Greetings EGD Grade 10s. I welcome you all to today's lesson. Today's lesson is about Drawing Scales. You will learn about the different scales used in drawings, how to convert different scales and how to apply your scale. In simple terms, a drawing scale is the ability to shrink or enlarge an object, to appropriately fit on a drawing page. I have posted a 2:02 video about today's topic which will enhance your understanding of Drawing Scales. Please watch the video provided below.

Task

"The best memories you can ever create for yourself, are those you spent thinking about the things you were thinking about." - Joshua Maponga

Task 1

Date: 06 September 2021 Total Mark: 20

Question 1: Scale Conversions (5)

- Refer to the Introduction video before attempting this one.

1.1 What is 40mm when converted to a scale of 1:1? (1)

1.2 What is 32mm when converted to a scale of 1:2? (1)

1.3 What is 16mm when converted to a scale of 2:1? (1)

1.4 If a drawing is drawn at a scale of 1:2, did it shrink or enlarge? (1)

1.5 What scale would you use if you had to enlarge a drawing 5 times (5x) its normal size? (1)

Question 2: Drawing Scale (15)

- Refer to the drawing provided below.

2.1 Redraw the object at a scale of 1:1. (Use appropriate drawing paper size) (5)

2.2 Redraw the object at a scale of 1:2. (Use appropriate drawing paper size) (5)

2.3 Redraw the object at a scale of 5:1. (Use appropriate drawing paper size) (5)

ALL THE BEST MY FAVOURITES!!!!! ("-") :)

Process

I will take you to the relevant processes you will need to take in to successfully complete your tasks. Remember my steps should not limit your thinking. You may approach the questions with your own understanding.

Question 1

- This question is a matter of bringing your mathematics knowledge into the EGD class as it is calculations.

- If you have 1 on one side and one on the other side it means that your objects are balancing as no side is more than the other. (1:1)

- If the left hand side is 2 and the right 1, it means that the left side is 2x more than the right. For every 1, you will multiply by 2. [ If the dimension is 10 and needs to be drawn to 2:1, it means that the 10 will be multiplied by 2, 10x2=20].

- If the left hand side is 1 and the right 2, it means that the right side is 2x less than the left. For every 1, you will divide by 2. [ If the dimension is 10 and needs to be drawn to 1:2, it means that the 10 will be divided by 2, 10/2=20].

- An enlarged drawing gets multiplied by the number in front of the colon.

- A reduced drawing is multiplied by the number behind the colon.

Question 2

- You may apply the normal drawing principles which I taught you in class.

- Apply the different scales as instructed by the question.

- The scale is applied to each dimension given.

- Be wary of conversions of diameters and radiuses.

- A diameter needs to be converted into a radius first before scaling (by dividing the given number by 2... D/2 = R).

- Question 1 forms the basis of Question 2. If you can convert the numbers on Question 1, then you will have no problem converting dimensions in Question 2.

Evaluation

QUESTION 1

MARK ALLOCATION

1.1

1

1.2

1

1.3

1

1.4

1

1.5

1

TOTAL

5

QUESTION 2

MARK ALOCATION

2.1, 2.2, 2.3

(5 x 3)

Drawing attempted

1

Correctness of the drawing

1

Line quality

1

Conversions correct

1

Semi-circles and circles drawn correctly

1

TOTAL

15

Conclusion

Learners, we have come to the end of our scales lesson. I hope i and the videos have been of great help. Remember that scales will not be covered in the exams as a topic but will be used and applied to the drawings that you will be doing in the next coming chapters up until your grade 12. You will have a Course Drawing on the topic to test your conversion skills. Remember it is better to root in the pillers now and not wait for tomorrow.

Quote of the day: "The greatest Estate that God has ever gifted you with is your Mind." - Steve Khompela