Plywood

Plywood was the first type of engineered wood to be invented. It is made from thin sheets of wood veneer, called plies, which are stacked together with the direction of each ply's grain differing from its neighbors by 90° (cross-banding). The plies are bonded under heat and pressure with strong adhesives, usually phenol formaldehyde resin1, making plywood a type of composite material.

History

Plywood has been made for thousands of years; the earliest known occurrence of plywood was in ancient Egypt around 3500 BC when wooden articles were made from sawn veneers glued together crosswise. This was originally done due to a shortage of fine wood; thin sheets of high-quality wood were glued over a substrate of lower-quality wood for cosmetic effect, with the structural benefits arising only incidentally. This manner of inventing plywood has occurred repeatedly throughout history; for example, many of the great English furniture makers such as Sheridan used veneer as a raw material.

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Modern plywood in which the veneer are cut on a rotary lathe from softwood logs is of relatively recent origin, invented by Emmanuel Nobel (the father of the more-famous Alfred Nobel). The first such lathes were set up in the United States in the mid 19th century. Plywood has been one of the most ubiquitous building products for decades.

Related Topics:
Lathe - Emmanuel Nobel - Alfred Nobel - United States - 19th century

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Compare to OSB (Oriented strand board) and MDF (Medium-density fibreboard).

Related Topics:
Oriented strand board - Medium-density fibreboard

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