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Types of Lumber

Types of Lumber

Lumber - edged and unedged boards, edged and unedged timber, slats, planks, slabs - products obtained by sawing logs at a sawmill. There are several ways to classify lumber - according to their cross-section, the degree and type of processing, the location of the wood inside the log, the moisture content of the wood and the type of cut

The Following Types of Lumber Sections Are Distinguished

  • Timber is lumber of rectangular or square cross-section, the thickness of which is more than ten centimeters, and the width is no more than twice the thickness.
  • Lumber is lumber similar to timber, only less than ten centimeters thick.
  • Board is a rectangular lumber having a thickness of up to ten centimeters and a width that is more than twice the thickness.
  • Obapol is lumber, also called slab, made from the side of a log, having one or two sawn planes.
  • Lath - thin boards and small flat bars.
  • Plank - boards that have a small width and length.

According to Processing, the Following Types of Lumber Are Distinguished

Lumber is of the following types:

  • Unedged - the side edges are not sawn and look like the outer part of the log.
  • Single-sided - in this case, only one edge remains unprocessed.
  • Edged - this type of lumber has all four edges sawn.

According to surface treatment, lumber is divided into:

  • Unplaned - lumber that has not been subjected to additional processing.
  • Planed - lumber that has undergone additional processing by planing and sanding, due to which its surface becomes smooth and even.
  • Milled - in such lumber, from one to four edges are milled.

Depending on the Location on the Cut of the Log, there Are the Following Types of Lumber

Depending on which part of the log cut the lumber is made from, they differ as follows:

  • Core - lumber consisting of the core of a log, the least quality lumber.
  • Center lumber - lumber in which the core of the log is sawn lengthwise, the quality is slightly higher than that of heart-shaped lumber.
  • Lateral - lumber in which the core of the log is absent; this is the highest quality type of lumber.

The Cut is Also Taken into Account when Classifying Lumber

Depending on the angle at which the log is cut, lumber is distinguished:

  • Cross cut - the cut is made across the grain of the wood.
  • Radial cut - the cut is made perpendicular to the annual rings.
  • Tangential cut - in this case, the cutting is made tangentially to the annual rings.

Lumber is Also Classified by Moisture Content

The original wood has a moisture content of more than 60%, so before delivery to the consumer, lumber is subjected to natural or artificial drying. Depending on the technology of drying lumber and the final moisture content, the following types are distinguished:

  • Natural drying - such lumber has a moisture content of about 18-27%.
  • Chamber drying - artificial drying allows you to reduce wood moisture content to 8-16%.