Question: Why Do Shakes Form In Timber?

What are defects in timber?

A Defect is taken to be any irregularity occurring in or on the timber which may lower its strength, durability, utility value or diminish its appearance.

Defects may be ‘natural’ which occur whilst the tree is growing, or ‘artificial’ as a result of poor conversion, seasoning or handling after felling..

What is the most expensive wood?

THE MOST EXPENSIVE WOOD IN THE WORLDGrenadil, African Blackwood. This wood is one of the most expensive on the planet. … Agar Wood. Agar wood is a valuable plant found in tropical forests of Southeast Asia. … Black wood (Ebony) … Sandalwood. … Amaranth, Purple Heart. … Dalbergia. … Bubinga. … Bocote, Cordia (Bocote, Cordia)

How can you tell if wood is Sal?

When freshly cut, it is identified by its light color and coarse grain. However, exposure to sunlight darkens its wood.

Is wood checking bad?

Normally even severe log checking is not a structural problem; it’s cracking along the grain of the log, almost never continuing all the way through the log body, and is a normal result of building with wet or green logs.

What are three lumber defects?

Top 9 Lumber DefectsBow: A bow is a curve on the face of a board, typically extending from one end to the other. … Check: A check is a crack that occurs along the wood’s growth rings. … Crook: A crook is a warp that happens along the edge of a board.Cup: A cup is when the face of a board is hollow.More items…•

What is knots in timber?

Knots are imperfections from branches that cause living wood grain to grow around them. … Dead branches drop off healthy, living trees all the time, and wood knots appear in the trunk where branches died.

What are the causes of wood defects?

There are innate defects caused by the natural characteristic of wood to shrink or expand in response to water vapor in the air. And, there are artificial and mechanical defects caused by incorrect sawing or machining (conversion), improper drying (seasoning), or improper handling and storage.

What does it mean when Wood checks?

Splits and cracks (known as ‘checks’ in the industry) occur when wood shrinks as it dries. Wood shrinks roughly twice as much along the growth rings (radially) as it does across the rings (tangentially)–and it is this uneven shrinkage that causes checks to develop.

How do you treat timber knots?

Treat the knot with a knotting solution – using a brush, apply a thin coat, proud of the surface. Once dry, apply a 2nd coat.

What is the strongest wood?

Australian BulokeAustralian Buloke – 5,060 IBF An ironwood tree that is native to Australia, this wood comes from a species of tree occurring across most of Eastern and Southern Australia. Known as the hardest wood in the world, this particular type has a Janka hardness of 5,060 lbf.

How do you stop wood from checking?

Coat the exposed end grain of the logs or boards with a thick layer of paint, varnish or a commercial green-wood sealer to prevent moisture from escaping too quickly. Wood loses moisture 10 to 15 times faster through the ends than it does through the faces.

What is a dead knot in timber?

A knot is where a branch was connected to the tree. There are two different types of knot, a live knot and a dead knot. A live knot is usually lighter in colour and will generally never fall out. A dead knot is darker and can fall out leaving a hole which can have an effect on the strength of timber.

What is the cause for twisting defects in timber?

Twist: Twist in timber rotates the ends of the timber in opposite directions. The main reason behind this defect is twisting of the trees by the strong wind. … The main reasons behind star shakes are extreme heat or frosting during the growth of the trees and rapid or uneven seasoning after cutting off the timber.

What are the natural defects in timber?

Defects in timber due to Natural ForcesWind cracks.Shakes.Twisted fibers.Upsets.Rind galls.Burls.Water stain.Chemical stain.More items…

What are the advantages of seasoning timber?

3 Advantages of Building with Seasoned WoodReduced Inception of Decay or Stain Fungi. Seasoned wood dried to a moisture content of less than 20% below the fibre saturation point will ultimately prevent the onset of stain fungi and decay. … Weighs Less. The weight of wood is reduced by about 35% or more when seasoned. … Increased Strength and Stability.

What types of wood have knots?

There are few knots in red and white oak, but a distinctive feature that makes it easy to identify the species is visible in a certain cut of the wood, called quartersawn, where it displays strong flecks of rays (cells that run perpendicular to growth rings).

What is the most reliable form of seasoning timber?

Natural Seasoning is the most traditional way of seasoning wood or timber. In this method wood is dried usually by the keeping the wood exposed to air, so that the moisture evaporates and wood is seasoned.

What are the three main types of timber?

These three types are: softwoods, hardwoods, and engineered wood. Each of these different wood types can be used in a number of different ways.