- 1). Wash the medium-density fiberboard with a pressure washer. Allow the MDF to dry for 24 hours.
- 2). Apply a small amount of stain to an inconspicuous area of the medium-density fiberboard. Allow the MDF to dry for two hours. Evaluate the appearance of the finish before proceeding with that stain.
- 3). Place the boards on a drop cloth or spread a drop cloth beneath immovable boards.
- 4). Coat the medium-density fiberboard with the oil-based stain of your choosing. Brush horizontally, using a three-inch china paintbrush. Brush only a three-foot wide area at a time. Wipe down the wet MDF, using shop rags. Proceed until all of the medium-density fiberboard is stained.
- 5). Wash the brush with mineral spirits.
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