Author: haroonkhan

Different kinds of defects are found in timber. Generally, they are caused by the nature of the soil on which the tree is grown, the fertility it gained during growth and changes occurred in the environment during its growth. The defects to be generally looked into while selecting timber for woodwork are discussed below. Knots…

Good timber should produce a clear ringing sound when struck. Decayed timber produces a dull and heavy sound.

The colour of quality timber should be uniform and of dark colour. Light-coloured wood usually indicates timber of low strength.

The timber should be easily workable, i.e., it should not clog the teeth of the saw. It should be capable of being easily planed. A good timber when planed shows a firm and bright appearance with a silky lustre.

Good timber should possess straight and close fibres, which signify uniformity in the timber.

Quality timber should be of heavy weight and uniform along the length under consideration.

It should be free from defects such as shakes, flaws, dead knots or blemishes of any kind.

Another important quality required for timber is it should to be durable. It should have a long life. It should be capable of resisting the actions of fungi, insects, chemicals, physical agencies and mechanical agencies during its lifespan.

This is the property of a material which returns to its original shape when the load causing the deformation is removed. Timber should possess this property, as it is essential when timber is used for bows, carriage shafts, etc.

It should possess a uniform structure. This is ensured when there is firm adhesion of fibres and compact medullary rays. Further, the annual rings should be regular and closely located.