Medium density fiberboard, or MDF, is a manufactured composite wood product very similar to particleboard but a much denser end wood material. It is made from scrap wood dust and fibres that are pressed together. MDF is used for many projects and woodworking applications and is a good choice for many woodworkers because of its building qualities.
MDF is a mixture of refined wood chucks and shavings that are ground into a fine fiber.The wood is heated prior to refining to give the finished product a stronger and more moisture-resistant surface. During refining, the wood is rubbed apart into fibre bundles (Reference 1). A binder or wax resin is added, which is usually urea formaldehyde, and the product is then heat pressed, sanded and sawn into very dense sheets. It requires about 23 inches of a fibre/resin mix to create one ¾-inch sheet of MDF, whereas it only takes about 4 to 6 inches of wood chips and sawdust to create one sheet of ¾-inch particleboard.
Most MDF is flatter than plywood and warps much less frequently. MDF is presanded, which makes it nice for quick lamination projects. It comes in 100 different wood species and cuts, including some speciality ones. Another feature of MDF is that it has no grain, which makes it a stable material that is smooth, flat and uniform. MDF cuts well leaving a smooth edge, and it also can be painted easily with a coat of primer first and then paint.
MDF costs about twice as much as particle board. It is sometimes hard to find to purchase since many DIY and lumberyards don't usually carry it. MDF may have to be bought through a builder's or cabinetmakers supply company.
One of the ingredients in MDF, formaldehyde, has been linked to possible health problems and is a possible carcinogen, so you should cut or sand MDF outdoors and with a mask or respirator and goggles, if possible.
MDF is used for furniture, shelving, laminate flooring, decorative moulding, doors, mantles and many other woodworking applications. It is a good insulator for sound and heat. MDF is very easy to work with and versatile since it takes well to nailing, gluing, screwing, stapling and attaching using dowels.MDF's uniform surface makes it a perfect material for wood veneers and plastic laminate.
The standard size for MDF is 4-by-8 foot sheets in various thicknesses, while the largest sheets are usually 5 by 12 feet. The standard thicknesses are 1/8 inch, 3/16 inch, 7/16 inch, ½ inch and 11/16 inch.