MDF (medium-density fiberboard) is a press-wood product commonly used for underlayments in many home construction projects. The wood is sturdy, resistant to warping and holds fasteners like nails and screws securely. MDF typically is sold in sheets meauring 1.2 x 2.4 m (4 x 8 feet) and in a variety of thicknesses, ranging from 1.3 to 5 cm (1/2 inch to 2 inches). The properties of MDF make it a good choice for a shelf-building project.
Lay your 2.5 cm (1 inch) thick sheet of MDF on a pair of saw horses. Line off the board into four 30 cm x 2.4 m (1 x 8 foot) sections with a measuring tape and pencil. Cut the board on the lines so you end up with four 30 cm x 2.4 m (1 x 8 foot) MDF boards.
Cut two of the boards in half horizontally to make four 30 cm x 1.2 m (1 x 4 foot) boards.
Position the two 2.4 m (8 foot) boards and two of the 1.2 m (4 foot) boards to make a hollow box that measures 1.2 x 2.4 m (4 x 8 feet) around the perimeter. Nail the boards together using a hammer and finishing nails.
Slide the remaining two 1.2 m (4 foot) boards into the box, positioning them so they're parallel to the 1.2 m (4 foot) boards and two feet away from each. Nail the 1.2 m (4 foot) boards in place with a hammer and finishing nails.
Place the 1.2 x 2.4 m (4 x 8 foot) sheet of 1.3 cm (1/2 inch) MDF onto the rectangular box. Nail it onto the box with nails spaced every 10 cm (4 inches) around the perimeter.
Sit the shelving system up so that it is sitting on the 1.2 m (4 foot) edge. Move the shelves to the spot where you want them.
Wear eye protection when using saws or other tools.