater in plywood)
-flexability bendability(I think it is also greater in plywood)

This last point may be debatable. But here is how I see it.
By flexability I mean the ability to stress the sheet out of its flat profile before it will break. What do you think?

Luan appears floppy and many think this means it is easy to bend. It is up to a point. Then its britleness appears and the luan snaps under the stress all at once. This is why there are post on the forum asking how to bend luan without it breaking. Plywood of the same dimension feels stiffer, but it will bend, and will bend farther before structural failure.

Luan is cheaper because it is designed to be hung in sheets on flat surfaces. The core of luan is not the same as the core of other plywoods. Look at a cross section. Plywood is more expensive because the flexibility and strength come from more criss-crossing layers in the core of the sheet.

How do I know? I actually damaged a sheet of luan in Home Depot learning this lesson. I took a 1/4" sheet of ply and started to bend it. I noticed how stiff it felt. Then I took a 1/4 sheet of luan and started to apply the same comparative pressure to it in a bend and the sheet snapped before I got anywhere close to the same curve I had acheived in the plywood "test"

I didn't want the look of plywood inside my TD so I used oak veneer covered ply from HD. They also carry a beautiful birch product. Oak veneer was $18.90 sheet. Not nearly as cheap as luan, but I think the veneer oak looks classy.

There is a place for all kinds of wood products in building a TD, and plenty of room for all styles of construction. Tell why you like or use one product over another.

DEE

[madjack]

...we were going to use 3/16 bead board in the Alligator Tear. We started it bending using a pair of staps and over a couple of days pulling it into the desired radius(2'). It pulled into shape just fine and we set aside to just sit and "age" as it were. Came into the shop this morning and found bead board snapped in half and laying flat...after a week it had absorbed no memory. Allthough it does not look quite as good, we will be going to 1/4" bendy ply which comes from the Amazonian Flexitree Since I have pulled this product into a 2or3" radius, I don't think 2' will be a problem
madjack

[mikeschn]

Allthough it does not look quite as good, we will be going to 1/4" bendy ply which comes from the Amazonian Flexitree Since I have pulled this product into a 2or3" radius, I don't think 2' will be a problem
madjack

Wow, an Amazonian Flexitree? Where'd you find that, in the Garden of Eden?

I've only had a moderate amount of success bending a sheet of plywood against the grain. I eventually gave up and just started bending it with the grain. What a difference. I built the entire Baja Benroy with the grain... And you wanna fight mother nature? Not me!!!

Mike...

[ahjones3]

Somebody please correct me if I'm wrong. As far as I know, all cheap lauan you find at the homecenter is imported from who knows where. Also as far as I know it isn't graded by anybody. Hd & Lowes buy the cheapest stuff they can find. It's usually close to 1/4" and pretty smooth on one side, but other than that, you don't know what you'll get.
Al.

[Woody]

I had no problem bending 1/4" Luan over a 20" radius with the grain running parallel with the ground. I would not attempt bend longways due the tendency of luan to have voids in the center layer causing a weak spot and that is why it snaps. On my new teardrop I will do it again on the double 20" radius that mine has on the front