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Veneer is thin. Most of the time you don't even notice it, but if you hold a piece of fresh-cut plywood up at eye level and peer at the edge, you can see just how thin the veneer is. Typical veneer is usually no thicker than about 1/16 inch. It's bonded to the front of plywood with glue under pressure. It stays intact for a lifetime unless exposed to moisture, the glue fails or the edge of the veneer hooks on something and gets pulled loose. Other damages occur if the veneer is sanded too deep, scratched or gouged. You can repair almost any type of damage to veneer.
Loose veneer creates a flap, or a visible separation along the edge of a door. This type of damage is typically only a few inches long or wide. Repair loose veneer by inserting the tip of a putty knife into the crack. Clean out any loose chips or debris to allow the veneer to lay flat. Pry the flap up just enough to inject glue under it. If the flap won't lift up high enough, rub glue on the end of the knife and insert it into the crack, scraping the glue off inside and under the flap. If the veneer is bubbled, and has no visible cracks, cut a small slit into the bubble and inject glue into the bubble. Place a thin piece of plastic over the crack or bubble. Use a padded clamp with cardboard or rubber to pad the door, and apply enough pressure to the flap or bubble to smash it down flat. If the bubble is in an area that you can't reach with a clamp, place a heavy object on it. Allow the glue to dry for at least one hour. Remove the clamp. Scrape off any residual glue with the putty knife. If the flap is less than 1 inch deep or long, you can also use masking tape instead of a clamp.
One of the worst problems occurs when veneer is sanded off. This happens during the building process, or when you're refinishing or repairing the door. It creates a void that reveals the core of the lumber below the veneer. Repair this type of damage by coloring it to match the existing woodwork. Use a matching stain marker to color the area to match the existing veneer on the door. When the stain dries, drag the tip of a darker marker across the damaged area to imitate grain lines. If you can still see the damage, try drawing the grain lines with a colored pencil, or even use the tip of a knife to score the damaged area slightly to imitate the grain pattern. Rub some wood putty over it and sand it lightly with 180-grit sandpaper. Spray the area lightly with a single coat of aerosol lacquer. If you can still see the area, drag the tip of the marker over the lacquered area and spray it again.
You can sand out many scratches on veneer doors. Attach 100-grit sandpaper to a hand-sanding block. Sand across the scratch parallel to the grain, back and forth gently until the scratch is gone. Carefully monitor the sanding process to prevent sanding through the veneer. If the grain lines around the scratch begin to disappear, stop sanding immediately. Apply a matching putty stick to the remaining parts of the scratch, followed by a matching oil stain. Spray the area lightly with one coat of aerosol lacquer. Repair deeper gouges with wood putty. This type of putty is specific to species. Purchase the right putty to match the existing veneer on the door. Smash the putty hard into the gouge. Smear the putty to flatten it. When the putty is dry, sand the surface of the putty flush using 100-grit sandpaper. Draw grain lines on the putty using a stain marker. Finish by spraying lightly with lacquer.
Hollow core veneer doors sometimes separate. The outside plywood panel lifts from the frame of the door in one piece. This is often caused when something falls between the door and jamb. When the door is shut tight, it lifts the 1/4-inch veneered panel off the door at the bottom corner. Fix this damage by removing the door from the hinges. Place it across two sawhorses. Lift the plywood panel up as far as possible. Apply glue to the frame of the door under the plywood. Press the plywood back into place. Place padded clamps around the perimeter of the door where the plywood was loose. If the clamps won't reach far enough, place heavy objects in the center of the door to compress the plywood panel into the frame. Allow the glue to dry overnight before removing the clamps or the objects.
