2. MDF in wrapped mouldings
Wood veneer or foil wrapped MDF mouldings are widely used as alternatives to solid wood mouldings by furniture and fitment manufacturers. Well established applications include the frames for solid and glass panel doors, mirror surrounds, cornices and pelmets in fitted kitchens, decorative trim for facia panels, structural rails in kitchen units, drawer sides and handles. The recent availability of MDF up to 60 mm thickness allows deep mouldings to be cut directly without the need for laminating thinner boards to build up the required thickness.
A. Core Materials
Wrapped mouldings can be manufactured with cores machined from MDF, low grade solid wood, or particleboard. The main advantages of MDF over these other materials are :
1. Freedom from twisting or bowing associated with grain irregularities in solid wood.
2. Supplied in long lengths ready to use at the right moisture content.
3. Compatible dimensional stability with other wood based sheet materials, consequently no risk of bowing when fixed to panels manufactured from these materials.
4. Close packed fibres throughout the thickness of MDF ensures good machining and freedom from showthrough or other appearance defects associated with the use of more open core materials such as particleboard.
B. Surfacing Materials
Real wood veneer wrapped MDF mouldings are widely used to match the grain and texture previously obtained with solid wood mouldings with the added advantage that the veneers can be selected for uniformity of colour and freedom from natural defects associated with solid wood. Standard wood veneers, typically 0.6 mm thick, are used for wrapping simple mouldings. Continuous finger jointed lengths of wood veneer with cotton mesh (fleece) or paper backing are available for wrapping mouldings with tight profiles.
Alternatively, paper or PVC foils in plain colours or with printed decorative effects, wood grains for instance, can be successfully wrapped round MDF mouldings.
Most wrapped mouldings are manufactured using hot melt or two component polyurethane adhesive but some companies offer a higher durability product bonded with urea formaldehyde adhesive for applications where exposure to high ambient temperatures is a possibility.
Where the ends of the wrapped moulding are exposed on an item of furniture, the MDF can be covered effectively with a matching heat transfer foil.
The good machining characteristics and high internal bond strength of MDF are put to good effect in the construction of panel doors using wrapped mouldings to make mitre jointed frames. The success of this type of door depends upon the accuracy of cutting the mitre angles and the strength of the dowel or loose tongue reinforced corner joints.
Specialist wrapped moulding suppliers throughout Europe offer a wide range of wood veneer or foil wrapped mouldings. Some of the larger kitchen and domestic furniture manufacturers have set up wrapped moulding lines to satisfy their own needs.