Year 10 Manufacturing (Resistant Materials)

Lesson 5 Week 5 (Clock Project)

Programmes of Study Teachers Rational Lesson1 (Situation and Brief) Practical Skills Design Skills Theory and Knowledge
Lesson 2
Orthographic Drawings
Lesson3
Brainstorming, Cognitive Charts
and Attribute Analysis
Lesson 4
Plastics. Properties, Uses and Common Forms.
Lesson5
Hardwoods and Softwoods Properties, Uses and Common Forms
Lesson6
Ferrous and Non-Ferrous Metals, Properties and Common forms
Lesson7
Drawing Styles and Modelling
Lesson8
Tools.

lesson 9
Flowcharts
Lesson10
vacuumforming
Lesson11
Quality
Lesson 12
Finishes



Hardwoods and Softwoods.


Hardwoods

Hardwoods are produced by broad leaved trees whose seeds are enclosed in fruit e.g. acorns. They have a variety of grains and a multitude of colours.


Evergreen hardwoods.

These are trees that keep their leaves all the year round. They generally grow quicker than deciduous trees and grow to a larger size. They are usually softer and easier to work than deciduous trees. There are only two European evergreens and these are holly and the laurel. Most evergreens are found in tropical or sub-tropical countries such as South America, central America, Africa, Burma, India and East and West Indies. Examples of Evergreen Hardwoods are:-
Mahogany, Teak, African Walnut, Iroko, Afrormosia, Ebony and Balsa.


Deciduous Hardwoods

These are the trees that lose their leaves in winter. They generally grow in temperate climates including the British Isles, Europe, Japan, New Zealand, Chile, and central U.S.A. Examples of Deciduous Hardwoods are:-
Oak, Ash, Elm, Beech, Birch, Walnut, Sycamore, Chestnut and Lime.

Softwoods

These are produced by the cone bearing trees (conifers). They are generally evergreen and have easily recognizable needle-like leaves. They grow in cold or cool temperate climates. These are countries such as Canada, Scandinavia and Northern Russia.
They grow much quicker than hardwoods and are cheaper, softer and easier to work. Their seeds are held in cones. common examples are:-
Pine, Fir, Spruce, Larch, Cedar and the Giant Redwood.


The terms softwoods and hardwoods are used to describe the leaves, seeds and structure of the trees. It is not used to describe the type of wood produced e.g. Balsa is light and very soft to use. It is used to make light weight models. It is however a hardwood. Yew is a coniferous tree but is heavy and hard to use like some hardwoods.



Examine the Common Hardwoods and softwoods Table.

The table displays a variety of common woods. It explains where and why each wood is used. It also explains the properties of woods and provides information on the advantages and disadvantages of using each one.

Using the above table answer the questions below.
.

1. Which type of hardwood would be suitable to make tough kitchen surface tops from? The surface would have to withstand shocks and wear.

2. If mahogany proves too expensive to use what would be an ideal substitute?

3. Give two examples of suitable hardwoods that may be used to make quality garden furniture?

4. A manufacturer of intends to create wooden sailing boats. Suggest a suitable hardwood?

5. Explain why European oak is not normally joined together with iron and steel fittings?

6. Name one property of Teak which makes it difficult but not impossible to use?

7. Why is Western Red Cedar a suitable material to use in the construction of children's playgrounds?

8. Name a softwood that is water resistant?

9. Explain what happens to Afrormosia if is placed in contact with iron in damp conditions?

10. Name a hardwood which is both elastic and strong. This type of hardwood is also durable and does not split easily?


Lesson Task :

To be able to appreciate the great variety of hardwoods and softwoods commonly used in society.
To be able to answer questions regarding the properties, uses and common forms of woods.

Programmes of study

5b How materials can be combined and processed to create more useful properties, and how these properties are utilised in industrial contexts;







s;