Lumber is derived from logs which are harvested, debarked, and processed into long pieces with a rectangular cross-section. The transformation of logs into lumber involves multiple steps, beginning with an automated saw that slices the log into slabs. These slabs are then transported via a conveyor belt to smaller saws, where they are cut into square-edged pieces of specific widths.
Initially, the surfaces of these lumber pieces are rough, and their dimensions may vary slightly from one end to the other. The cutting method of wood significantly influences the lumber's characteristics and applications. Lumber is cut in three ways: plainsawing, quartersawing, or riftsawing.
Plainsawn lumber displays growth rings nearly flat along the board's wider face and is commonly used in structural applications due to its efficiency in production and cost-effectiveness. Quartersawn lumber, in which the growth rings align approximately 45 degrees in softwoods and 60 degrees in hardwoods to the board's wider face, is preferred for products like flooring, trim, and siding because of its enhanced stability and appearance. Riftsawing, applied mainly to hardwoods, aligns the growth rings at a 30 to 60-degree angle, optimizing aesthetic appeal and durability, making it ideal for high-quality furnishings and decorative applications. Each cutting technique offers distinct advantages, catering to different needs in the construction and woodworking industries.
Long, rectangular pieces of wood used in construction are called lumber.
Logs harvested from trees are debarked and repeatedly fed through an automated saw.
Each time the log is sliced, the slabs are transported by conveyor belt to smaller saws. Here, the slabs are cut into square-edged lumber of the required widths.
At this stage, the cut pieces have rough surfaces, and their dimensions may slightly differ from one end to the other.
Lumber is obtained either by plainsawing or quartersawing. Plainsawn lumber portrays the growth rings of trees flat on the board's wider face and is typically used as structural lumber.
In quartersawn lumber, the growth rings align at roughly 45 degrees or more in softwoods and at 60 degrees or more in hardwoods to the board's wider face. Quartersawn softwood is used for flooring, trim, and siding.
Riftsawing is also used for hardwoods, with the growth rings in riftsawn hardwood aligning at a 30 to 60-degree angle to the board's wide face and used where appearance and durability are essential.
繁體中文
