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To sand a lot of molding, glue 80-grit sandpaper to several inches of the molding. Rub a block of Styrofoam on the sandpaper until the block conforms to the molding’s contour. Glue sandpaper to the block, then sand the molding.
This method works best on large cove moldings; small rounds or hollows can loose their definition if sanded with a large block and coarse paper. -Tebor Narom
