Whether you're painting or sanding a wooden door, taking time to ensure a even, smooth final surface creates a clean and finished final product. To smooth out a wooden door, you have to sand it. Homeowners looking for a quick fix sometimes perform a quick, rough sanding, but doing so can create more problems than solutions. In addition to looking unsightly, the hills and valleys created by a rough sanding job exposes more surface area, which requires more stain for complete coverage, according to national repair columnist Tim Carter. Sand wooden doors correctly for best results.
Remove the wooden door from the door frame. Lay the door horizontally across two sawhorses. Cover the rests on the top of the sawhorses with soft, clean cotton cloths to protect the door.
Sand the flat surfaces of the door with an orbital sander loaded with 80-grit sandpaper. Sand as much of the door as possible with the sander, but avoid getting too close to decorative moulding or edging and possibly damaging the door. Sand the door a second time using 100-grit sandpaper, then a third and final time with 120-grit sandpaper to achieve a flat, smooth finish.
Fold a piece of 100-grit sandpaper and use it to hand-sand any areas inaccessible to the orbital sander. Use long, smooth strokes to give the door the most even finish possible. Switch to a 100-grit sanding sponge to reach any interior sections that cannot be sanded comfortably with the folded sandpaper.
Vacuum the entire surface of the door using a vacuum with a soft brush attachment to remove most of the sand and wood residue.
Flip the door over and repeat the process, including the vacuuming. Wipe down both sides of the door with a soft, clean cloth after all wooden surfaces are sanded and vacuumed to remove any lingering dirt or debris.