Qualities of Good Timber

The following are the qualities of a good timber:

1. Appearance: A freshly cut surface of timber should exhibit a hard and shining appearance.
2. Colour: The colour of the timber should be preferably dark. A light colour indicates low strength.
3. Hardness: A good timber should be hard, i.e., it should offer resistance when it is being penetrated by another body. The chemical present in heartwood and the density of wood imparts hardness to timber.
4. Durability: A good timber should be durable. It should be capable of resisting the action of fungi, insects, chemicals, physical agencies and mechanical agencies.
5. Strength: A good timber should be strong for working as a structural member such as joist, beams and rafter. It should be capable of taking loads slowly or suddenly.
6. Structure: The structure should be uniform and the medullary rays should be hard and compact. The annual rings should be regular and should be closely located.
7. Mechanical wear: A good timber should not deteriorate easily due to mechanical wear or abrasion. This property is essential for places where timber would be subjected to traffic, like wooden floors and pavements.
8. Toughness: A good timber should be tough. It should be capable of offering resistance to shocks due to vibrations.
9. Elasticity: This is the property by which the timber returns to the original shape when load causing deformation is removed. This property is essential when timber is used for bows, carriage shaft, etc.
10. Fire resistance: Timber is a bad conductor of heat. A dense wood offers good resistance to fire and it requires sufficient heat to cause a flame.
11. Defects: A good timber should be free from serious defects such as dead knots, flaws and shakes.
12. Fibres: Timber should have straight fibres.
13. Shape: A good timber should be capable of retaining the shape during conversion or seasoning.
14. Smell: A good timber should have a sweet smell.
15. Sound: A good timber should give a clear ringing sound when struck.
16. Weight: A timber with heavy weight is considered to be sound and strong.
17. Working condition: Timber should be easily workable. It should not clog the teeth of saw and should be capable of being easily planed or made smooth.