How to Build a Wall-Mounted Pet Organizer

Place the crown molding in a miter box on an angle so that the deck of the box represents the underside of the shelf, and the fence represents the fascia board. Cut a 45-degree angle on each end so that the piece measures 24¾ inches, long point to long point. (This will make the shorter dimension equal to the width of the fascia board, or 22½ inches.) Cut one return 2¼ inches from square edge to long point. Cut a second return at 2¼ inches, with its square cut on the opposite end. Apply wood glue to the corner pieces and press them together. Holding the nail gun at an angle, drive 1-inch nails through the crown molding into the underside of the shelf and into the fascia board.