Qustion about wood movement?

[Brian Knop]

I am building a cabinet. The side are made of soild quarter sawed oak. The plan I have calls for the bottom to be made from soild wood also. Here's the question. If I were to use plywood instead would I have a wood movement problem? I know that the oak will move and that the plywood will not.

Thanks Brian

[David Rose]

Brian, are you thinking of using the plywood on the bottom only? If so, I ran some numbers on the Wood Movement Calculator. Our local humidity will run from 25% to 65%. QSWO 12" wide will move .155". If the bottom is used for rigidity of the cabinet, as in fully "glued in", I would be concerned about that much movement. Other more experienced folks can probably give you a more sure answer, but I wouldn't do it. If you don't need the bottom for rigidity, you might glue only the front few(?) inches and float the rest in a dado. I think the glue would fail with movement and time if glued full depth of the cabinet. That would still give you some support if partially glued.

David


I am building a cabinet. The side are made of soild quarter sawed oak. The plan I have calls for the bottom to be made from soild wood also. Here's the question. If I were to use plywood instead would I have a wood movement problem? I know that the oak will move and that the plywood will not.

Thanks Brian

[Jim Becker]

Brian, I agree with David...using plywood for the bottom will complicate things. Personally, I'd use solid stock. If that bottom is not visible, you can always use a secondary wood that is more affordable with similar movement characteristics. (Be sure you're comparing it to the movement numbers for QS oak...)