As it became clear that making MDF offered a far better use of residual wood than disposing of it, production soared. Today there are some 27 plants in the US and Canada, and more than 100 worldwide. Recovered wood scraps are bound together with an adhesive resin and compressed under high heat. MDF is typically made from sawdust, planer shavings and other waste that remains after a tree is milled into lumber. The wood is then cleaned and mechanically refined in a process that reduces it into fine, uniform fibers.
Excess moisture is removed and an adhesive resin is added to hold the fibers together.
This mix is then formed into a long, thick, homogeneous mat, which is compressed under intense heat and pressure. The resulting MDF panel is sanded to a fine, even smoothness, and cut to the required width and length. Computer-controlled sensors monitor the entire manufacturing process to measure slight variations that even the human eye cannot detect. Finished panels are tested for uniformity, strength and other structural soundness. MDF is used extensively indoors in furniture, cabinets, doors, mouldings and flooring.