Sanding a cupboard's doors is a necessary step in finishing the cupboard, and sometimes it is as simple as applying a hand power sander to the door. However, most cupboards usually have decorative detailing, and this fine detailing must be preserved from the effects of harsh power tools. For that reason, sanding most cupboard doors is a little more complicated than it seems.
Step 1 - Remove the Doors
Detach the doors from the cupboard. Since wanting an unobstructed surface for sanding, do this by unscrewing the door from the cupboard hinges.
Step 2 - Take off the Hardware
Remove any handles or knobs. Usually, this means unfastening the relevant screws on the inside of the door, but some knobs are screwed in with their own built-in screws and can be unscrewed directly and without a screwdriver.
Step 3 - Sand Large Surfaces
Sand large, flat surfaces with a handheld rotary tool fitted with a 60-grit sanding disc if the door has an existing finish or coat of paint. This will remove the bulk of the finish/paint. Sand the open, flat surfaces again, this time using a 120-grit sanding disc. If the cupboard doors are unfinished, skip to Step 5.
Step 4 - Sand Details
Sand the decorative detailing of the door with a coarse-to-medium grit hand sandpaper (such as 80-grit) to remove the old finish or paint. This will be a tedious and time-consuming task, but it is necessary to avoid removing too much wood and disfiguring the detailing. Always sand with the grain of the wood. If the cupboard doors are unfinished or there is no detailing, skip to Step 5.
Step 5 - Re-Sand
Prepare the cupboard door for painting or finishing by sanding it with fine-grit sandpaper. Use a handheld rotary tool fitted with a 240-grit sanding disc for the easy, flat parts of the doors, and fine-grit (180- to 240-grit) hand sandpaper for the detailing, if any.
Tips & Warnings
Avoid pressing down on the wood with the handheld rotary tool, since using too much force will cause the circular motion of the tool to leave squiggles in the wood surface.
Wear safety goggles and a respirator mask whenever you use power tools for sanding.