Plywood is quite important since it may be used for many functional applications in structural, exterior, and interior projects. It can be applied to a variety of jobs, including as paneling and formwork. What is plywood made of exactly, and how is it made?
In this article, we will address these inquiries and gain a deeper understanding of why plywood is a highly adaptable material for both outdoor and indoor building endeavors.
What Is Plywood?
It is a type of wood material made by bonding thin layers of wood veneer together, with each layer's wood grain rotated up to 90 degrees from the previous layer. Simply put, plywood is produced by layering wood veneers to form a uniform sheet.
Process
Plywood pieces are shaped differently based on their planned purpose. In case the plywood is intended for construction use, it is compressed into wide flat panels. When it is meant for use in building aircraft or boats, or for making furniture, it is shaped into curves. Each ply in the stack has its grain oriented perpendicular to the others.
By doing this, the likelihood of the layer constricting is reduced and its strength and longevity are preserved. Plywood is made up of three or more layers of wood joined together by adhesive.
The back and the face are the two exterior sections of the plywood. The back is usually unseen while the face is visible. The middle layer is known as the core, and if five or more plies are utilized, the extra internal layers are called crossbands.
Materials
The process of making plywood varies greatly depending on the materials used. It can be made from softwood or hardwood. Furthermore, it can be made using a combination of both. Softwoods such as cedar, pine, redwood, and spruce are often used in its creation; however, Douglas fir is the most commonly chosen species.
Typically crafted from oak, mahogany, teak, maple, or ash. If composite plywood is utilized, the center layer may be made up of either solid wood chunks or particle board. This is commonly utilized for projects that necessitate boards of significant thickness.
Wood layers can be joined together to create a plywood sheet using a variety of glue types. The intended application of the plywood dictates its type. For external applications, structural sheet materials might use phenol-formaldehyde resin, for example. This is because the glue is an essential component of any outdoor work because of its high strength and endurance against wetness.
If used indoors, typical adhesives are made from soy protein or blood protein. However, many interior plywoods now commonly use phenolic resins that are also found in exterior panels. Finally, when plywood is used in furniture construction, the adhesive is usually composed of urea-formaldehyde resins.
It can also be constructed from various materials. For example, depending on the project, a layer of paper, cloth, metal, or plastic may need to be affixed to the plywood's front, back, or occasionally both sides. This contributes to further improving the board's moisture resistance. This is commonly known as laminated plywood and is widely used in the transportation, agriculture and construction industries.
Plywood can be enhanced with a liquid stain layer for a refined appearance, commonly applied in decorative crafts. In conclusion, plywood can undergo treatment with various chemicals in order to enhance diverse characteristics. For instance, it can be modified to be more durable against fires or decomposition.
Classification
Plywood can be broadly divided into two categories, each having a unique grading scheme. Included are the hardwood/decorative class and the construction/industrial class. Plywoods in the building and industrial sectors are used because of their robustness. The strength of the veneer on both sides and its resistance to exposure are what decide their ranking. Depending on the type of glue used, the possibility to be revealed can occur on the inside or outside.
The classification includes veneer grades of D, C, B, A, or N. The D grade is the lowest with multiple defects while, while the N grade has minimal defects. Usually, plywood used for subflooring falls within the C to D rating range.
Plywood classified as hardwood/decorative, which is the second kind, is used because of its attractive appearance. How well the plywood can tolerate moisture will determine the grade for this course.
Since this plywood is primarily used for decorative purposes, its surface is usually flawless to the unaided eye. Type III, Type II, Tile I, and Technical make up the rankings.
Sizes
Plywood comes in a wide range of sizes. The width ranges from 0.6 to 3 inches, with 0.25 to 0.75 inches as the usual thickness used. Both the back and front of veneer must possess equal thickness, and the top and bottom crossbands must also match in size.
Due to its universal properties, plywood is suitable for use in almost any building or decorative endeavor. If you require additional details or are still curious about the process of making plywood, contact Miranda for further information.
