Selecting high quality materials is an essential part of your job at Modern Edge. While we aim to purchase only quality materials you will often find defects. These can be either 'natural' or 'artificial'.

Natural defects: Present in a growing tree, such as growth defects, grain irregularity, shakes and knots.

Artificial defects: Caused by careless handling, incorrect conversion and seasoning techniques and inadequate protection of timber.

Follow this link if you'd like to see some pictures of types of timber defects.

Hints on selecting materials

When selecting material for drawer or door panels, the grain direction and final appearance are two factors that must be considered.

If defects are found in timber, a decision needs to be made to replace the piece or place the piece in an unseen position provided the strength of the unit is not compromised.

When selecting solid timber from stock for machining cutting list components, you need to consider several points:

• The appropriate width and thickness of each board should be selected to allow for the least amount of waste.
• Generally, the stock lengths for furniture timbers range from 1.8 metres to 4.2 metres long.
• When considering the width of boards, the variations can be extreme depending on the species of timber, availability and mill practices. Common widths are 75mm, 100mm, 150mm and 200mm.
• Boards are also cut to standard thickness. Common thicknesses are 25mm, 38mm, 50mm and 75mm.

Here's an activity for you to try:

Types of timber defects
Spring	A curvature along the edges of timber
Bow	A curvature along the faces of the timber
Cup	A curvature across the faces of timber. The effect is most common on back sawn boards.
Twist	A distortion across the faces which rotate the ends of the timber in opposite directions.
Cross shake	A fine, regular crack which extends across the face or edge or both face and edge.
Surface checks	Shallow cracks extending along the grain on the face or edge. Do not usually affect the strength of the timber but they do downgrade the appearance.
Gum pockets	Cracks in the timber which contain gum.
Gum veins	Gum deposits in veins or blotches on the surfaces of the timber. Structural strength is affected when gum deposit is loose and does not contain wood fibres.
Insect and termite holes	Termites, borers and insects make holes and tunnels in the timber which seriously affect its strength and appearance
Knots	Included sections of the branch in the timber. Dead knots The remains of damaged branches after drying out they become loose and fall out. Live knots They are sound and firm. If small, are not great defect.
Want and wane	The absence of wood from the edge of a piece of timber.

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