Plywood

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Plywood a panel consisting of an assembly of thin sheets of wood (ie veneer) bonded together with an adhesive where the grain direction remains in alternate plies, usually at right angle. Timber species, thickness, and grain direction of each layer are matched with those of opposite side of the core. The total number of layers is odd (three, five, or more). The major steps in the manufacture of plywood consist of veneer preparation, veneer drying, slicing of dry veneer, mixing and spreading of resin, pressing, conditioning, and finishing by trimming and sanding.

The major use of plywood in Bangladesh is for making tea chest. The other uses are internal decoration of buses, aircrafts, cabinet making (wardrobe, table, dresser, etc.), house building (wall, ceiling, floor, door, etc), sports goods, etc. In Bangladesh, there are about 25 factories producing commercial plywood and tea chest; majority are located in Chittagong and the Chittagong Hill Tracts.

The Bangladesh Standards and Testing Institution recommends 16 timber species for decorative veneer and decorative plywood, 17 species for marine plywood, 46 species for manufacture of plywood for general puposes, 36 species for plywood and battens for tea chests. Some of the species are susceptible to fungi and thus require preservative treatment with borax, boric acid or zinc chloride. The principal species for plywood in Bangladesh are Civit (Swintonia floribunda), Uri Am (Mangifera sylvatica), mango (Mangifera indica), Garjan (Dipterocarpus species), Chapalish (Artocarpus chaplasha), Chickrassy (Chuckrassia tabularis), and Korai (Albizia spp). '[MA Sattar]

See also timber tree; wood.