What are 3 common defects in wood?

Common Wood Defects: Types & Causes of Lumber Issues

• Checks and Splits. A check is a term used to describe a crack that runs through a board, usually running lengthwise.
• Rot and Decay. Rot and decay is the general description for the disintegration of wood fiber.
• Ring Shake.
• Pitch, Gum and Sap.
• Wane.
• Crook or Crown.
• Bow.
• Cup.

What are the common defects of timber?

Types of Defects in Timber as a Construction Material

• Wind Cracks in Timber.
• Shakes in Timber.
• Twisted Fibers in Timbers.
• Upsets.
• Rind Galls.
• Burls.
• Water Stain.
• Chemical Stain.

What is a shake wood defect?

Shakes are natural occurring defects in standing trees caused by a lengthwise separation of latewood fibers. The bacteria that causes shake enter the trees through the roots and not through the stem. The bacterium belongs to the clostridium genus and is often accompanied by an unpleasant odor.

What is timber shake?

Shakes are cracks in timber. When found in a log they can result in a significant amount of waste, when a log is converted to lumber. Apart from heart shakes, often found in trees felled past their best, shakes in a log have no effect on the strength of shake free lumber obtained therefrom.

Why do shakes form in Timber?

Various causes are suggested, such as felling across obstructions, and failure inside the growing tree caused by high winds, growth stresses, etc. ls also known as Felling Shakes, Thunder, Rupture, Lightning, and Transverse Shakes, Upsets, Cross Breaks, or Cross Fractures.

What causes end splits in Timber?

What Causes End Splitting? End splitting is the result of moisture content changes which are more rapid at the exposed end grain of timber – the stress created by this movement can result in splitting.

What causes end splits in timber?

What are the common defects found in the timber and what are they due to?

The followings are the five main types of defects in timber:

• Defects due to Natural Forces.
• Defects due to Attack by Insects.
• Defects due to Fungi.
• Defects due to Defective Seasoning.
• Defects due to Defective Conversion.

What does checking mean in wood?

A check is separation in wood fibers across the annual rings of a piece of wood and a split is a separation of wood fibers across the annual rings but through a piece wood.

What is a split in wood?

Splits and cracks in wood are ruptures or separations in the grain of the wood which reduce the quality as measured by appearance, strength, or utility. Many people assume that all splits and cracks in wood are caused by the dry kiln or the drying operations.

What causes checking in wood?

The Short Answer: Wood Checking Splits and cracks (known as wood checks in the industry) occur when wood shrinks as it dries. Wood shrinks roughly twice as much along with the growth rings (radially) as it does across the rings (tangentially). It is this uneven shrinkage that causes checks to develop.