Extra Strong and Waterproof, What is Plywood?
What is Plywood?
Plywood is a wood-based material in the form of thin panels. This material is glued crosswise at a 90-degree angle to each other and is formed from an odd number of wood sheets.
Reporting from Start Word Working Now, plywood has different qualities according to the desired product. The quality of plywood mostly depends on the gluing or the number of veneer layers used. Actually, plywood has existed since ancient Egyptian times. This is evident from the pieces of furniture made of plywood found. Unfortunately, plywood management was forgotten and not used again until the mid-19th century.
During the industrial revolution, plywood became popular and was produced in large quantities. This is because plywood is widely used in the automotive industry and aircraft construction. This material is widely used in various fields, ranging from building materials, furniture, to ship frames due to its water-resistant properties. Moreover, this material is easy to bend compared to most conventional wood.
Plywood manufacturing starts with peeling the tree trunk which is then steamed and softened. This is done to unroll the trunk into flat sheets.
Multiple layers of wood are then glued and pressed together, alternating with the direction of the wood grain. This is what gives plywood its durability despite its shape.
To glue the sheets of wood together, a panel-sized press is used to make chipboard panels. Usually, in the plywood production process, phenolic glue (waterproof glue) is used.
The last process in plywood production is sanding to smooth the surface of the plywood sheet.
Some types of plywood are also coated with special compounds such as melamine or acrylic. The most widely used woods for plywood production are softwoods such as Spruce, Birch or Poplar.
Plywood has great strength and high dimensional stability. Due to the interlocking effect of each layer, plywood has better expanding and shrinking properties compared to solid wood panels.
Source: kompas.com