technical drawing y1

Unit of Competency: Prepare Freehand Drawing

Module No.: 1 Module Title: Preparing freehand Drawing

Republic of the Philippines

Department of the Education PUBLIC TECHNICAL-VOCATIONAL

HIGH SCHOOLS

ACKNOWLEDGMENT

Copyright Department of Education 2008 First Published JUNE 2008

This draft was prepared during the Competency-Based Learning Materials Development Workshop conducted at the Marikina Hotel,

Marikina City on February 18-22, 2008 and Development Academy of the Philippines (DAP) on May 5-10, 2008.

This learning instrument was developed by the following personnel:

Technology Teachers:

Mario S. Gregorio, Ed.D. Tagum National Trade School

Tagum City, Davao del Norte, Region XI Roy S. Luneta

Bauan Technical High School Bauan, Batangas

Ariel F. Maglalang

Assemblywoman Felicita G. Bernardino Memorial Trade School, Lias, Marilao, Bulacan, Region III

Juanito Bugaoisan Don Alejandro Roces, Sr. Science and Technology

San Fernando, La Union Arlene V. Tobias

Mabalacat Technical High School Mabalacat, Pampanga

Facilitator:

Aida T. Galura Angeles City National Trade School Sunset Valley, Angeles City

Encoders:

Mel Contapay Office of Legal Affairs

Department of Education Meralco Ave., Pasig City

Maria Riza Zamora DepED Budget Division Meralco Ave., Pasig City

The Refinement And Enrichment Of The Competency-Based

Curriculum and Competency-Based Learning Materials was done in Marikina Hotel, Marikina City on April 13-18, 2009 through the concerted effort of the following writers:


Mario S. Gregorio Ed. D. Tagum National Trade School

Tagum City, Davao del Norte, Region 11 Condrado C. Casulla

Pangasinan School of Arts and Trades Lingayen, Pangasinan, Region 01

Nelson M. Arisga Malvar National High School

Malvar, Batangas, Region 4A Alexander M. Latoga

Manuel S. Enverga Memorial College of Arts and Trades Mauban, Quezon, Region 4A

Mirasol F. Dasig San Pedro Relocation Center National High School

San Pedro, Laguna Region 4A

Contextual Writer:

Marvin R. Viernes Muntinlupa Business High School Muntinlupa City, NCR

Encoder:

Lawrence D. Cruz DepEd EID-TS

DepEd Complex Meralco Ave. Quezon City

Jeffree O. Ponce DepEd EID-TS DepEd Complex Meralco Ave.

Quezon City

Facilitator: Orlando E. Manuel PhD

Principal Cabarroguis National School of Arts and Trades

Cabarroguis, Quirino Region 02

This work was funded by the Department of Education.

REFERENCES AND FURTHER READING

Giesecke, Mitchell, and Spencer. Technical Drawing; The Macmillan

Company: 1949.

French and Vierck. Engineering Drawing; MacGraw, Hill Book Company,10th

editon: 1960

German M. Manaois. Drafting 1 and 2; Phoenix Publishing:1983

Norman Stirling. Introduction to Technical Drawing; Delmar Publishing: 1977

TABLE OF CONTENTS

Perform Different Lettering Styles &Techniques

Page

How to Use this Module ……………………………………………….. I Introduction ……………………………………………….. ii Technical Terms …………………………………………………………. iii Learning Outcome 1- Perform Different Lettering Styles &Techniques ……………………………………………………..

1

Learning Experiences/Activities …………………………………. 2

Information Sheet 1.1 …………………………………………… 3 Self – Check 1.1 ……………………………………………………… 10 Learning Outcome 2 – Sketch Simple Objects ……………………… 12 Learning Experiences/Activities ………………………………….. 13 Information Sheet 2.1 ……………………………………………… 14 Self Check 2.1 ………………………………………………………… 17 Learning Outcome 3 – Perform Freehand Sketches ………………… 18 Learning Experiences/Activities …………………………………….. 19 Information Sheet 3.1 ……………………………………………… 20 Self – Check 3.1 ……………………………………………… 30 Operation Sheet 3.1 ……………………………………………… 33 Self – Check 3.2 ……………………………………………… 35 Assessment Resources …………………………………………………..

Answer Key ……………………………………………… 36

38-41

HOW TO USE THIS MODULE

Activities are properly arranged in this module to help you work on

your own pace. This module also covers the knowledge, skills, and desirable

attitude you need in technical drawing.

A Pre-assessment precedes the learning activities in each module to

determine your learning level and need.

The Learning Activity Page gives the sequence of the learning task.

This page serves as the road map in achieving the desired objectives.

When you are able to accomplish all the tasks required, a post-

assessment is given to check if the student is already competent with the

specified learning outcome/s and ready for the next task.

Definitions of terms are provided in this module for your better understanding.

Program/Course : TECHNICAL DRAWING I

Unit of Competency : PREPARE FREEHAND DRAWING

Module Title : Preparing Freehand Drawing

INTRODUCTION People around the world speak with different languages but they come

up with common understanding on drawing. That’s the reason why drawing

becomes a universal language.

This module is intended to provide a thorough coverage of technical

drawing for use as a classroom text and/or as a reference manual.

Performing freehand sketches, sketching simple object: and perform different

lettering styles and techniques are discussed in the module. Equipped with

all the concepts, the student can then competently transmit the ideas

through a drawing.

SUMMARY OF LEARNING OUTCOMES

Upon the completion of this module, you will be able to:

LO1 Perform different lettering styles and techniques.

LO2 Sketch simple objects.

LO3 Perform sketches.

TECHNICAL TERMS

Accented is a form of heavy and light elements of letters.

Slant line is an inclined line.

Style is the manner of designing or shaping a drawing.

Sketching is a preliminary drafting.

Stroke is the technique of printing letters.

Uppercase Letters are the big letters of the alphabets.

Proportion refers to the quality standard of shape, figure, form of object or

drawing.

Freehand Drawing. is performed without the use of mechanical drawing

instruments. it is purely done by pencil rendering.

1




Learning Outcome 1 : Perform different lettering styles and techniques

Assessment Criteria

1. Importance of lettering is properly explained

2. Each style of letter is performed on commercial standards.

3. Care and maintenance of lettering instruments are properly observed

and practiced.

4. Appropriate lettering instruments are correctly used.

5. Decorative letter styles are creatively done for a particular purpose.

References:

1. Giesecke, Mitchell, and Spencer. Technical Drawing; The Macmillan

Company: 1949.

2. French and Vierck. Engineering Drawing; MacGraw, Hill Book

Company,10th editon: 1960

3. German M. Manaois. Drafting 1 and 2; Phoenix Publishing:1983

4. Norman Stirling. Introduction to Technical Drawing; Delmar Publishing:

1977

2

LEARNING EXPERIENCES/ACTIVITIES

Learning Outcome # 1: Perform different lettering styles and

techniques

Learning Activities Special Instruction

1. Read information sheet no. 1

2. Answer self check no. 1.1 to

test your knowledge about

lettering.

3. Review the information sheet if

some items were not properly

carried out.

Try to answer the self check.

3

INFORMATION SHEET # 1.1

Skill in lettering is a basic requirement for a student in drawing. He

must be exposed to the lettering activities to orient him on the quality

standard in printing letters.

Lettering is used as a form of communication. As applied in drawing,

it adds beauty if it is well-printed. Likewise, it can destroy the appearance of

the drawing once it is not done well.

The Four Group of Letters

1. Gothic Letters. They are the most simple and readable among the

four group of letters. It has a uniform stem. It should be applied

only for poster and advertisement purposes.

Aa Bb Cc Dd Ee Ff Gg Hh Ii Jj Kk Ll Mm Nn Oo Pp Qq Rr Ss Tt Uu Vv Ww Xx Yy

Two forms of gothic letters:

a. Commercial Gothic. It is printed with heavy stem. It is used

for advertisement purposes only.

b. Single Stroke. It is printed with thin stem. It is used for

engineering drawing purposes.

2. Roman Letters. The thickness of these letters is not uniform. they

have pointed stem which is called “serif”. They must be used for

books, magazine, newspapers, and text matters.

Aa Bb Cc Dd Ee Ff Gg Hh Ii Jj Kk Ll Mm Nn Oo Pp

Qq Rr Ss Tt Uu Vv Ww Xx Yy

4

The Three Classics of Roman Letters:

a. Old Roman Letters. They are printed by means of layout

form using the flexible lettering pen. The thickness of the

thin stem must be ½ from the thickness of the heavy

stem.

b. Modern Roman Letters. They are printed in single stroke

using the speedball pen.

c. Modified Roman. Similar to Modern Roman, they are

printed in single stroke using the speedball pen.

However, this style must be printed in the absence of

serif.

3. Spanish Script. It is considered as artistic letters. It is purposely

used for certificates, diplomas, citations, greetings and invitation

cards.

4. Text or Old English. This style is the most artistic among the four

groups of letter. Similar to Spanish script, it is also used for

certificates, diplomas, citations, greetings and invitation cards.

5

The Rule of Stability of letters

This refers to the standard rules to be considered in printing the

letters particularly on the following:

1. Upper Case letters. They are letters which are printed in capital form.

Three guidelines are cap line, waist line, and base line.

Example:

2. Lower Case Letters. These are the letters which are printed in small

letters printed with the use of four guidelines such as cap line, waist line,

base line, and dropped line.

Example:

The General Proportion of Letters

1. Compressed or Condensed. This particular proportion should be

applied only when the space is limited. The letters are printed with

closer distance and its width is narrower than the normal size.

Example:

COMPRESSED

A B C D E F G

cap line

waist line

base line

a b c d f g y

cap line

waist line

dropped line

base line

6

2. Extended. This proportion is applied when there is a more space. The

width of the letter is wider than the height.

Example:

3. Normal. This proportion is applied when there is normal space. The

letter is printed in the normal size.

Example:

NORMAL

The Two Proportion of Thickness

1. Boldface. This refers to the letters which are printed with heavy stem.

Example:

BOLDFACE

2. Lightface. This refers to the letters which are printed with thin stem.

Example:

7

Below are the suggested lettering tools and instruments and their uses: 1. Speed Ball - used in writing different various styles of

letters

2. Lettering Brush - used for sign painting 3. Felt Point Pen - used for sign painting 4. Letter Template - used as guide for letter transfer

5. Letter Transfer - used to direct letter transfer 6. Pencil - used for lettering and sketching 7. Technical Pen - used for Gothic letters 8. Leroy Lettering Pen - used for engineering and architectural

lettering

Order of Strokes in Lettering

The first letters that should be studied are I, L, T, F, E, H. These letters

are the easiest to draw because the basic strokes are vertical and horizontal.

You should practice making these letters according to the models.

The next group P, R, B, U and J requires close study because of the

introduction of the curved line aside from the three already given.

The last group of letters is C, G, O, Q, D and S which are based on the

circle.

The M and W must be printed wider than the other letters. It is

suggested therefore that its width should be greater than the other letters by

25 percent. The letter I is the thinnest letter.

8

Making Numerals

All mechanical drawings involve the use of numerals, hence, they

should be studied closely. Notice that in the figures below are all 6 units and

5 units wide except 1. All figures are composed of the essential strokes

found in the letters which are straight and curved. See Figure 1.1

Single stroke vertical upper case letters and numerals Figure 1.1

9

Single stroke vertical lower case letters Figure 1.2

Single stroke inclined upper case lower case letters and numerals Figure 1.3

10

Single stroke inclined lower case letters Figure 1.4

11

SELF CHECK 1.1

LO1. Perform different letter styles and techniques

I. Multiple Choice. On the space provided before each item, write the

letter of the word or group of words that will make the statement

complete and correct.

________ 1. Which of the styles of letter is applicable for engineering

drawing?

a. Single stroke gothic letters

b. Commercial gothic letters

c. Modified roman letters

d. Modern roman letters

________ 2. This proportion of letters is only used when the space is

enough.

a. compressed

b. extended

c. normal

d. lightface

________ 3. Among the letters below, identify which of them has widest

width?

a. N and O

b. M and W

c. C and X

d. H and L

________ 4. Which of the statements below clearly define the meaning

of rule of stability?

a. This refers to the standard rules to be considered in printing

the letters

b. This refers to the styles and methods of printing the letters.

c. This refers to the three forms of proportion of letters.

d. It is a standard guideline to be observed in using the

different lettering tools.

12

________ 5. Which of the proportion of letters below is applicable for

limited space?

a. compressed proportion

b. extended proportion

c. normal proportion

d. boldface proportion

II. Answer the following questions briefly:

1. Discuss the effect of the lettering on the drawing when it is not

properly printed.

2. How important is lettering in the drawing?

III. Direction : Illustrate the selected letters below in the form of

Gothic,

and Roman letters.

A, B, K, M, R, X, and Y

13




LO2. Sketch simple objects

Assessment Criteria

1. Principle of sketching objects is properly discussed.

2. Different shapes of objects are correctly identified.

3. All principles of proportion in sketching simple objects based on

commercial standards are explained.

4. Procedure in sketching is correctly followed.

References:


Company: 1949.





1977

14


Learning Outcome # 2: Sketch Simple Object



3. Answer self check no. 2.1 for

better understanding.


Try to follow the procedure

correctly.

15

INFORMATION SHEET 2.1

Sketching is a basic skill to be learned by the student before he will

be exposed to higher level of drawing activities.

Sketching is a preliminary layout or draft before making it into final

drawing. This can be done in a light line forms with the use of sketching

tools and materials.

Principles of Sketching Objects

Before doing sketching activities, it is important to know the basic

principles in sketching. The following are:

Analyze the proportions of the subject.

Mentally picture out the basic shape of subject.

Determine the small details on the subject.

Establish height and width of the subject to be sketched.

Use the appropriate sketching materials.

The Two Basic Proportions of Object

Height. It is the distance elevation from bottom to top. Height must

be proportioned to the width of the subject.

Width. It is the distance from front to rear. Likewise, it should be

proportioned to the height of the subject.

16

Basic Shapes of Objects

1. Rectangle - has its opposite sides equal and all its angles are

right angles.

2. Square - has four equal sides and angles

3. Hexagon – is a polygon having six equal sides

17

4. Rhombus- is a quadrilateral with four equal sides and angles

which may not be right angles but are also equal.

5. Deltoid- is a quadrilateral with pairs of equal sides.

6. Scalene Triangle- is a triangle whose two sides and two angles are

equal.

7. Equilateral Triangle- is a triangle with all sides and angles are

equal.

18

8. Circle. A figure which has an angle of 360 degrees.

9. Oblong. An elliptical figure which shapes originates from the

circle.

19

SELF CHECK 2.1

LO2. Sketch simple object

Direction : A. Identify the terms referred in the following.

____________________1.The most important role in freehand sketching.

____________________2.A polygon with six equal sides.

_____________________3. A quadrilateral with four equal sides and four equal

right angles.

____________________4. A quadrilateral which opposite sides are equal and

whose angles are also right angles.

____________________5. A quadrilateral with two opposite side parallel.

____________________6. A triangle where all sides and angles are equal.

___________________ 7. A quadrilateral with pairs of sides are equal.

B. Enumerate what are being asked.

8-10 Give the three basic shapes of an object.

20




Learning outcome 3: Perform freehand sketches

Assessment Criteria

1. Drawing pencils are selected based on specific job requirements.

2. Proper care and manipulation of drawing tools, materials and

equipment are observed and practiced.

3. Techniques on line exercises are demonstrated according to standard

procedure.

4. Shading techniques are applied making use of appropriate standard

specification.

5. Pencil rendering techniques are applied according to appropriate

drawing materials.

6. Creativity on value scale in shading is applied.

References:


Company: 1949.





1977

21

LEARNING ACTIVITIES/ EXPERIENCES

Learning Outcome # 3: Perform Sketches


1. Read information sheet no. 3.

2. Answer self check no. 3.1 to

test your understanding.

3. If not able to answer all items

correctly, review again the

information no. 3

4. Read operation sheet no. 3.1

Observe carefully the

teacher’s demonstration

5. Read operation sheet no. 3.2,

analyze the given procedure.

6. Perform self check no. 3.2 to

test your knowledge on

freehand sketches.


Ask the teacher when some

items are difficult to

understand.

Ask your teacher for some

clarifications.

22

INFORMATION SHEET 3.1

LO3. Perform freehand drawing

Drawing Principles Freehand and Sketching

Freehand sketches are of great assistance to the designers in

organizing their thought and recording their ideas. They are effective and

economical means of formulating various solutions to a given problem so

that a choice can be made between them at the outset. Often, much time

can be made between them at the outset. Much time can be lost if the

designer starts his scaled layout before adequate preliminary study with the

aid of sketches. Information concerning changes design, covering

replacement of broken parts or lost drawing, is usually conveyed through

sketches.

Drawing Tools, Equipment, and Materials

1. Drawing Paper- is manufactured in four colors, namely: white, cream,

light green and buff. It comes in different sizes of

various sheet thickness.

2. Ruler- is used for marking out distances as well as for measuring

purposes.

3. Pencil- is manufactured in various grades of hardness ranging from 7H

which is very soft up to 9H. The lead of pencil is a

mixture graphite, clay and wax. The clay makes the lead

hard. The harder the pencil is, the lighter the line is

produced.

23

4. Drawing Table– may refer to any ordinary table found in a school shop or

in the home with convenient height that will make you comfortable while

working. Its main purpose is to provide you a place where you can fasten

your paper.

5. Drawing Board- is necessary if no drawing bench is available. The

common size of drawing board is 45.71 cm X 61 cm.

6. T-square- is an instrument used for drawing horizontal lines. It also

supports the triangle for vertical or sloping line drawing.

24

7. Triangle- is used to draw both vertical and oblique lines. It is the 45-

degree triangle and the 30-60-degree triangle.

8. Drawing Tape-is used before any drawing activity is to be started.

the drawing paper has to be fastened on the drawing

board. The acceptable method of fastening is with the

use of tape.

9. Eraser – has two kinds: the red rubber and the yellow art gum.

of the two kinds of eraser the yellow art gum is better to

use for it correct errors easily and removes unwanted lines.

25

10. Protractor- is used to lay out angles. It is made of transparent plastic

and a half circle shape. It has two scales: the outside

scale which is from zero to 180 degrees going to the left

and the inside scale which is the opposite.

11. Compass- is an instrument for drawing arcs and circles. The common

kinds of compass are the pencil compass and the drawing

compass. The pencil compass has an opening for the

pencil while the drawing compass has a piece of lead fitted

intone of its leg.

26

12. French curve – is an instrument for drawing irregular curves other than

arcs and circles.

12. Ruling Pen – is an instrument for inking drawings. It is adjustable in

order to produce thickness and thickness of lines.

27

14. Divider- is used for dividing lines or distances into equal parts.

15. Scale- is used for measuring and for scaling process.

Proper Care and Maintenance of Drawing Tools and Instruments

1. Keep your instruments and equipment clean.

2. Wipe the pencil point with a piece of cotton and not your finger.

keep your drawing tools and instruments in proper places before and

after using.

28

Basic consideration in freehand sketches

It is necessary to expose the learner in the different line exercises as

basic activities in freehand sketches. The following are the forms of lines:

1. Horizontal line. It is a line parallel to the horizon or a line that form 180

deg. It is drawn from left to right.

2. Vertical line. Is a line that can be obtained by suspending plumb and

this line form 90 degrees from the horizontal line. It is drawn from top to

bottom.

3. Inclined line. It is neither horizontal nor vertical line.

4. Curve line. A line produced by a circular movement.

29

Importance of Shading in freehand drawing and sketches

Shading is the process of making the visible surfaces of an object. It is

applied in a variety of tones or values.

The following are the tones or values of shading:

1. Light Values. This represents the surface which receives the

greatest amount of light.

2. The Medium Values. This represents the surface which receives

less amount of light.

3. Dark Values. This represents the surface very little amount of

light.

In shading application, the source of light is assumed to be coming

from the upper left-hand corner of the drawing paper and rays of light are

imagined to be inclining at an angle of 45 degrees.

Techniques in Shading Application

1. Apply the lightest shading on the part of a surface which receives

more light.

2. Shade the portion of a surface which receives less light with medium

values.

3. Shade the portion of a surface which receives little amount of light

with a heavy shade.

30

Methods of shading application

1. Line shading. A technique of showing the various shades of an object

by using lines.

2. Stippling. It is applied by dabbing the pencil point or pen to produce

dots on the surface of the object.

31

3. Mixed shading. It is called mixed because it applies both the line and

dotted shading. However, the lines and dotted

shading must not be applied to the same surface of

the object.

4. Continuous Tone Shading or Smudge Shading. This is applied by

using the powdered graphite or lead of a pencil.

Note:

Refer to Operation Sheet No. 3.2 and Self Check No. 3.2 for the

application of this activity.

32

SELF CHECK 3.1

LO3. Perform freehand sketches

Direction: A. Identification: Write the correct answer in each blank.

____________________1. An instrument used for drawing horizontal lines. It

also supports the triangle for vertical and sloping line

drawing.

____________________2. It is an ordinary table found in a school shop or in

the home with a convenient height that will make you

comfortable while drawing.

____________________3. An instrument used for marking out distances as

well as measuring purposes.

____________________4. An instrument used for drawing irregular curves

other than arc s and circles.

____________________5. An instrument used for dividing lines or distances

into equal parts.

____________________6. A tool used to draw both vertical and oblique lines

B. Enumeration:

7-10 Four colors of drawing papers

33

OPERATION SHEET 3.1

LO3. Perform freehand sketches

Skill in line exercises is a basic requirement prior to exposing

the learner to higher drawing activities considering that all forms of

drawing emanates from a line, it might be horizontal, vertical,

inclined, and curve lines.

Procedures in sketching horizontal, vertical, inclined, and curve lines

1. Sketch a rectangle at 120 mm x 160 mm.

2. Divide the rectangle into four equal parts.

3. Sketch horizontal lines on the first part of the rectangle, start

at the left going to the right. (Each line must have 5mm gap

distance).

4. Sketch vertical lines on the second part of the rectangle.

Start at the top down to the bottom. (Each line must have

5mm gap distance).

5. Sketch inclined lines on the third part of the rectangle with a

downward stroke. (Each line must have 5mm gap distance).

6. Sketch curve lines from left to right. (Each line must have

5mm gap distance).

(See figure 3.5)

34

Figure 3.5

35

OPERATION SHEET 3.2

LO3. Perform freehand drawing

Freehand drawing is executed without the use of mechanical

drawing instruments. It is purely done by means of sketching.

Procedure in making freehand drawing:

1. Prepare the model/object.

2. Imagine the basic shape from which the model originates and

sketch on the appropriate drawing paper.

36

3. Analyze the proportion and sketch the temporary line ( width).

4. Complete the freehand drawing activity.

5. Darken the final edges and erase the sketching lines.

6. Apply line shading.

WIDTH

37

SELF CHECK 3.2

DIRECTION: Sketch the given model below and apply continuous

tone shading.

38

ASSESSMENT RESOURCES

Performance Assessment

Scoring Rubrics

Criteria Score (Tick the corresponding pts.)

Accuracy

50

45

40

Speed

10

6

8

Neatness

25

20

15

Lettering/Labeling

15

12

10

8

Total

Performance Criteria: Accuracy

50 pts - The output is accurately done.

45 pts - Two to five errors are observed on the output.

40 pts. - Six to ten errors are observed on the output.

Speed

10 pts - The output is done 5 minutes before the time.

8 pts - The output is done on time.

6 pts. - The output is done after the allotted time.

Neatness

25 pts. - No errors made on the output.

20 pts - Two to three erasures made on the output.

15 pts - Four or more erasures made on the output.

39

Lettering/Labeling

15 pts. - All information must be completely indicated and legibly

printed.

10 pts. - Aieces of information are legibly printed but some are

missing.

40

ANSWER KEY 1.1

TEST I.

1. a

2. c.

3. b

4. a

5. a

TEST II. ( Teacher’s check)

TEST III. ( Teacher’s check)

41

ANSWER KEY 2.1

1. Proportion

2. Hexagon

3. Rectangle

4. Square

5. Trapezoid

6. Equilateral triangle

7. Rhombus

8. Rectangle

9. Hexagon

10. Square

42

ANSWER KEY # 3.1

1. T-square

2. Drawing table

3. Scale

4. French curve

5. Divider

6. Triangle

7. White

8. Cream

9. Light and green

10. Buff

43

ANSWER KEY # 3.2

(Teacher’s Check)

ANSWER KEY 3.1

a. Octahedron

b. Tetrahedron

c. Hexahedron

d. Icosahedron

e. Dodecahedron

Unit of Competency: Construct Geometrical Figures

Module No.: 2 Module Title: Constructing Geometrical Figures



HIGH SCHOOLS

ACKNOWLEDGMENT

Copyright Department of Education 2008

First Published JUNE 2008

This draft was prepared during the Competency-Based Learning Materials Development Workshop conducted at the Marikina Hotel, Marikina City on February 18-22, 2008 and Development Academy of

the Philippines (DAP) on May 5-10, 2008.

This learning instrument was developed by the following

personnel:

Technology Teachers: Mario S. Gregorio, Ed.D.

Tagum National Trade School Tagum City, Davao del Norte, Region XI

Roy S. Luneta Bauan Technical High School

Bauan, Batangas

Ariel F. Maglalang Assemblywoman Felicita G. Bernardino Memorial Trade School, Lias, Marilao, Bulacan, Region III

Juanito Bugaoisan

Don Alejandro Roces, Sr. Science and Technology San Fernando, La Union

Arlene V. Tobias Mabalacat Technical High School

Mabalacat, Pampanga Facilitator:

Aida T. Galura Angeles City National Trade School

Sunset Valley, Angeles City

Encoders:







Mario S. Gregorio Ed. D. Tagum National Trade School

Tagum City, Davao del Norte, Region 11 Condrado C. Casulla


Nelson M. Arisga Malvar National High School

Malvar, Batangas, Region 4A Alexander M. Latoga




Contextual Writer:

Marvin R. Viernes Muntinlupa Business High School Muntinlupa City, NCR

Encoder:




Quezon City

Facilitator: Orlando E. Manuel PhD

Principal Cabarroguis National School of Arts and Trades

Cabarroguis, Quirino Region 02




Company: 1949.


editon: 1960


Norman Stirling. Introduction to Technical Drawing; Delmar Publishing:

1977

TABLE OF CONTENTS Page

How to Use this Module ……………………………………………….. I Introduction ……………………………………………….. ii Technical Terms …………………………………………………………. Iii

Learning Outcome 1 – Bisect Lines, Arcs, Circles & Angles ……….. 1


Information Sheet 1.1 …………………………………………… 3

Operation sheet 1.1 ……………………………………………….. 5

Self- Check Sheet 1.1 …………………………………………………… Self – Check 1.2 ……………………………………………………..

11 13

Learning Outcome 2 – Draw Regular Polygons ……………………… 15

Learning Experiences/Activities ………………………………….. 16

Information Sheet 2.1 ……………………………………………… 17

Operation Sheet 2.1 ……………………………………………… 18

Self Check 2.1 ………………………………………………………… 23

Learning Outcome 3 – Draw Regular Solids …………………………. 24

Learning Experiences/Activities …………………………………….. 25

Information Sheet 3.1 ………………………………………………. 26

Self – Check 3.2 ……………………………………………… 29

Assessment Resources ………………………………………………….. 30

Answer Key …………………………………………………………………. 32-35


Unit of Competency : CONSTRUCT GEOMETRICAL FIGURE

Module Title : Constructing Geometrical Figures

INTRODUCTION This module is designed for the student to familiarize with geometrical

figures and plane geometry and to be able to draw mechanically using

compass, triangle, dividers, pencils and erasers. The basic knowledge in

geometric construction which will be integrated or applied in any area of

specialization are discussed in this module.

Accuracy, proper practice in holding different materials and

instruments and safety measures are also included in this module.



LO1 Bisect lines, arcs, circles, and angles

LO2 Draw regular polygons

LO3 Draw regular solids

TECHNICAL TERMS

Bisect- means to divide in half.

Degree- is a unit of angular measurement.

Divider- is a device used to transfer measurements or to scribe arcs on hard

Surfaces.

Hexagon- is a polygon with six sides.

Octagon- is a polygon with eight sides.

Pentagon- is a polygon with five sides.

Radius- is the length of a straight line connecting the center of a circle with

a point on the circumference of a circle.

Vertex- is a point in the intersection of two or more sides.

Inscribe- means a polygon is drawn inside a circle.

Circumscribe- means a polygon is drawn outside the circle.

Tetrahedron- is a solid with four triangles.

Hexahedron- is a cube.

Octahedron- is a solid with eight triangles.

Dodecahedron- is a solid with twelve pentagons.

Icosahedron- is a solid with twenty triangles.

Prism- has two bases which are parallel equal polygon.

Pyramid- has a polygon for a base and triangular lateral faces intersecting

at a common point called vertex.

Cylinder- is generated by a straight line called the generatrix, moving in

contact with a curve line and always remaining parallel.

Cone – is generated by a straight line moving in contact with a curved line in

passing through a fix point.

Sphere- is generated by a circle revolving about one of each diameter.

1




Learning Outcome 1: Bisect lines, Arcs, Circles and Angles

Assessment Criteria

1. Drawing tools and instruments in bisecting lines, angles and arcs are

identified.

2. Appropriate steps and procedures are demonstrated in bisecting lines,

arcs, circle and angle.

3. Geometric figures are accurately constructed.

4. Proper handling of drafting tools and equipment is observed.

5. All drafting tools, equipment and materials are well taken care of.

6. Safety work habits are manifested.

References:


Company: 1949.


editon: 1960



1977

2

LEARNING EXPERIENCES/ ACTIVITIES

Learning Outcome # 1: Bisect lines, arcs, circles, and angles.



on bisecting lines, arcs,

circles, and angles.

2. Answer self check no. 1.1

3. Check your answers using the

answer key.

4. Read operation sheet no. 1.1

about the procedure in

bisecting lines, arcs, circles,

and angles.

5. Perform task on self check no.

1.2.

6. Review the steps in operation

sheet no. 1.1 if some steps

were not properly

demonstrated.

Try to answer self-check no. 2.1.

Try to perform the said

Activity.

Consult your teacher on the

items which are difficult to

perform.

3


LO1 : Bisect lines, arcs, circles and angles

Geometric Construction

Constructing Geometric Forms with drawing instruments is always

observed in Technical Drawing. They are in the form of lines, angles, ellipses,

quadrilaterals, solids, circle and polygons.

Classifications of Drawing Tools

Scrubing

Care and Maintenance of Drawing Tools

Do not use compass or divider as pick.

Never use the edge of straight ledge in cutting with knife or cutter.

Use clean dump cloth in cleaning the T – Square & Triangle.

Never use the triangular scale in drawing lines.

Always use a sharp pencil.

Triangular Scale

Triangles

T-square

Divider

Compass

Circular Templates

emplates

Divider

Compass

Foot Rule

Triangles

T-square

Foot Rule

Measuring Straight Edge Inscribing Dividing

4

Proper Handling of Drafting Tools & Equipment

Use T-Square in drawing horizontal lines.

Use triangles in drawing vertical & inclined lines.

Hold the compass by the handle while making circular features.

Hold the pencil 60º angle while drawing.

Safety Reminders to Remember while Drawing

Be sure to keep your hands and instruments clean.

Never sharpen pencil over your board while working.

Avoid eating sticky and wet food while drawing.

Always listen to the instruction of the teacher on how a drawing

will be done.

Concentrate. A person who concentrates well in his work will be

able to do work accurately, neatly and will be able to finish at the

given time frame.

5

Operation Sheet No. 1.1

LO1 : Bisect Lines, Arcs, Circles and Angles

Steps in Bisecting Lines

1. Given Line AB

2. Strike arcs greater than the radius with points A and B as centers.

3. Through the intersections of the arcs at 1 and 2, draw a light vertical line.

This line will divide the given line AB at point O. Line AO equals line OB.

A B

A B

A B O

1

2

6

Steps in Bisecting Arc

A B

B A

1.Given an Arc AB connect the extremities of the arc with a straight line.

Use the same procedure as in bisecting a line.

7

Steps in Bisecting Angle

.

A B

O

2. Strike arcs passing through the given arc. Connect the two intersections with a

line to reveal your bisected arc. Arc AO equals arc OB.

B A

C

8

1.Given an angle ABC, With B as center, strike an arc in any convenient

radius passing through the given angle and name the intersections

1 and 2

2. Now strike another arc using the intersections 1 and 2 as your centers.

3. Connect vertex of angle (B) to intersecting arcs (O) for angle’s

bisector. Angle ABO equals angle OBC.

B A

C

1

2

B A

C

1

2

B A

C

1

2

O

9

Steps in Bisecting Circle

1.Given a circle strike an arc from the circumference greater than the

radius.

10

2. Repeat Step 2 at the opposite through approximation. Your arc this time

intersects the existing arcs.

3. Now connect the two intersecting arcs with each other with a line

tocomplete your bisected circle.

11

SELF – CHECK 1.1

LO1. Bisect Lines, Arc, Circle and Angle

.

I. DIRECTION: Read each sentence carefully. Choose the letter that

corresponds to your answer. Write the letter of the

correct answer on the space provided.

-------------1. A tool used for drawing circular features.

a. compass b. Triangle c. T-Square d. Protractor

-------------2. Which of the following is the primary use of the T-square?

a. Drawing vertical lines

b. Diagonal lines

c. Drawing horizontal lines

d. Scribing circular features

-------------3. This tool is used to measure out distances.

a. Triangular scale b. Protractor c. Compass d. Divider

-------------4 Dividing lines requires the use of____________________.

a. Circular template b. Protractor c. Divider d. French

curve

--------------5. The following are ways in handling drafting tools and

equipment properly EXCEPT:

a. Hold the pencil 60º angle while drawing.

b. Use T-square line drawing horizontal lines.

c. Always use a sharp pencil.

d. Use the triangles in drawing vertical & inclined lines.

12

II Enumeration:

Give 5 safety reminders to remember while drawing.

1.

2

3

4.

5.

13

SELF – CHECK # 1.2

LO1. Bisect lines, arc, circle and angle

Procedure:

1. Prepare drawing instruments.

2. Perform bisecting line, arcs, circles and angle on the following

given figures.

Bisect lines

14

Bisect arcs.

Bisect an angle.

Bisect a circle.

15




Learning Outcome 2: Draw regular polygons Assessment Criteria:

1. Regular polygons are correctly identified.

2. Appropriate steps and procedures are demonstrated in drawing

regular polygons.

3. Tools and instrument in drawing regular polygons are identified.

4. Regular polygons are drawn according to standard specifications.



References:


Company: 1949.





1977

16


Learning Outcome # 2: Draw Regular Polygon


1. Read information sheet no. 2.

about the kinds of polygon.

2. Perform operation sheet no.

2.1

3. If the 80% level of accuracy

was not achieved, go over

again with the activity.

4. Proceed to operation sheet no.

2.1.

5. If there are items not perfectly

done in the job sheet, repeat

the activity.

Try to perform the said activity

with 80% level of accuracy.

Try to perform the job sheet for

self checking.

17


LO2. Draw regular polygons

Polygons

A polygon is a plane figure bounded by straight lines.

Regular Polygons

If a polygon has equal angles & equal sides, it can be inscribed in or

circumscribed around a circle

Inscribe Circumscribe

Common Regular Polygon

Triangle square pentagon hexagon octagon

18

OPERATION SHEET # 2.1

LO2. draw regular polygon

Procedures:

1. Draw a 4 cm. horizontal line (fig. 1)

2. Extend the line with its same length. (fig. 2)

FIGURE 2

FIGURE 1

19

3. Draw a semi circle, using the center of the combined line

which endpoints will be its diameter (fig. 3).

FIGURE 4

FIGURE 3 4. Now, divide the semi-circle into 6 equal parts as if you were

slicing a pizza. The 6 parts are the hexagon’s number of equal

sides. (Fig. 4).

20

5. Bisect the third line from your extended line (See fig. 5)

FIGURE 6

FIGURE 5

6. Now bisect your given line (See fig. 6).

21

FIGURE 8

8. Draw a circle. The intersection from fig. 7 will be the center of your circle and one of the endpoints of your given line will serve as your radius (Fig. 8).

FIGURE 7

7. Connect the two bisectors of your line to locate the center of your circumscribed hexagon ( Fig. 7).

22

10. Connect intersections of the lines that were extended to other

intersection of your extended lines (fig. 10).

Note:

Teacher may use other methods.

FIGURE 10

FIGURE 9

9. Extend your divided line to the circumference of your circle.

23

SELF – CHECK NO. 2.1

LO2. draw regular polygon Direction: Referring to your operation sheet #2.1, draw a Circumscribed pentagon. Given: 4 cm line

24




Learning Outcome 3: Draw regular solids

Assessment Criteria:

1. Regular solids are correctly identified.

2. Tools and instruments in drawing regular solids are identified.

3. Regular solids are drawn according to exact shape.



Resources:


Company: 1949.





1977

25


Learning Outcome # 3: Draw regular solids



about the kinds of solid.

2. Perform self check no. 3.1.

3. If the activity was not properly

accomplished, practice again to

achieve accuracy.

4. Answer self check no. 3.2

Try to perform the said activity for

self checking.

26


LO3. Draw regular solids Drawing Regular Solids

Solids - are figures bounded by plane surfaces. The five regular solids

Tetrahedron, Hexahedron, Octahedron, Dodecahedron, Icosahedron

(4 triangles) (cube) (8 triangles) (12 pentagons) (20 triangles)

Prism- has two bases which are parallel equal polygon and three or more

lateral faces which are parallelogram.

Right Right Oblique square rectangular rectangular

Pyramid- has a polygon for a base and triangular lateral faces intersecting

at a common point called vertex.

Right Right Square Oblique Triangular pentagonal

27

Cylinder- is generated by a straight line called the generatrix, moving in contact with a curve line and always remaining parallel.

Right Oblique Circular Circular

Cone – is generated by a straight line moving in contact with a curve line in

passing through a fix point.

Right circular Oblique circle Oblique circle (frustum) (truncated) Sphere- is generated by a circle revolving about one of each diameter.

28

SELF CHECK # 3.1

LO3. Draw regular solids

Procedure:

1. Draw regular solids and label them properly. ( Dimension is optional )

29

SELF CHECK # 3.2

LO3. Draw regular solids

Direction: Write the correct answer on the space provided before each

number.

___________________________1. It is a solid with eight triangles.

___________________________2. It is a regular solid with four triangles.

___________________________3. It is a cube solid.

___________________________4. A regular solid with twenty triangles.

___________________________5. A solid composed of twelve pentagon.

30



Scoring Rubrics


Accuracy

50

45

40

Speed

10

6

8

Neatness

25

20

15

Lettering/Labeling

15

12

10

8

Total





Speed




Neatness

25 pts. - has no error

20 pts - has two to three erasures

15 pts - has four or more erasures

31

Lettering/Labeling

15 pts. - All pieces of information are completely indicated and 12

legibly printed.

pts. - All pieces of information are legibly printed but some are

missing.

10 pts. - All pieces of information are legibly printed but some are

missing and misspelled.

8 pts. - Pieces of information are not legibly printed and words are

misspelled.

2

ANSWER KEY 1.1

Test I.

1. a

2. c

3. b

4. c

5. a

Test II. Enumeration.

1. Be sure to keep your hands and instruments clean.

2. Never sharpen pencil over your board while working.

3. Avoid eating and touching sticky and wet thing while drawing.

4. Always listen to the instruction of the teacher on how a drawing

will be done?

5. Concentrate. A person who concentrates well in his work will be

able to do work accurately, neatly and will be able to finish at the

given time frame.

3

ANSWER KEY 1.2

( Teacher’s check)

Self-Check 1.2

4

ANSWER KEY 2.1

( Teacher’s check)

Self-Check 2.1

5

ANSWER KEY 3.1

a. Octahedron

b. Tetrahedron

c. Hexahedron

d. Icosahedron

e. Dodecahedron

Unit of Competency: Construct Orthographic Projection

Module No.: 3 Module Title: Constructing Orthographic

Projection



HIGH SCHOOLS

ACKNOWLEDGMENT


First Published JUNE 2008

This draft was prepared at the Competency-Based Learning Materials Development Workshop conducted at the Marikina Hotel, Marikina City on February 18-22, 2008 and Development Academy of

the Philippines (DAP) on May 5-10, 2008.

This learning instrument was developed by the following personnel:


Mario S. Gregorio, Ed.D. Tagum National Trade School Tagum City, Davao del Norte, Region XI


Bauan, Batangas

Ariel F. Maglalang Assemblywoman Felicita G. Bernardino

Memorial Trade School, Lias, Marilao, Bulacan, Region III Juanito Bugaoisan



Mabalacat, Pampanga

Facilitator: Aida T. Galura

Angeles City National Trade School Sunset Valley, Angeles City

Encoders:






Technology Teachers: Mario S. Gregorio Ed. D.

Tagum National Trade School Tagum City, Davao del Norte, Region 11

Condrado C. Casulla Pangasinan School of Arts and Trades

Lingayen, Pangasinan, Region 01 Nelson M. Arisga

Malvar National High School Malvar, Batangas, Region 4A

Alexander M. Latoga Manuel S. Enverga Memorial College of Arts and Trades

Mauban, Quezon, Region 4A Mirasol F. Dasig

San Pedro Relocation Center National High School San Pedro, Laguna

Region 4A Contextual Writer:

Marvin R. Viernes Muntinlupa Business High School

Muntinlupa City, NCR

Encoder:




Quezon City

Facilitator:

Orlando E. Manuel PhD Principal

Cabarroguis National School of Arts and Trades Cabarroguis, Quirino Region 02

This work was produced with funding provided by the

Department of Education. REFERENCES AND FURTHER READING


Company: 1949.


editon: 1960




How to Use this Module ……………………………………………….. I Introduction ……………………………………………….. ii Technical Terms …………………………………………………………. iii Learning Outcome 1 –Construct Orthographic Views ………………….. 1



Operation Sheet 1.1 …………………………………………… 14

Self – Check 1.1 …………………………………………………….. 28

Self - Check 1.2 …………………………………………… Self -Check 1.3 ……………………………………………………… Self -Check 1.4 …………………………………………………..

29 30

31

Operation Sheet 1.2 ………………………………………….. 34

Self – Check 1.5 …………………………………………………….. 38

Self – Check 1.6 …………………………………………………….. 39

Self – Check 1.7 …………………………………………………….. 40

Learning Outcome 2 – Apply General Specific Dimensions ……… 41

Learning Experiences/Activities ………………………………….. 42


Self Check 2.1 ………………………………………………………… 45

Self Check 2.2 ………………………………………………………… 47

Assessment Resources ………………………………………………….. 49

Answer Key ………………………………………………….. 51-57










assessment is given to check if you are already competent with the specified

learning outcome/s and ready for the next task.


Program/ Course : TECHNICAL DRAWING I

Unit of Competency : CONSTRUCT ORTHOGRAPHIC PROJECTIONS

Module Title : Constructing Orthographic Projections

INTRODUCTION Orthographic Projection is the graphical representation of the different

views of an object to show the necessary information. Through this module,

a student can construct two forms of orthographic projection such as

orthographic views and pictorial views. Orthographic views represent front

view, top view, right side view, bottom view, rear view and left side view while

pictorial view represents a complete shape of an object.

Also, through this module, a student can apply general and specific

dimension: the height, width, and depth of an object.



LO1 Construct Orthographic Views

LO2 Apply general and specific dimensions

TECHNICAL TERMS

Orthographic - is a method of representing three dimensions.

Projection- is an object on a plane having only length and breadth.

Right Angle – is an angle with a measure of 90 degrees.

Dimension – is a radial or linear length (width, height, depth) labeled on a

technical drawing.

Measurement – is the process or result of measuring anything.

Metric system of measurement – is an international system of

measurement

English system of measurement- is an American standard system

of measurement

Metric – pertains to the metric system of measurement.

Dimensioning – is an act of measuring a drawing.

5




LO1.Construct orthographic views


1. Principles of orthographic projection are clearly explained and

discussed.

2. Projection of principal views is clearly demonstrated.

3. Principal views are accurately constructed based on a given pictorial.

4. Supplying missing lines is accurately solved and illustrated.

5. Proper manipulation of drafting tools and equipment is performed.

6. Safety work habits are highly practiced.

References:


Company: 1949.


edition: 1960


Norman Stirling. Introduction to Technical Drawing; Delmar Publishin

5


Learning Outcome # 1: Construct Orthographic Drawing


1. After reading the information

sheet no. 1 and 2, you are

required to answer the self

check 1.1.

2. Given the operation sheet no.

1.1, read and perform the

procedure in constructing

orthographic views on self

checks 1.2, 1.3, 1.4.

3. Proceed to operation sheet no.

1.2, read and analyze the

operating steps in

constructing pictorial view.

4. Perform the task on self

checks no. 1.2, 1.3, 1.4.

Ask your teacher for further

clarification on items not clear

to you.

When you are through with the

activity, review/ check your

work.

5

MEDIUM

MEDIUM


LO1. Construct orthographic drawing

Orthographic projection is a method of representing the exact shape

of the object by dropping two or more perpendicular to a plane generally at

right angle.

As basic requirement in performing drawing activities, the students

must have the basic knowledge on alphabet of lines.

The following are the basic alphabet of lines that are used in

orthographic drawing.

1. Visible lines – Used to show visible edges or contours of an object

(NOTE: Visible lines are sometimes called object lines.)

2. Hidden lines – Represented by a series of medium weight dashes used

to show the hidden or invisible edges of an object.

5

THIN

THIN

3. Center lines – Used to show the centers of holes of circular object

or shape.

4. Section lines – Used to show a surface that has been cut in a section

view. The surface indicated with section line is presumed to be solid

portion.

5. Extension lines – Indicates the limit of a dimension line.

MEDIUM

5

6.Dimension lines – Used to show the size (dimensions) of an object; spans

from one extension line to the next, has arrowhead at both ends, and is

broken in the middle fro the measurement number (dimension).

7.Leader lines – Used to direct descriptive major information, notes, or

special dimensions to features on the drawing and done mechanically.

8.Cutting-plane lines – Used to show where a section has been taken;

arrows on the end show the direction in which the section was taken.

9.Break lines – Used to show that part of the object has been removed or

broken away

a. Short break lines are for freehand, jagged lines and applicable

for small objects only.

THIN

THICK

Both are

cutting plane lines

LEADER LINE

THIN

MEDIUM

5

b. Long break lines are solid with a Z symbol inserted in several

places and done mechanically and applicable for big objects

only.

10.Reference line – an irregular fine curve line with an arrowhead at one

end used for indicating the measurement and name of a part.

Two Methods of Shape Representation

A. Orthographic Views

B. Pictorial Views (Refer to Operation Sheet #1.2)

Orthographic view-is a representation of two or more separate views. This

can be represented into six principal views and regular views

1. The Three Regular Views

Orthographic views can be represented by two or more separate views,

however, it is advisable to illustrate three views to show clear and detail

presentation of at least three principal views of the object. The following are:

1. Top View

2. Front View

3. Side View

THIN

MEDIUM

5

Fig. 1. Three Regular Views

2. The Six Principal Views (see Fig. 2)

1. Top View. It is drawn above the front.

2. Front View. It is drawn vertically aligned and below

the top view

3. Right Side View. This located at the right side and aligned

with the front view.

4. Left Side View. The opposite of the right side view. It is located

at the left side and aligned with the front view.

5. Rear View. The opposite view of the front view. It is located

aligned after either at the right side view or left

side view.

6. Bottom View. The opposite view of the top view. This must be

drawn vertically aligned and below the front view.

TOP VIEW

FRONT VIEW

SIDE VIEW

5

FRONT VIEW REAR VIEW

REAR VIEW

RIGHT SIDE VIEW

LEFT SIDE VIEW

BOTTOM VIEW

Fig. 2 shows the six principal views. Further, it shows the proper location of the top view, front view, right side view, left side view, rear view, and bottom view

TOP VIEW

Plan View or Top View This can be little more difficult to visualize because you have to imagine

yourself moving over the top of the object and looking vertically downward. The left-

hand and right-hand illustration on the next page show how the plan is placed

above the front. Again, sketch the light vertical construction lines to locate the plan

in its proper position. Draw these upward from each corner of the front view and

line-in the plan of the right.

5

Front View Concentrate on the front view. If you look at it correctly the effect will

be seen below at the left, while the below right illustration shows what you

will actually see. Notice that in the left-hand drawing, you can only see the

dark-inked front “face” of the object. Notice also that you cannot see any of

the other sides of the object. This is because all those sides are “going away”

from you in your line of sight and are simply not visible from your view

point. They are still there, of course, but are hidden behind the outer edges

of the first face.

FRONT VIEW

TOP VIEW

5

FRONT VIEW RIGHT- SIDE VIEW

The right-side view drawn at the right of the front view

CORRECT VIEWING OF THE FRONT FACE

THE FRONT VIEW AS SEEN

FRONT VIEW

Right-Side View Right-side view should be drawn at the right side of front view. Imagine

moving around the object to look directly at its right side. How you see it is

shown below-left and what you see is shown below-right. Again the faces you

actually see are heavily outlined.

5

Pictorial View is a representation of a complete shape of the object.

Pictorial View of a Step Block

CORRECT VIEWING OF THE RIGHT-SIDE FACE

RIGHT- SIDE VIEW AS SEEN

5

Identifying the vertical and horizontal view

The Space Dimension

This refers to the three dimension standards of the pictorial view such

as: height, width, and depth.

Height is the distance elevation from top to bottom.

Width is the distance from left side to the right side.

Depth is the distance from front to rear.

WIDTH DEPTH

HEIGHT

Fig. 3 shows the illustration of pictorial view

5

The ten principles to be considered in constructing orthographic

drawing/projection are:

1. Top view is directly above the front view.

2. Side views are horizontally aligned with the front view and rear

view.

3. The width of the top view is equal to the width of the side view.

4. When a line or edge is viewed perpendicularly to a plane or

surface, projection will appear as a point.

5. A line or edge parallel to a plane of projection will also appear as a

line or edge in its exact shape or true length.

6. A line or edge inclined to the plane of projection will appear shorter

or foreshortened.

7. A surface perpendicular to the plane will appear as a line or edge

equal in length to the nearest edge of the surface which in this

case is either its length or its width depending on its position.

8. A surface parallel to the plane of projection will be shown in its

exact or true shape and size.

9. A surface inclined to the plane of projection will also appear as a

surface but smaller in size and shape.

10. No line or edge of the object can be projected longer than its true

length.

5


LO1. Construct orthographic views

Condition or Situation for the Operation:

Given pictorial view with corresponding dimensions and draw the

three regular views.

Equipment, Tools and Materials:

T-Square, triangle (30 x 60, 45 x 45), French curve compass, elliptical

template, drafting knife, butt paper and eraser

Procedure: (See follow-up illustration on the next page)

To draw orthographic views of the given pictorial view, first determine

the number of views needed, then decide which surface will become the front

view. Establish the space needed between views for dimensioning and

calculate the center of the drawing, then proceed to the following steps.

PICTORIAL DRAWING

5

STEP 1. Draw the vertical and horizontal axis.

5

STEP 2. Divide the axis by indicating marking lines

according to the given dimensions of the width of

the top view, height of the front view and space

between top view and front view.

Length

FRONT VIEW

Space between top view and front view

5

STEP 3. Construct the enclosing box of the top view and front view by

projecting the marking lines horizontally and vertically.


FRONT VIEW

5

STEP 4. Construct diagonal line at 45 degrees angle using

45 deg. X 45 deg. Triangle from the upper right

corner of the enclosing box of the front view.

Length

FRONT VIEW

450


5

STEP 5. Project down the two intersecting points to get the

width of the right side view and to form its

enclosing box.

Length

FRONT VIEW

450

INTERSECTING POINT

5

STEP 6. Divide proportioning distance of top view and

front view by indicating marking lines.

Length

FRONT VIEW

450

INTERSECTING POINT

5

STEP 7. Draw the details of top view front view and side

view by projecting the marking lines horizontally

and vertically.

FRONT VIEW

450

INTERSECTING POINT

5

STEP 8. Darken the final edges of the top view, front view

and right side view

FRONT VIEW

450

INTERSECTING POINT

5

FRONT VIEW

450

INTERSECTING POINT

STEP 9. Divide the provided space for dimensioning by

indicating marking lines.

5

FRONT VIEW

450

INTERSECTING POINT

STEP 10. Sketch light lines for dimension lines and

extension lines by projecting the marking lines

horizontally and vertically.

5

STEP 11. Draw final dimension lines and extension lines.

.

.

FRONT VIEW

450

INTERSECTING POINT

40

5

STEP 12. Indicate the measurements.

.

.

FRONT VIEW

450

INTERSECTING POINT

10 10

40

30

10

12

40

16

5

Evaluation:

Teacher evaluates using the following criteria:

1. All operating steps in the construction of the given problem are

correctly followed.

2. The object is accurately drawn according to the given measurements.

3. All drawing instruments used in the drawing are properly

manipulated according to the standards.

4. The drawing is neatly done.

STEP 13. Label the top, front and right side views.

Finally, erase the construction lines.

.

.

FRONT VIEW

10 10

40

30

10

12

40

16

TOP VIEW

RIGHT SIDE VIEW

5

SELF CHECK # 1.1

Direction: On the blank provided before each item, write the words that

make the sentence complete and correct.

_________1. Dimension line must be terminated by an _____________.

_________ 2.The length of arrowhead must be _________________.

_________3. It is a thin and dark solid line that extends from a point on

the drawing to which the dimension refers.

_________4. It is a gap, and a distance of the extension line to the object.

_________5.It is the exact width of the arrowhead.

_________6. The distance from front to rear.

_________ 7. It is the opposite view of the top view.

_________ 8. The first step in constructing orthographic drawing.

_________ 9. It is the opposite view of the front view.

________ 10. It is the distance between object outline and dimension line.

5

SELF CHECK # 1.2

Direction: Given the pictorial view, construct the three orthographic views.

PICTORIAL VIEW

5

SELF CHECK # 1.3

NOTE: ALL DIMENSIONS ARE IN CENTIMETERS

50

13

50

13

50

50

3838

50

13

20

50

40

25

60

50

25

15

15

20

DIRECTION: Given pictorial drawing, solve the three

Regular views

5

SELF CHECK # 1.4

DIRECTION: Given pictorial drawing, solve the three Regular views

NOTE: ALL DIMENSIONS ARE IN CENTIMETERS

50

13

50

13

50

50

3838

50

13

20

50

40

25

60

50

25

15

15

20

45

5

Other suggested Activities:

Direction: Supply the missing visible and hidden lines in the Orthographic

views below.

A B

5

Direction: Supply the missing visible and hidden lines in the pictorial

drawings below.

5


LO1. Construct orthographic drawing

Condition or Situation for the Operation:

Given the three orthographic views with corresponding dimensions,

draw the orthographic drawing (pictorial view).

Pictorial View – a drawing that represents the complete shape of an object.

Below demonstrates how pictorial drawing is constructed.

16

34

18 24

10

10

24

26

10

TOP VIEW

FRONT VIEW RIGHT SIDE VIEW

5

Equipment, Tools and Materials:

T-Square, triangle (30 x 60, 45 x 45), French curve compass, elliptical

template, drafting knife, butt paper, and eraser.

Procedure: (See follow-up illustration on the next page)

Precaution:

Observe and practice the proper uses and care of the drawing

instruments.

Evaluation:

Teacher evaluates using the following criteria:

1. All operating steps in the construction of the given problem are

correctly followed.

2. The object is accurately drawn according to the given measurements.

3. All drawing instruments used in the drawing are properly

manipulated according to the standards.

4. The drawing is neatly done.

STEP 1. Draw the axis (Use 30 x 60 triangle for inclined axis).

5

STEP 2. Lay out the proportion of an object in the enclosing box for the whole object or principal portion of it.

STEP 3. Project measurements.

STEP 4.

Divide one axis

STEP 4. Sketch the enclosing box.

5

STEP 5. Divide one axis for proportioning

distance and sketch the most

dominant detail of the object.

STEP 6. Complete the construction details.

STEP 7. Darken the final edges and erase the construction lines.

5

SELF CHECK # 1.5

Direction: Given the three orthographic views, construct a pictorial view.

TOP VIEW

50 30

15

FRONT VIEW SIDE VIEW

35

5

5

SELF CHECK # 1.6

DIRECTION: Given the three orthographic views, draw the Pictorial view.

TOP VIEW . 27 60 10 FRONT VIEW R. SIDE VIEW

10

12

20

1

0

50

5

SELF CHECK # 1.7

DIRECTION: Given the orthographic views, draw the pictorial. TOP VIEW 5 10 10


27

10

12

40

10

1

0

5

45

20

42




LO2. Supply general and specific dimensions


1. Measurements are correctly converted from English to Metric.

2. Dimensioning is manually/CAI- supplied on orthographic and

isometric drawing in accordance with standard specifications.

3. All dimensions using notation on special features of object are

supplied accordingly.

References:


Company: 1949.


editon: 1960



1977

43


Learning Outcome # 2: Supply General and Specific Dimension


2. Read the information sheet no.

2 on conversion of

measurement.

3. Answer the self check no. 2.1.

Compare your answer to the

answer key.

4. Go back and review the

information if some items are

not correctly answered.

Try to answer the self check no.

3.2 the best you can.

44


LO2. Supply general and specific dimension

Dimensioning

Dimensions are given in the form of linear distances, angles or notes

irrespective of the dimensioning units being used.

The following are the essential elements to be considered in

dimensioning technique:

1. character of lines

2. spacing of the dimensions

3. the arrow heads

4. the use of extension lines.

The arrow heads indicate the direction and extent of a dimension. It

should be uniformed in size as 3mm. length width.

Spacing of the dimension lines

The dimension nearest to the object being outlined should be spaced

at least 10 mm. away. All other dimension lines should be at least 6 mm.

apart. However, if more space is available, the spacing of dimensions line

should be uniformed throughout the drawing.

Extension line

A thin and dark solid line that extends from a point on the drawing to

which a dimension refers. The dimension line meets the extension lines at

right except in special cases. A gap distance of at least 2 mm. from the object

outline should extend about 3 mm. (1/8) beyond the outermost arrowhead.

45

System of Measurements

There are two systems of measurement applied in drawing such as English and metric.

1. English System

As used in drawing, specifically refers to inches and feet unit of measurement

2. Metric System

It is an International System (IS) of measurement as applied in drawing. This is based upon the meter or millimeter as a linear unit of measurement

Metric Equivalent (Commonly used in drawing) 1 inch = 2.54 centimeters = 254 millimeters 1 foot = 30.5 centimeters = 305 millimeters 1 foot = .305 meter

How to Convert English System to Metric System? Example 1: To convert 18 inches to centimeters 18 in X 30.5 cm

12 in

= 18 X 30.5 cm

12

= 18 X 2.54 cm

= 45.7 cm

Example 2: To convert 84 centimeters to inches

84 cm X 12 in 30.5 cm = 84 X 12 in 30.5 = 31.6 inches

46

SELF CHECK # 2.1

LO2. Supply general and specific dimension Direction: A. Fill in the blanks.

_____________________1. A form of linear distances, angles, or notes

irrespective of the dimensioning units being used.

_____________________2. It is the length of the arrowheads.

_____________________3. It is a thin and solid line that extend from a point

on the drawing to which the dimension refers.

_____________________4. It is a gap distance between extension line and

object line.

_____________________5. It is the exact width of the arrowhead.

B. Enumeration

1. Identify the two systems of measurement.

a.

b.

2. Recognize the essential elements to be considered in dimensioning.

a.

b.

c.

d.

C. Problem Solving

1. Convert 32 inches to centimeter.

2. Convert 6 inches to centimeter.

47

D. Direction: Given the three orthographic views, supply the missing general Dimensions of the top view, front view, and side view.

TOP VIEW


?

50

40 ?

60

? 15 15

20

20

48

SELF CHECK # 2.2 Direction:

I. On the blank provided before each item, write the word or group of words

that will make the sentence complete and correct.

_________1. Dimension line must be terminated by a _____________.

_________ 2.The length of arrowhead must be _________________.

_________3. It is a thin and dark solid line that extends from a point on

the drawing to which the dimension refers.

_________4. It is a gap and a distance of the extension line to the object.

_________5.It is the exact width of the arrowhead.

_________6. The distance from front to rear

_________ 7. It is the opposite view of the top view

_________ 8. The first step in constructing orthographic drawing

_________ 9. It is the opposite view of the front view

________ 10. It is the distance between object outline and dimension line

II. Enumeration:

1. Give the two systems of measurements

a.

b.

2. Identify the essential elements to be considered in dimensioning

a.

b.

c.

d.

49

3 Enumerate the six principal views according to their standard

placement.

a.

b.

c.

d

e

f.

4. Identify the two methods of shape representation.

a.

b.

5. Identify the three-space dimensions.

a.

b

c

III Essay type

1. Discuss briefly the following;

a. Pictorial View

b. Orthographic Projection

c. Dimensioning Technique

IV. Illustrate the steps in constructing orthographic drawing based on the

given pictorial view.

50



Scoring Rubrics


Accuracy

50

45

40

Speed

10

6

8

Neatness

25

20

15

Lettering/Labeling

15

12

10

8

Total





Speed




Neatness

25 pts. - No errors made on the output.

20 pts - Two to three erasures made on the output.

15 pts - Four or more erasures made on the output.

51

Lettering/Labeling

15 pts. - All information must be completely indicated and legibly

printed.

10 pts. - Pieces of information are legibly printed but some are

missing.

52

ANSWER KEY # 1.1

I. 1. arrow heads 2. 3mm 3. extension line 4. 2mm 5. 2mm 6. depth 7. bottom view

8. draw axis 9. rear view 10. 10 mm

53

ANSWER KEY 1.2

TOP VIEW

30

.


10

2

0

25

10

15

30

10 20

10

40

10 20

54

ANSWER KEY 1.3

PICTORIAL VIEW

55

ANSWER KEY 1.4

(Teacher’s Check)

Self-check 1.4

56

ANSWER KEY 1.5

(Teacher’s Check)

Self-check 1.5

57

ANSWER KEY 2.1

A. 1. Dimension 2. 3mm 3. Extension line 4. 2mm 5. 2mm

B.

1. a. English system b. Metric system

2. a. Character of lines b. Arrow heads

c. Extension line d. Distance/ Spacing of dimensions C.

1. 81.33 cm 2. 15 cm

D. (Teacher’s check)

58

ANSWER KEY # 2.2

I.

1. arrow heads 2. 3mm 3. extension line 4. 2mm 5. 2mm 6. depth 7. bottom view 8. draw axis 9. rear view 10. 10 mm

II. 1. a. English System b. Metric System 2. a. Character lines b. dimension line c. extension line d. spacing of the dimension line 3. a. top view b. front view c. right side view d. left side view e. rear view f. bottom view 4. a. orthographic view b. pictorial view 5. a. height b. width c. depth

Unit of Competency: Constructing Pictorial Drawing

Module No.: 4 Module Title: Constructing Pictorial Drawing



HIGH SCHOOLS

ACKNOWLEDGMENT


First Published JUNE 2008 This draft was prepared during the Competency-Based Learning

Materials Development Workshop conducted at the Marikina Hotel, Marikina City on February 18-22, 2008 and Development Academy of

the Philippines (DAP) on May 5-10, 2008. This learning instrument was developed by the following

personnel:

Technology Teachers: Mario S. Gregorio, Ed.D.

Tagum National Trade School Tagum City, Davao del Norte, Region XI


Bauan, Batangas

Ariel F. Maglalang Assemblywoman Felicita G. Bernardino Memorial Trade School, Lias, Marilao, Bulacan, Region III

Juanito Bugaoisan



Mabalacat, Pampanga Facilitator:

Aida T. Galura Angeles City National Trade School

Sunset Valley, Angeles City

Encoders:

Mel Contapay Office of Legal Affairs Department of Education

Meralco Ave., Pasig City Maria Riza Zamora

DepED Budget Division Meralco Ave., Pasig City


Curriculum and Competency-Based Learning Materials was done in

Marikina Hotel, Marikina City on April 13-18, 2009 through the concerted effort of the following writers:


Mario S. Gregorio Ed. D. Tagum National Trade School Tagum City, Davao del Norte, Region 11

Condrado C. Casulla


Nelson M. Arisga Malvar National High School Malvar, Batangas, Region 4A

Alexander M. Latoga




Contextual Writer: Marvin R. Viernes

Muntinlupa Business High School Muntinlupa City, NCR

Encoder:

Lawrence D. Cruz DepEd EID-TS DepEd Complex Meralco Ave.

Quezon City Jeffree O. Ponce

DepEd EID-TS DepEd Complex Meralco Ave.

Quezon City Facilitator:

Orlando E. Manuel PhD

Principal Cabarroguis National School of Arts and Trades Cabarroguis, Quirino

Region 02




Company: 1949.


editon: 1960




How to Use this Module ……………………………………………….. I Introduction ……………………………………………….. ii Technical Terms …………………………………………………………. iii Learning Outcome 1 Construct Isometric Drawing …………………… 1


Information Sheet no. 1.1 ……………………………………… 3

Operation Sheet no. 1.1 ………………………………………… 4

Operation Sheet no. 1.2 ………………………………………… 7

Self check no. 1.1 ……………………………………………….. 10

Self check no. 1.2 ……………………………………………….. 11

Learning Outcome 2 – Construct Oblique Drawings ……….. …………. 12


Operation Sheet 2.1 ……………………………………………… 15

Self check no. 2.1 ……………………………………………….. 19

Learning Outcome 3 – Construct Perspective Drawings ……………… 20

Learning Experiences/Activities …………………………………….. 21


Operation Sheet 3.1 ……………………………………………… 24

Operation Sheet 3.2 ……………………………………………… 29

Operation Sheet 3.3 ……………………………………………… 32

Self check no. 3.1 ……………………………………………….. 34

Self check no. 3.2 ……………………………………………….. 35

Assessment Resources ………………………………………………….. 36-39

Program/ Course : TECHNICAL DRAWING 1

Unit of Competency : CONSTRUCT PICTORIAL DRAWING

Module Title : Constructing Pictorial Drawing

INTRODUCTION

Pictorial Drawing is used to communicate ideas which cannot be

described easily in words. It is used by engineers, architects and all types of

designers and drafters to illustrate the size and shape of an object.

This module is intended to show the student that pictorial drawing is

easier to understand and interpret because it shows height, weight, length in

one drawing than orthographic multi view drawing which shows only one

face of an object of each view.

The different types of pictorial drawing discussed here are isometric,

oblique, and perspective.



LO1 Construct isometric drawings.

LO2 Construct oblique drawings.

LO3 Construct perspective drawing.

TECHNICAL TERMS

Angles – refers to the space or opening between two straight lines that meet.

Oval – is elliptical shapes that resembles an egg.

Symmetrical – is a balanced arrangement between two sides.

Principles – are guiding rules to follow.

Parallel – is a perpendicular line equidistant from each other at all points.

Projection – is a line or object that shows a distance.

Circle – is a plane figure bounded by circumference which is equidistant

From a common point, the center.

Arc – is a portion or a segment of a circumference of the circle.

Picture Plane- is a location wherein the top view must be drawn.

Horizon Line- a line wherein the vanishing point must be located.

Ground Line- a line wherein the front view must be drawn.

Vanishing Point- a point wherein the vanishing line must be projected.

Vanishing lines- these lines are used to project the horizontal edges of the

object in order to make the object foreshortened. These

these lines are also called “receding lines”

Station Point- This is an imaginary point of the observer or viewer of an

object.

Bird’s Eye View- The object is viewed above the eye level of the observer.

Eye level- The object is viewed within the eye level of the observer.

Ant’s View- The object is viewed below the eye level of the observer.

1


Unit of Competency : CONSTRUCT PICTORIAL DRAWING


Learning Outcome 1. Construct isometric drawing

Assessment Criteria

1. The three divisions of axonometric are identified and discussed.

2. All principles of isometric drawing are properly discussed.

3. Procedure in constructing isometric drawing is followed according

to standard specifications.

4. Ellipse figure is accurately drawn in the form of isometric view.

References:


Company: 1949.


editon: 1960

German M. Manaois. Drafting 1 and 2; Phoenix Publishing:1983 Norman

Stirling. Introduction to Technical Drawing; Delmar Publishing: 1977

2


Learning Outcome # 1: Construct Isometric Drawing



about principles and

procedures of axonometric

drawing.

2. Perform operation sheet no.1.1

to test your understanding

about the principles and

procedures of axonometric

drawing.

3. If you were not able to get

some of the items, read again

the information sheet for

review.


1.2 about constructing ellipse

drawing.

5. If you were not able to get the

procedure, go over them until

you are able to master and

follow the said procedure.

o Try to perform the operation for

self checking.

o Try to perform the operation

sheet 1.2 to test your

understanding.

3


LO1. Construct isometric drawing

Axonometric Drawing is a pictorial drawing which shows the front

side and top faces of an object in one view. The receding lines in isometric

are always parallel.

Three Divisions of Axnometric Drawing:

o Isometric

o Dimetric

o Trimetric drawing

Principles of Isometric, Dimetric and Trimetric Drawing

o Isometric - All receding edges are 30º.

o Dimetric - One receding edge is 15º and the other one is 45º.

o Trimetric - All receding edges are 15º.

Ellipse is a closed curve in the form of a symmetrical oval.

Principles of Ellipse Drawing:

1. Isometric circles are drawn by drawing first the isometric

square which surrounds the given circle.

2. The four center ellipse procedure is sufficient for isometric

circle.

4



Procedure:

1. Draw the three isometric axes. Be sure that the angle of the cross axis is 30º from the lower edge of the paper .

2. Layout the principal measurements. Get the measurements from the Orthographic drawing.

30 0

30 0 30 degrees

5

3. Draw the box or crate lines.

4. Draw the details of the object.

30 0

6

5. Trace the visible edges with heavier lines.

6. If required, show hidden lines.

7. Label the isometric drawing.

7


LO1. Construct Isometric drawing

Procedure in Constructing Ellipse Drawing

Circle or Ellipse in Isometric Drawing.

Orthographic Circle Isometric of Circles

Steps in drawing Isometric Circles or Ellipses drawing using four-center

approximation methods:

1. Using 30o x 60o triangle and the T-square, draw the isometric

square box in the desired position. Follow the given radius or

diameter.

300 30

0

8

Horizontal Position Left Vertical Position Right Vertical Position

2. Draw 600 crate or construction lines from points B and D to

determine mid-points of each sides of the isometric square.

Horizontal Position Left Vertical Position Right Vertical Position B D D

B

B

D

9

B 1 1 1 2 D D 2 2 B D B

3. Set compass from points 1, & 2 to draw arcs. B 1 1 1 2 D D 2 B B 2 D

4. Set compass from points B and D to complete the isometric

circles or ellipse.

B

1 D 1 1 2 D 2 B B 2 D

5. Finalize the drawing.

10

SELF CHECK # 1.1


Direction: Given the three orthographic views, draw the isometric drawing.

RIGHT SIDE VIEW

TOP VIEW

40

12

16

10

30

40

10 10

FRONT VIEW

11

SELF CHECK # 1.2


Direction: Given the three orthographic views, draw the isometric drawing.

32.5

RIGHT SIDE VIEW

TOP VIEW

50

16

18

12

30

50

15

FRONT VIEW

20mm. dia.

12


Unit of Competency : CONSTRUCT OBLIQUE DRAWING


Learning Outcome 2. Construct oblique drawing

Assesment Criteria

1. Principle of oblique drawing is thoroughly discussed.

2 Two types of oblique drawing are correctly identified.

3. Steps in constructing oblique drawing are demonstrated according to

standard specifications.

4. Each type of oblique drawing is constructed.

References:


Company: 1949.


editon: 1960



1977

13


Learning Outcome # 2: Construct Oblique Drawing



about principles of oblique

drawing.


2.1 about the steps in

constructing oblique drawing.

3. If you did not get some of the

items, repeat the procedure,


for self checking.

14


LO2. Construct oblique drawing

Oblique Drawing is a pictorial drawing in which the front plane is

parallel to the plane of projection.

Two Types of Oblique Drawing:

1. Cavalier oblique-. This type of oblique drawing is drawn in its actual

measurement

2. Cabinet oblique-. This is a type of oblique drawing wherein the width

of objects is reduced by half of its size.

Principles of Oblique Drawing:

1. The longest measurement should be placed in front

2. Irregular shapes of the object should be placed in front to

minimize distortion

3. Arcs and circles in objects should be placed in front to minimize

distortion.

15

OPERATION SHEET 2.1

LO 2. Construct oblique drawing Procedure:

1. Draw the horizontal and vertical axes.

2. Determine the side or surface to be made parallel to the picture

plane.

16

3. Draw this surface in an orthographic form using the

horizontal and vertical axes as base lines. Get your

measurements from the given orthographic drawing.

4. Draw the cross-axis using 45o cross-axis for cavalier oblique and 30o cross- axis for cabinet oblique.

450

17

5. Draw the construction box.

6. Layout the measurements along the cross-axis. In a cavalier oblique, the

measurement is the actual size from the orthographic drawing. In a

cabinet oblique, the thickness is reduced in half.

450

18

6. Draw all visible edges.

19

SELF CHECK # 2.1

LO 2. Construct oblique drawing Direction: Given three orthographic views, draw the cabinet drawing at 300

depth axis.

9 30

RIGHT SIDE VIEW

TOP VIEW

50

16

12

30

50

15

FRONT VIEW

20


Unit of Competency : CONSTRUCT PERSPECTIVE DRAWING


Learning Outcome 3: Construct perspective drawing

Assesment Criteria

1. Principles of perspective drawing are discussed.

2. Three types of perspective drawing are identified and differentiated.

3. Each type of perspective drawing is constructed according to

specifications.

References:


Company: 1949.


editon: 1960



1977

21


Learning Outcome # 3: Construct Perspective Drawing


1, Read the attached information

sheet no. 3 about perspective

drawing.

2. Do operation sheet no. 3.1

(One-Point Perspective

Drawing) 3.2.(Two- Point

Perspective Drawing) and 3.3

(Mechanical method in

drawing angular or two-point

perspective).

3. Answer the self check no. 3.1.

then compare your answer

with the answer key.


sheet no. 3.1 and 3.2 for self

checking.

o Try to answer the self check

within the least possible time

allotment.

22


LO3. Construct perspective drawing

Perspective Drawing is a pictorial drawing which contains receding

lines that converge at vanishing points on the horizon. This drawing is also

called as “foreshortened drawing”.

Principles of Perspective Drawing:

1. All receding lines converge on a vanishing points.

2. The farther the color, the lighter it appears.

3. The farther the object, lines, edges, the smaller it appears.

4. The object can be viewed in terms of bird’s eye view, eye level,

and ants view. (see figure 1, 2, 3).

5. The vanishing point can be located anywhere as long as the

object will not be distorted. For the two-point perspective, the

two vanishing points must be aligned to each other.

Fig.3. Ant’s Eye View or Worm’s Eye View Fig.2. Man’s Eye View or Eye level View Fig.1. Bird’s Eye View

23

Types of Perspective Drawing

1. One-point or parallel perspective – is a receding line that

converges on a single vanishing point.

2. Two-point or angular perspective – is a receding line that

converges on two vanishing points.

3. Three-point perspective – is a receding line that converges on

three vanishing points.

TECHNICAL TERMS:

Picture Plane (PP) . This is an imaginary vertical plane where the picture is

registered.

Ground Line (GL) .This is where the actual figure is laid.

Station Point (SP) . This is the fixed position where the object is actually

viewed.

Visual Rays. These are imaginary lines projecting from the observer to the

figure passing through the picture plane. They are sometimes called receding

lines.

Horizon (H) . This is the point where the figure appears horizontally at eye

level.

Vanishing Point (VP) . This is the point where all receding lines meet in a

perspective figure.

24


LO3. Construct perspective drawing Procedure in Constructing One-Point Perspectives or Parallel Perspective.

1. Draw top and front view, picture plane, horizon line and ground line

TOP VIEW

FRONT VIEW

PICTURE PLANE

HORIZON LINE

GROUND LINE

25

2. Locate station point and project lines of visual rays from the

corners of the top view to station point.

TOP VIEW

FRONT VIEW

HORIZON LINE

STATION POINT

26

3. Project vertically from station point for single vanishing point.

TOP VIEW

STATION POINT

PICTURE PLANE

VANISHING POINT

GROUND LINE

HORIZON LINE

27

4. Project corners to the vanishing point.

TOP VIEW

FRONT VIEW

HORIZON LINE

PICTURE PLANE

STATION POINT

VANISHING POINT

GROUND LINE

28

5. Drop projectors at picture plane to determine depths and

completeness.

TOP VIEW

PARALLEL PERSPECTIVE

PICTURE PLANE

STATION POINT

VANISHING POINT

GROUND LINE

HORIZON

29



Procedure in Constructing Two-Point Perspective or Angular Perspective

1. Estimate location of horizon, vanishing points and leading

corners of the objects.

2. Get the height of the object and project the upper and lower

vanishing lines to the vanishing points.

HEIGHT OF THE OBJECT

LOWER VANISHING LINES

UPPER VANISHING LINES

RVP LVP

30

3. Estimate the width and length.

4. Complete the construction box by projecting the two

intersecting

points between vanishing lines and vertical lines.

5. Estimate position of features towards the vanishing points.

RVP

INTERSECTING

POINTS

RVP

LVP

LVP

31

6. Connect intersecting lines.

7. Complete drawing. Add shading if desired and finally erase the

construction lines.

32



Mechanical procedures in drawing Angular or Two-Point Perspective:

0

SP

1. Using T-square, draw the picture plane (PP). From PP, draw the top

view of an object in oblique position at 300 and 600 (vice-versa) of its

sides using 30O x 600 triangle.

2. Draw a vertical line along center-edge of the top view to locate the

station point (SP) at a distance of not less than twice the scales length

of an object. From station point, project a line along all corners of the

top view. Mark a point as a piercing point on the picture plane.

3. From station point (SP), project a line right 300 cross axis and left 600

cross axis (vice-versa) touching the picture plane.

HORIZON RVP LVP

600 300

PLAN

PERSPECTIVE FRONT VIEW RIGHT SIDE VIEW GROUND LINE

PICTURE PLANE

33

4. Establish a ground line. Draw the front and side views of the object at

the right or left side of the ground line.

5. Locate the horizon between the picture plane (PP) and ground line

(GL).

6. From Step-2 at piercing points on the picture plane, project vertical

lines along horizon line to establish the left and right vanishing

points.

7. From piercing points in the picture plane (PP), project vertical lines

along the ground line to create all measuring lines of width & depth.

8. Project horizontally all the heights of the front view and side view

along measuring lines of width and depth respectively.

9. Connect all corner horizontal heights to LVP and RVP to complete the

perspective drawing.

10. Finalize the drawing.

34

SELF CHECK # 3.1


Direction: Given the three orthographic views, draw the parallel perspective

drawing.

5

RIGHT SIDE VIEW

TOP VIEW

40

12

16

10

30

40

10 10

FRONT VIEW

35

SELF CHECK # 3.2


Direction: Given the three orthographic views, draw the angular perspective

drawing.

RIGHT SIDE VIEW

TOP VIEW

40

12

16

10

30

40

10 10

FRONT VIEW

36


Written Test LO1. Construct Isometric Drawing

LO2. Construct Oblique Drawing

LO3. Construct Perspective Drawing

I. Identification. Write the correct answer on the blanks.

____________________________1. A type of drawing that shows the width,

and height of an object.

____________________________2. A pictorial drawing which shows the front,

side and top faces of an object in one view

the receding lines are always parallel.

____________________________3. A type of pictorial drawing wherein all

receding angles are 30 degrees.


receding angles are 15 degrees and the

other is 45 degrees.


receding

___________________________6. A pictorial drawing in which the front plane

is parallel to the plane of projection.

______________________________7. A type of oblique drawing which is prepared

to it’s actual measurement.

___________________________8. A type of oblique drawing in which the

the thickness of the object is reduced

by half.

___________________________9. A pictorial drawing which contains receding

lines that converge at a vanishing points

on the horizon.

___________________________10. A closed curve in the form of a symmetrical

oval.

Enumeration

Enumerate at least two principles for each of the following:

1. Isometric Drawing

2. Oblique Drawing

3. Perspective Drawing

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ANSWER KEY

I. 1.Pictorial Drawing

3. Axonometric Drawing

4. Isometric Drawing

5. Dimetric Drawing

6. Trimetric Drawing

7. Oblique Drawing

8. Cavalier oblique

9. Cabinet Oblique

10. Perspective Drawing

11. Ellipse

II.

1. Principles of Axonometric Drawing

o The drawing shows all three faces of an object.

o The receding lines are always parallel.

2. Principles of Oblique Drawing

o The longest measurement should be placed in front.

o Irregular shapes of the object should be placed in front to

minimize distortion.

o Circles and circular arcs should be placed in front to minimize

distortion.

3. Principle of Perspective Drawing

o All receding lines converge on vanishing points.

o The farther the object, the smaller it appears.

o The farther the object, the lighter it appears.

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Scoring Rubrics


Accuracy

50

45

40

Speed

10

6

8

Neatness

25

20

15

Lettering/Labeling

15

12

10

8

Total





Speed




Neatness

25 pts. - has no error

20 pts - has two to three erasures

15 pts - has four or more erasures

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Lettering/Labeling

15 pts. - All pieces of information are completely indicated and

legibly printed.


missing.


missing and misspelled.

8 pts. - Pieces of information are not legibly printed and words are

misspelled.

technical drawing y1

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