Step 3


Step 4


Contents


Caution: This points you to a safety precaution when you are performing a practical task.


Caution


When you are measuring, if your eye is not directly over the ruler, you can make a mistake. This is called an error or parallax. Small mistakes often add up in hard-line drawings.


Measure carefully on the lines to right and left, making small marks and drawing second and third height lines perpendicular to the baseline, about the same length. Measure and mark the correct height on the first height line you drew.


Step 3 Place the 30o side of a set square


sloping up to the right on the baseline, on the mark at the top of the height line and draw a line to the right. Place the 30o


sloping up to the left on the baseline, on the mark at the top of the height line and draw a line to the left.


Step 4 side of a set square


Activity: These are tasks where you apply concepts and knowledge you have learnt in the unit.


Using the same techniques, complete all lines, including the lines within the form.


Finish by erasing all line extensions and construction lines, and making hidden detail lines. Complete the drawing legend.


Activity 2 Practise using drawing instruments 1


Look at these drawings and, with a partner, decide what instruments you will need to make accurate drawings of each one.


2 On your own, make accurate isometric drawings of the shapes.


A: block in oblique sketch, 50 mm × 20 mm × 40 mm


B: single step 60 mm × 30 mm, each step height 15 mm


Practical Assessment Task Evaluation skills


By now you know that structures contain things, protect things, create an enclosed space, support things or provide a link across a span. You have looked at the forces on a structure and know the difference between structural members in compression and in tension. You also looked at ways of strengthening structures in order to reduce the risk of failure. Study the examples below and, in groups of three or four, discuss your answers to these questions.


PAT: A short practical assessment task that makes up the main formal assessment during each term.


Figure 1 Examples of complex structures Activity 1 Evaluate complex structures


1 Decide which of the two tables is the stronger and give reasons. 2


Identify any advantages or disadvantages of the table you have chosen.


3 Decide if the table needs to be strengthened in any way. 4 The loudspeaker on the stand could easily be knocked over. Give reasons why this statement is true.


5 Suggest three ways you could make it more stable. (10)


In this book you will also find: • exemplar tests at the end of each term, consisting of revision questions • a section on Tools for Technology at the end of the book, providing information on the basic tool and material requirements in the Technology classroom


• a glossed index, an alphabetical list of new words and definitions that can be used for revision, together with their page references.


Have confidence in your success with Oxford Successful Technology Grade 8! How to use this book 7


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38