Remove the hinge-posts and the door hardware, then inspect the damaged areas. The door's peep-hole will be removed by filling it with a wood plug. The old doorknob opening is filled with old wood-filler, and the wood in that area is showing signs of rot.
Later, a wood-consolidant (also known as wood stabilizer) will be used to strengthen the wood fibers of the rotted areas and return some of the wood's structural integrity. For large areas of damage, consider replacing the damaged wood with a new section of wood. For smaller areas of damage and doors to be repainted as in this project, remove any loose or dry-rotted pieces.
The door in this project had latex paint applied over oil paint. It's often very difficult to sand latex paint, especially when it's applied over oil paint. Without removing this paint, the repairs we made to the door could not be sanded smooth. This meant that the paint would need to be removed using paint-stripper. An added benefit from stripping the paint is revealing the design details of the door hidden by many layers of paint.
Remove the door from the opening, place it on saw horses and lay down drop cloths. This is a job best done outdoors. If you work inside, be sure that there is adequate ventilation.
Apply the paint stripper as directed by the instructions on the container (Image 1). Let it set as long as specified in the directions.
Scrape off the paint with a wide putty knife to remove most of the softened paint. Finish removing the paint with a quality paint scraper tool (Image 2). Wide scrapers work well on flat surfaces. Pointed and shaped scrapers work well for corners and details.
Repeat the process until nearly all of the paint is gone and the wood exposed.
Neutralize the paint stripper with an appropriate liquid product as directed on the stripper instructions.
Sand the door as needed. For a door to be finished as natural wood, completely remove every bit of paint and sand thoroughly. For a door to be repainted, sand rough spots until the door is smooth and ready for paint.
Sand down the paint around the hole to bare wood, being careful not to over-sand.
Measure the size of the hole. Cut a piece of wood to the proper dimension to fill the hole. The plug should be the same thickness and diameter as the hole left where the peephole was removed. It's best to use the same type of wood as that of the door. This is important, not just for looks, but so that all of the wood will expand and contract at the same rate. (All wood expands and contracts to a certain degree based on environmental factors such as temperature and humidity.)
Using carpenter's glue (yellow glue), place the newly cut plug into the hole and allow the glue to set as per the manufacturer's recommendations. In our case, we secured the plug with quick-bonding wood filler to bond the plug and fill in any small gaps (Image 1). You may need to tap the plug into place with a hammer. Place a wooden block between the hammer and plug to avoid marring the surface of the plug.
After the glue has dried, scrape off any excess and sand again.
Using a putty knife, apply wood filler around the hole to cover any voids and make the finish surface smooth (Image 2).
When the wood-filler has dried, sand the area to prepare for primer and finish coat. We flipped the door over and used a belt sander to sand the plug flush with the surface of the door on the opposing side (Image 3).
For areas of soft wood (nearly dry-rotted), use a rotted-wood stabilizer. Use a chisel or scraper to remove any badly rotted areas or old wood filler (Image 1).
Apply the stabilizer (Image 2) according to the manufacturer's instructions and let it dry until the wood hardens.
Sand down the paint around the damaged area to bare wood. Remove any dust.
Using a polyester or epoxy resin filler, fill the damaged area to the surface and cover any voids (Image 3). This will harden to a tough surface ideal for attaching the hardware screws. Allow the filler to harden as per the manufacturer's instructions.
Sand the finish surface smooth. First use a flat rasp, then rough-grade sandpaper and finally with finishing grade sandpaper.
Sand the finish surface smooth, starting with a medium-grit 120 sandpaper, and finishing with a fine 220-grit.
Remove all dust from the surface, first with a brush and then with a tack cloth or clean, soft cloths.
Apply a primer coat to the door surface and allow it to dry. If the primer coat doesn't cover well, lightly sand it and apply a second coat.
After the primer hardens, sand the surface lightly with a 220-grit sandpaper. Remove all sanding dust as described above.
Apply an enamel top coat. Use the type of enamel appropriate for your situation. Be sure to use a quality paint brush, made for enamel paint, and that's at least 2-1/2" wide. This will help lay down a smooth surface of paint with a minimum of brush strokes.
To put the finishing touches on our door, period-authentic door hardware was essential. For this project, we visited Rejuvenation, a restorer and supplier of antique hardware. Restoration specialist Bo Sullivan helped us select some hardware that was appropriate to the style of the home. Most importantly, the company was able to completely restore some of the door's original hardware, such as the door latch, by re-plating the surface.