Question 1
(a) (i) Name the two groups into which wood is classified.
(ii) List three factors used in classifying wood.
(b) List appearance properties of wood.
(c) Illustrate with a sketch how sawn boards are arranged for air seasoning.
(d) (i) State two effects on twist defect on timber.
(ii) Illustrate with a sketch of twist defect on a timber.
Observation
Majority of the candidates scored very good marks on the classification of wood but scored low in other questions and required sketches. The expected responses to the area where candidates performed below expectations are in the following.
- (ii) Factors used in classifying woods
- Type of leaves
- Type of seed
- Type of pores
- Location of trees
(b) Appearance properties of wood
- Colour
- Gloss
- Texture
- Macrostructure/grain
- Figure
(c) Sketch of how sawn boards are arranged for air seasoning
(d) (i) The effects of twist defect on timber
- It degrades timber;
- It lowers its value.
- It distort the length of the timber
- It makes it difficult to work on it
(ii) Illustration of a twist defect on timber