A veneer is a thin slice of wood with its thickness determined by the end use. There are two major classifications of veneers:
-
Constructional
-
Decorative
Constructional veneers are produced mainly for plywood and laminated veneer lumber (LVL). Plywood consists of an odd number of laminations of veneer bonded at right angles to each other to equalize shrinkage and improve engineering properties.
Decorative veneers are produced to display aesthetic surface appeal. There are four major types of markets or uses for decorative veneers:
- Architectural
- Secondary manufacturing, such as furniture and cabinets
- Profile-wrapped mouldings
- Paneling
Veneer companies are usually very selective in which logs they can use. However, each company has its own specialized markets, and therefore the quality of logs that are acceptable varies from one company to another
LAMINATING PROCESS
The major steps taken by Indian companies to overlay /laminating of decorative veneer on the back plywood are as follows
- When the decorative veneer sheet is laid on plywood core, its grain should always be at right angles to that of outermost veneer of the plywood, otherwise cracking and checking can result.
- Moisture content of veneer and substrate at the time of gluing and pressing is the one of the most important factors in achieving high quality panels. Veneer panel producers must check the moisture content values of veneers and boards prior to gluing to ensure user confidence in veneered board. In particular, it should be noted that the majority of veneers are imported from overseas and are produced under different environmental conditions. Their moisture content could also change during transport in shipping containers.
- The moisture content of both veneers & substrate should be checked shortly before gluing. It is essential that the moisture content of the two materials be held at about the same level in order to eliminate high stresses due to differential movement.