How to Straighten Warped Oak Boards Already Glued to a Hard Surface
- 1). Introduce heat to the board if the convex side is facing out. Apply heat to dry out the board by covering it with an electric blanket. Introduce moisture to the board if the concave side is facing out. Introduce moisture by covering the board in steaming hot towels. Leave the electric blanket or towels on for one to two days. Periodically replace wet towels as they dry out with hot towels. If you are repairing a convex side-out board and it is sticking up enough, wedge hot towels into the back side at the same time you are heating and drying out the front side.
- 2). Dab or drizzle wood glue underneath any parts of the board that have lifted away from the surface after removing the electric blanket or towels. By this time much or all of the warping may have gone away.
- 3). Clamp or place weights (anything from barbell weights to cinder blocks to cans of paint can be used) on the board and allow the glue to dry for at least 12 hours. If screwing or nailing is appropriate for the setting, screw or nail the board to secure it and ensure that it will not warp again. Use a wood filler that matches oak to cover and conceal screw or nail heads.
- 4). Finish and seal the board if appropriate.
- 5). Try to locate and stop the source of the moisture to prevent future warping. Caulk and seal any nearby seams that might let in moisture from outdoors. Repair any nearby drips or leaks.