Q:

What are some common defects in timber?

A:

Quick Answer

Common defects that occur in timber include knots, shakes, wind cracks, upsets, twisting, cupping, bowing, rot and insect damage. These defects are typically grouped into three categories: defects caused by natural forces, defects caused by defective seasoning and conversions and biological defects.

Know More
What are some common defects in timber?
Credit: Michael Blann Digital Vision Getty Images

Full Answer

Knots, shakes, wind cracks and upsets are defects caused by natural forces. Knots are the hardened stumps of broken or sawn branches, which can weaken or disfigure the surface of timber. Shakes are cracks in the timber caused by excessive heat, frost or twisting due to wind. Wind cracks are the cracks that appear on the outside of a log due to the shrinkage of the exterior surface. Upsets are defects in the grain caused by excessive compression or crushing of the tree when it is young.

Twisting, cupping, bowing are defects caused by defective seasoning and conversion. Twisting occurs when constriction causes the edges of a piece of timber to move out of parallel. Cupping is when the timber dries out in a curved shape. Bowing is a warp along the length of the face of the wood.

Rot and insect damage are biological defects. Rot most often occurs due to the presence of fungi in the timber. Insects weaken the timber because they eat the wood.

Learn more about Building Materials

Related Questions

  • Q:

    What natural resources are present in Cuba?

    A:

    The most common natural resources of Cuba are cobalt, nickel, iron ore, chromium, copper, salt, timber, silica, petroleum and arable land. The by-products of arable land in Cuba, namely sugar, tobacco and rum, are the most important export items of the Cuban economy.

    Full Answer >
    Filed Under:
  • Q:

    What is a malamute-wolf hybrid?

    A:

    A dog that is a cross between a timber or gray wolf and an Alaskan malamute is known as a wolamute. As with any wolf hybrid, these dogs tend to be more intelligent than most domestic breeds, according to Dog Breed Info Center.

    Full Answer >
    Filed Under:
  • Q:

    What materials were used to build the Parthenon?

    A:

    The Parthenon of Ancient Athens was made of hand-carved pentelic marble from top to bottom, with some timber to support the slanted marble tiles of the roof. The segments of the columns were internally secured by iron clamps with a layer of molten lead. The statue of Athena Parthenos inside the Parthenon had ivory skin and nearly 2,400 pounds of gold armor, weapons and jewelry.

    Full Answer >
    Filed Under:
  • Q:

    What are the causes and effects of illegal logging?

    A:

    Increased demand for timber, paper and forest products; flaws in forest governance and forest markets; forestry policy failure; corruption; and poverty are some of the causes of illegal logging. While trade-in timber is of economic importance, many timber consumers such as the European Union, have no legal way of stopping the import of illegally sourced forest products.

    Full Answer >
    Filed Under:

Explore