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Chapter 2

Design and Measurement Chapter 2 Design and Measurement

The Essentials of Design The art of creating real objects from imagined ideas is what design and measurement is all about. Whether you are designing and then creating a new line of clothing, jewellery, vehicles, entertainment centres, or backpacks, drawing and measuring play a key role. Being able to put your ideas down on paper and then adding dimensions so that you or others can construct them are powerful skills, and very helpful in today’s world.

Chapter Goals In this chapter, you will explore components of design and measurement. You will learn to draw objects from several perspectives, including oblique and exploded views. You will learn to use designs to estimate construction costs, including waste materials and taxes. You will create a design for a project and estimate its costs.

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Chapter Project The project for this chapter is to design and draw either an entertainment centre or a specialized backpack. You will then calculate the cost of materials required to construct your project. To complete this assignment you will work through project activities that break down the task into a series of steps. When you have completed the project, you will have added the following items to your project file: 1. A description of your project. 2. Drawings showing various views of the project. 3. A list of materials and their costs. 4. A plan for cutting the project materials that minimizes waste. 5. The cost of the completed project. Investigate different styles of entertainment centres or backpacks for your project.

Technology Much of today’s design work is done with the aid of computer-assisted design (CAD) technology.

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Exploration 1 One-point and Two-point Perspectives Consider the image shown below. You know that railway tracks are parallel and that they never get closer together. However, when you look at them, they appear to converge at a vanishing point. We can use this phenomenon to create projections of objects that make the objects appear three-dimensional. Using one and two vanishing points in drawings helps to create images that appear to have depth.

Goals

New Terms

The goal of this exploration is to create one-point and two-point perspective drawings.

vanishing point: the point at which parallel lines appear to converge.

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Look at the sugar cube in Example 1 below. To draw an object such as a sugar cube using a one-point perspective, use grid paper to draw the front of the object as it would appear facing you. Add a vanishing point at an appropriate distance to the right or left and up or down from the face of the drawing. Use dotted lines to connect the corners of the box to the vanishing point. Using the vanishing point lines, draw in a vertical line to represent the side of the box in the distance. Estimate the depth by eye to make it look natural. Use a horizontal line to show the top of the box in the distance. Shading the sides of the box can add to the sense of depth.

Example 1 Draw a 1-point perspective drawing of the sugar cube shown here.

Solution 1-Point Perspective: Right-handed

VP

VP

Hints Vanishing points can be left- or right-handed and above, below, or at the level of the front face. You may label left-handed vanishing points VPL and right-handed vanishing points VPR in your drawings.

1-Point Perspective: Left-handed

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A two-point perspective drawing uses two vanishing points to show an object viewed from a front edge or corner. See the solution below.

Example 2 Draw a 2-point perspective sketch of a sugar cube. Be sure to place both vanishing points on the same horizon line.

Solution 2-Point Perspective VPL

VPR

The following diagram shows a two-point perspective drawing of a snowmobile crate.

VPL

VPR

horizon line

New Terms

Technology

perspective: point of view.

Some drawing software enables threedimensional images to be created automatically from front views.

perspective drawing: a realistic view of an object that shows diminishing dimensions due to distance.

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Project Activity Choose your design project. You will design either an entertainment centre or a specialized backpack. Write a brief description of your design project parameters. Create a list of items that an entertainment centre could hold and estimate the minimum dimensions of the spaces needed to hold those items. Or list the items your backpack could hold—such as a laptop computer and accessories, or hiking gear. Determine the number of compartments in your backpack and estimate their dimensions. Investigate the types of materials that could be used to construct your project and determine their cost. Make a list of materials and their costs to add to your project file.

Career Connection

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Chapter 2 Design and Measurement

Notebook Assignment 1. Use grid paper to create one-point and two-point perspective drawings of each of the following objects. a)

b)

2. Draw a perspective drawing of the two high-rise buildings shown here.

Extension 3. Select an object of your choice—such as a piece of furniture in your classroom—and create perspective drawings showing significant detail. Use colour and shading to enhance your drawings.

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Exploration 2 Drawing a Box In this exploration, you will consider the shape that is the building block of many designs—the box. You will consider the shape’s use, how to price the materials used in building a box, and how to use the box shape efficiently. A building project often has components that can be put together in various shapes and sizes to become parts of the project. There are a variety of ways to draw simple box-shaped objects using various placements of the horizon line.

Boxes are the building blocks of many designs.

Goals In this exploration, you will consider the role of a common component of construction—the box—and draw boxes from various perspectives.

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Example 1 Draw a rough sketch of a box without a lid that could be used to hold a child’s shoes.

Solution Below is a rough sketch of a box. The dimensions of this box are 6 in  8 in  6 in. Because this is a rough sketch, no scale is used on the diagram.

6" 6" 8"

Example 2 Using two-point perspective, sketch the shoebox from: a) eye level b) a perspective where the horizon is above the object c) a perspective where the horizon is below the object

Mental Math

Technology

1. What is the volume of a box measuring 3"  3"  3”?

Many video and computer games have software that enables the viewer or player to move and see things in what appear to be three dimensions. Some house design programs are capable of the same thing.

2. What is the volume of a 10 cm  10 cm  10 cm box?

AutoCAD is a recommended resource and is the standard in many schools. Other resources include AutoSketch and 3D Home Architect.

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Solution a) from an eye-level perspective

VPL

VPR

6"

8"

6"

b) from a perspective where the horizon is above the object VPL

VPR

6" 8" c)

6"

from a perspective where the horizon is below the object

6" 8" VPL

6" VPR

Chapter 2 Design and Measurement

Project Activity 1. Now that you have selected for your project either an entertainment centre or a backpack, do part a) or part b), whichever applies. a) Create two sketches of the front of a backpack used to carry a laptop computer. Use any two views mentioned in this exploration. Show a significant amount of detail. b) Sketch one-point and two-point perspectives of a basic entertainment centre. The horizon may be above or below the image.

Notebook Assignment 1. The diagram to the right is of a hexagonal nut drawn in three dimensions. Sketch the nut using a one-point perspective where the horizon is above the object. 2. Consider a simple, roughly made coffee table for a ski or fishing cabin. It is made using plywood for the tabletop and two-by-fours for the legs. a) Draw the table from an eye-level perspective with two vanishing points. b) Describe possible situations where one might prefer an eye-level view to show an object. 3. As shown in the diagram, an overhead crane is lifting an object. The horizon is below the object. a) Draw the object using a two-point perspective. b) When might a perspective where the horizon is below the object be useful?

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Exploration 3 Exploded Views and Component Parts Three-dimensional objects, such as bookshelves or backpacks, can be drawn on two-dimensional paper by creating oblique views. Oblique views use lines drawn at angles to give a flat drawing a sense of depth, as well as showing measurements of depth. Exploded views of an object show the component parts in their relative position prior to final assembly, demonstrating the way the parts fit together. Figure A shows a wooden bookshelf drawn in oblique, or threedimensional form. This drawing can be exploded, so that the individual pieces of wood that Figure A make up the bookshelf can be clearly seen as separate items.

Goals

New Terms

In this exploration, you will focus on diagrams showing exploded views and constituent parts.

exploded view: a view showing how the components of an object fit together. oblique view: a slanted or inclined view of an object.

Chapter 2 Design and Measurement

Example 1—Exploded Views Draw an exploded view of the bookshelf in Figure A.

Solution Figure B

Note that in some cases, the thickness of the wood used for the bookshelf is not illustrated. Also note that the exploded view is a sketch, not a scale diagram, which means that the size of each piece of wood is about right. It does not have to be absolutely accurate or drawn to a specific scale.

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Diagrams that show constituent parts identify the individual pieces of materials that are being used (like the exploded view), but are sketched in two dimensions as a flat picture. These diagrams can be used to estimate the positioning of the pieces to minimize waste.

Example 2—Constituent Parts Draw the constituent parts of the bookshelf shown in Figure A.

Solution

Shelf ( 5)

Figure C

Side ( 2)

Backboard ( 1)

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n o i t c e n n o C r e e r a C

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Mental Math

New Terms

1. Find the area of a 4-foot by 8-foot sheet of plywood.

constituent parts: the parts of an object that fit together to complete the whole object.

2. How many 2-foot by 2-foot rectangles could be drawn on one sheet of plywood? 3. How many square metres are there in a piece of cloth measuring 2 metres by 6 metres?

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Notebook Assignment 1. The flower planter below was built using cedar boards. Create a constituent parts diagram.

2. The leather coin holder below was made by stitching two pieces of cut leather. Show the constituent parts. You may omit the stitching.

3. Below is a diagram of a desk organizer used to sort letters and other papers.

a) On graph paper, sketch an exploded view of this desk organizer. b) The bottom slots for letters are each 4" wide, 4" high, and 6" deep. The two sides of the desk organizer are each 8" high. Create a diagram of the constituent parts using a scale of 1:4. Diagrams should not consider the thickness of the wood.

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4. Examine the grocery bag shown below. a) Sketch an exploded view of the grocery bag. Think of the bag as a rectangular box. You do not need to include the handles in your sketch. b) Draw scale diagrams of the constituent parts. Label the parts and include dimensions. Handles may be omitted.

40 cm

30 cm

cm 20

Hints For a scale 1:4, one inch represents 4 inches or 1 cm represents 4 cm. To find the actual dimension of an object, multiply the dimension of the drawing by 4.

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Extension 5. Select an object from your classroom. a) Sketch the object as it appears in three dimensions. You do not need to sketch it to scale, but make sure the diagram looks right. b) Sketch an exploded view of the object. Drawing to scale is not necessary. You do not have to show the thickness of the pieces. c) Draw a diagram of the constituent parts using a scale of 1:4. A wooden chair is a rather complicated object to draw in exploded view.

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Exploration 4 Pictorial Drawings A pictorial drawing shows several faces of an object in a single view. Pictorial drawings show the appearance of objects. The perspective drawings you made earlier in this chapter are a common type of pictorial drawing. Other methods of drawing familiar objects include isometric drawings and oblique drawings.

Isometric Drawings To draw an isometric projection of an object, use isometric dot paper or isometric grid paper. All vertical lines on the diagram are drawn equal to actual lengths, or are scaled down using a specified scale factor. The object must be drawn from a corner. All lines that are not vertical are at 30° to the vertical.

Example 1 Draw an isometric sketch of a box.

Solution The diagram here shows an example of a box (16 cm  16 cm  24 cm), drawn on isometric dot paper.

16 cm 24 cm 16 cm

Goals In this exploration, you will focus on isometric and oblique drawings of objects.

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Oblique Drawings Oblique drawings are shown face on (that is, from directly in front of one face of the object). Oblique drawings can be drawn using square dot paper or square grid paper. There are two styles of oblique drawings, cavalier and cabinet.

Cavalier Drawings • • •

all dimensions are drawn to full scale receding lines are drawn at any convenient angle between 15° and 45°; often 45° is used a cavalier drawing will look distorted in shape

If an object is to be drawn as an oblique cavalier projection, the “front” surface of the object is shown fully and all sides are to the same scale. Other surfaces are inclined at a 45° angle to the front surface.

Cabinet Drawings • •

face is drawn to scale; the receding lines are drawn one-half scale this view removes some of the distortion, and a cube looks like a cube

Example 1 Draw the following: a) an oblique cavalier drawing of a box b) an oblique cabinet drawing of the same box c) an exploded view of the same box

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Solution a) There is more than one way to draw this oblique cavalier projection because you can choose which side will become the front. The diagram here uses the face that is 8"  5" as the front.

Top

5"

8" Side

5" Front

5" 8"

b) In an oblique cabinet view all receding lines are one-half scale. The diagram to the right is a cabinet projection of the box drawn in part a).

Top

Side Front c)

You may recall that if a box is to be drawn as an exploded diagram, the constituent parts are shown (in perspective) with some distance between them. The diagram should be drawn in such a way as to let the viewer see what the object would look like if all the pieces were pushed together to form the object. Exploded format pictures are rough but reasonable sketches of the object. (No specific scale is used.) Here is a picture of the box in exploded format.

Top 8" 5" 5" Side

5" 5"

Back

5" Front

5"

5"

Side

8" 8" 8" Bottom

5"

Hints Recall that oblique projections have the front surface of the object shown fully, while other surfaces are inclined at a 45° angle to the front surface. In a cavalier drawing, all dimensions are drawn true scale. Cabinet drawings give a better impression of depth and perspective, as well as a more realistic visual appearance. All lengths that are perpendicular to the front surface of the object are drawn at a 45° angle and are one-half scale.

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Essentials of Mathematics 12

Small Group Activity In this activity, you will work in a small group to create projection drawings of cubes. This will help you to draw more complicated objects later.

Materials • • •

4 cube-a-link blocks isometric dot paper grid dot paper

Instructions 1. Join the four blocks to create a shape. 2. Create a rough sketch of the four joined blocks in three dimensions. 3. Draw a projection of the four joined blocks using two-point perspective. 4. Draw an isometric projection of the four joined blocks using isometric dot paper. 5. Draw an oblique cabinet projection of the four joined blocks using grid paper.

Project Activity Create an exploded view of your design project. Roughly estimate the dimensions of the constituent pieces and then draw them.

Some backpacks have a compartment for carrying a laptop computer.

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Notebook Assignment 1. A set of stairs similar to the one shown is constructed off the back deck of a house in Prince Rupert. Prior to receiving a building permit, the architect must show a detailed drawing of the stairs. Create an oblique cabinet perspective. Use a scale of 1:8. Identify the scaled dimensions on your diagram if each of the two steps has a height of 8 inches, a depth of 12 inches, and a width of 40 inches.

8" 12"

40"

2. Consider the shoebox shown on the right. a) Sketch the shoebox as an isometric projection. Dimensions of the shoebox are 20 cm  30 cm  10 cm. b) Using a scale of 1:5, draw an oblique cavalier projection of the shoebox.

Extension 3. Draw an oblique cabinet projection of the shoebox in question 2.

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Games Map Colouring The map below shows several different countries. Each country is to be coloured so that the areas are easy to see. If two countries share a common border, then the two countries must be in different colours. A

B C

minimum of three colours needed

A

B

C

D

minimum of two colours needed A and D in one colour B and C in a second colour

Copy the map below and code it for colouring. Use the minimum number of colours.

The colouring of maps is a longstanding problem in mathematics. It was recognized long ago, and proven mathematically, that any map could be coloured with five colours. It was hypothesized that, in fact, only four colours are needed. No one was able to find or generate a map which required more than four colours, but at the same time it was not proven that such a map could not exist. Finally in the 1980s, a mathematician claimed to have proven that any map may be coloured with no more than four colours. Your teacher will supply you with copies of the diagram on the following page. See if you can colour it using only four colours.

Chapter 2 Design and Measurement

Games

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Exploration 5 Cost Estimates of Materials Before building any project, for example, the picnic table below, it is wise to consider the cost of the materials required to complete the project. To estimate the amount and cost of materials you will need, use the views of objects you draw as part of the design process.

Example 1 The picnic table below is made of wood. 36”

7’

12” 6”

Based on the diagram, the materials needed are: seats and table top

10 pieces of 2"  6"  7'

legs

4 pieces of 2"  6"  32" (approx)

cleats (for table top support)

2 pieces of 2"  4"  3' (max)

2 cleats for seats

2” x 4” x 6’

16 carriage bolts and nuts 16 washers 1 pound of nails

Goals In this exploration, you will estimate the costs of the materials needed for a project.

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Chapter 2 Design and Measurement

Wood of this size can be bought in 8-foot lengths. For the table, you would need to buy: 12 pieces of 2"  6"  8'

for the seats, table top, and legs

3 pieces of 2"  4"  8'

for the cleats

Cost of Materials A lumber store offers the following prices: one piece of 2" 6"  8'

$7.18

one piece of 2"  4"  8'

$4.75

carriage bolts and nuts

$0.52 each

washers (each)

$0.08

nails (per pound)

$2.52

If you need 1 pound of nails, 16 bolts and nuts, 16 washers, 12 pieces of 2"  6", and 3 pieces of 2"  4", what would the total cost be?

Solution

Guaranteed Prices Coast to Coast to Coast

Muskrat Lumber

MB

Materials lts and nuts Carriage bo Nails 8' 2"  6"  8' 2"  4"  Washers

 $8.32 16  $0.52 $2.52 1  $2.52   $86.16 12  $7.18 $14.24 3  $4.75  $1.28 16  0.08 = $112.53

Subtotal:

$7.88

GST 7%

(7%) $7.88

PST Total:

be added. charges will g in p ip sh *20%

s* Territorie

BC

$128.29

$8.32 $2.52 $86.16 $14.24 $1.28 $112.53 $7.88 4 (7.5%) $8.4 $128.85

$8.32 $2.52 $86.16 $14.24 $1.28 $112.53 $7.88 0 $120.41

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Project Activity Use previous estimates of your project’s constituent parts as a guide to determine the exact dimensions of the material needed. Show how material could be cut from sheets to minimize waste. Find the minimum amount of material required to complete your project.

Notebook Assignment 1. The diagram shows a single block for a quilt that your grandma made in the 1960s. The design is made from coloured rectangular strips of cloth. a) If she created a 70"  84" quilt, how many 14"  14" blocks were required? b) Lay out the red strips on 45" wide fabric in such a way as to minimize waste. Ignore seam allowances. What length of red fabric is required to construct the entire quilt? c) What did it cost your grandma to purchase red fabric for this quilt if the fabric cost $14.95 per yard? (Round the fabric length up to the nearest foot.)

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Extension 2. Below is a sketch of a desk organizer. Desk Organizer

Pencil holder

Note paper

Paper clips

Disks

CDs

The pieces of the desk organizer include: 1 piece back: 12"  4" 1 3 bottom: 11 ⁄2"  2 ⁄4" 1 piece sides: 3"  4" 2 pieces 3 dividers: 2 ⁄4"  3" 2 pieces 1 The desk organizer is made from ⁄4" plywood. Your task is to determine how many desk organizers can be created from one piece of 4'  4' plywood. Do not include wood for the pencil holder or the paper clip holder. Create a layout showing the constituent parts of the desk organizer on the 4'  4' plywood. To make your task easier, let the bottom be 12"  3" and the dividers 3"  3". Use the dimensions given above for the sides and the back. Assume no wastage for saw cuts.

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Exploration 6 Building from Scratch This chapter has emphasized the various skills leading up to the design and cost analysis of constructing an object. Following is a step-by-step guide to the design of a box and a cost analysis of building it.

6"

The Cost of Building a Box

8" 6" 5"

5"

5"

6"

1

⁄2" 8"

Suppose you were planning to build a closed box with the outside dimensions of 8"  6"  6". Could you estimate how much it would cost? If the box is to be made of standard spruce plywood and nails, the cost of producing one box can be determined using the following prices. standard spruce plywood (4 ft  8 ft  nails

—1— 2

in)

$17.77 per sheet $1.99/lb

Assume that to build the box, a minimum of one sheet of plywood and one pound of nails would need to be purchased, since those are the smallest quantities you can buy.

Goals In this exploration, you will focus on cost and waste reduction.

Chapter 2 Design and Measurement

cost of plywood cost of nails

101

$17.77 $1.99

Subtotal

$19.76

GST (7%)

$1.38

PST (7.5% in BC)

$1.48

TOTAL

$22.62

Constituent Parts Diagram If the box’s constituent parts are to be drawn, each part is drawn flat using a specified scale. Below is a picture of the box’s constituent parts using a scale of 1:4. Note that the box is constructed so that the sides sit on the bottom and the lid sits on top of the sides.

6"

( 2)

8"

( 2)

5"

5"

( 2)

8"

5"

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Example 1 a) How many boxes (8"  6"  6") can be made from one sheet of plywood? Assume no waste for saw cuts. b) How much plywood (total area) is wasted? c) What is the cost of the wasted plywood?

Solution

Figure A

a) To answer this you need to picture how to position the constituent parts of the box on the plywood to minimize the amount of plywood wasted and to maximize the number of boxes produced. A diagram helps. Looking at the constituent parts diagram on the previous page, you can see that each box requires two square pieces (5"  5"), two rectangular pieces (8"  6"), and two rectangular pieces (8"  5").

I" waste

8"

8"

8"

6"

6"

6"

6"

6"

6"

6"

6"

6"

waste

6" 6"

8"

6" 6"

8"

6"

8"

6"

55" to break into 5" strips 5"

8" 6"

8"

6"

Note that in each diagram there are 40 sections of each type of side, enough to make 20 boxes. 40"

8"

8"

Next, fit the constituent parts onto the plywood like puzzle pieces. When finished, the diagram could look like either Figure A or B shown here.

Figure B

8"

8"

6"

5" 5" 5" 5" 5"

6" 6" 6" 6" 5" 5" 5" 5" 5" 5" 5" 5" 8"

I" waste

8"

40 – 5"  5"

waste

40 – 6"  8"

36 – 8"  5" 30"

4 – 8"  5" 20"

continued on the next page

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103

b) To determine the amount of wasted wood, calculate the total area of the wood used, and subtract it from the total area of the plywood sheet. Area for the top and bottom: 8"  6"  40 pieces  1920 sq in Area for the front and back: 8"  5"  40 pieces  1600 sq in Area for the sides: 5"  5"  40 pieces  1000 sq in Total: 4520 sq in The plywood sheet is: 48"  96"  4608 sq in Therefore total waste is: 4608  4520  88 sq in c)

Cost of wood per square inch is: $17.77  4608  $0.0039/sq in Cost of waste wood is: 88 sq in  $0.0039/sq in  $0.34 or 34 cents

8" 6" 5"

6"

5"

5"

6"

1

⁄2" 8"

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Essentials of Mathematics 12

Project Activity Calculate the costs of creating your project using materials available to you. Comparison shop to determine the actual costs and explain your reasoning for the amount of materials needed. Make a price list similar to the one below showing the costs from two suppliers. For the backpack project, see the sample price list on page 108.

l der’s Speciaentre il u b e m o H mber ent C Muskrat Lu self Home Entertainm $26.98 each 50 Do-It-Your ine (4 ft  8 ft  1⁄2 in) package of $6.50 for a f melam one sheet o s wood screw rews ckets with sc 6 corner bra

$4.12 each

Muskrat Lumber Hints For home entertainment centre plans, use a search engine such as google.ca to search for woodworking plans. There are many web sites that offer free plans, including http://the3house.com/plans/menus/free_top_nav1.htm

Chapter 2 Design and Measurement

Notebook Assignment 1. Consider the birdhouse shown below.

The above diagram is drawn to a scale of 1:6. Draw the constituent parts. Estimate the actual dimensions of the birdhouse. Use the following information to help you. The birdhouse is constructed from 1⁄2 inch plywood. The bottom of the birdhouse fits within the sides and ends.

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2. Consider the drawing of the TV stand shown below.

a) Draw an exploded diagram of the TV stand. b) The drawing is an oblique cabinet perspective and the scale is 1:6. Find the number and actual dimensions of the constituent parts. c) You wish to build the TV stand from wood costing $89.95 for a 4'  8' sheet. Lay out the parts so as to minimize waste. d) If wood can only be purchased in full 4'  8' sheets for $89.95 or in half sheets (4'  4') for $49.95, what is the cost of the wood to make one TV stand?

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Chapter Review 1. Create a two-point perspective drawing of a dice showing the number six on one face. 2. Create both one-point and two-point perspective drawings for the object shown.

3. A pencil box is show below. Sketch an exploded view of the box.

4 cm

m 9c

20 cm

4. Create a constituent parts drawing of the box in question 3.

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5. Consider the backpack illustrated here. Find the total cost to make this backpack, using the information provided below. Note that the required quantities of materials are indicated.

Materials Cordura: 330 denier (4 oz per sq yd), black for the bottom and back. Ripstop Nylon: 70 denier (2.2 oz per sq yd), blue for the rest.

Quantity

Description

3

⁄4 yd 11⁄2 yd

Cordura (black)

$20.59 per yard (1⁄4 yd minimum)

Ripstop Nylon (blue)

$10.70 per yard (1⁄4 yd minimum)

3

120 yd Spool 100% Polyester Thread 1

⁄16" Elliptical Toggle

Cost (CAD)

$6.50 per 120 yard spool $0.81 each

1

1

4

3

$0.74 each

1

1" Side Release Buckle

$1.10 each

2 yd

1

$4.43 per yard

2 yd

1" Lightweight Nylon Webbing (black)

$2.43 per yard

2 yd

3 3

$0.29 per yard

2 yd

⁄4" Medium Weight Nylon Webbing (black) ⁄8" Elastic 1 ⁄2" Strapping

$1.32 per yard

1

1

14” Zipper

$3.45 each

⁄2 yd

⁄4" Ladderlocks ⁄8" Round Nylon Drawcord (black)

$0.37 per yard

Chapter 2 Design and Measurement

Project Presentation Your project presentation will be in the form of a poster, consisting of the following for either an entertainment centre or a backpack. Include: 1. A description of the type of material to be used and the unit cost of that material. 2. An exploded and constituent parts diagram of the project. 3. A diagram showing how the material could be cut to minimize waste when cutting out the constituent parts. 4. A cost estimate for the project.

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Case Study Lego blocks are among the most popular toys ever invented. They are also interesting from a design perspective. Choose a partner. Have one or both partners bring a set of Lego blocks to school. 1. What do you think are the important design elements of the various Lego blocks that have made them so popular? List and discuss these design elements. 2. Use graph paper to design a simple structure to be built using no more than six rectangular-shaped Lego blocks. Ask your partner to build the structure using only your diagrams.