A hole in your front or back door is not only unpleasant to look at, but can get a little chilly as well. Doors are expensive and replacing them can be a time-consuming procedure. If you've recently replaced a door knob or have a small hole in your door, a little time and effort can fix it without a major renovation.
Cut a piece of dowel with a hand or skill saw that is the same size as the hole -- or very close to it. Allow the dowel to be a little bit thicker, about 1/32 inch thicker, according to Renovation Headquarters, than the thickness of the door.
Cement the dowel into the hole with exterior epoxy. If the dowel doesn't completely fill the hole, fill the gaps in with spray foam insulation.
Let the epoxy set completely.
Sand the dowel and epoxy down until it is flush with the door. Wipe the dust away with a tack cloth and paint or stain the door as necessary.
Mix up a small batch of auto body filler according to the instructions on the can. Stir it thoroughly and add the amount of catalyst, which hardens the mixture, required by the instructions.
Fill the hole in your metal door with the filler. Use a putty knife to add a dollop at a time.
Scrape the filler flush with the door and allow it to cure the recommended length of time.
Sand the filler down in crisscross patterns with 36-grit sandpaper. Sand until the surface is completely level, don't worry about it being smooth until it is level. According to Collision Blast, trying to get the finish smooth too soon can result in lumps.
Add more filler if there are still lows and repeat the sanding process.
Allow the filler to completely cure for about 20 minutes. Paint with a primer.
Sand the primer with 80-grit sandpaper. Dust with a tack cloth,
Finish with paint to blend with the rest of the door.