GE ENGINEERING GRAPHICS

Transcription

1 ANNA UNIVERSITY, CHENNAI (REGULATION GE ENGINEERING GRAPHICS B.E SEMESTER I Lecture Tutorial Practical Marks Credits Total Hours Mr.S.Gokul (Asst. Prof/Mech) Sri Eshwar College of Engineering

2 2 Unit 1 Unit 2 Unit 3 Unit 4 Unit 5 Syllabus Frame 1. Engineering Curves 2. Free hand sketching of Objects PLANE CURVES AND FREE HAND SKETCHING 1. Projection of Points 2. Projection of Lines PROJECTION OF POINTS, 3. Projection LINES of Planes AND PLANE SURFACES Projection of simple PROJECTION OF SOLIDS solids like, prism, pyramid., 1. Section of Solids 2. Development of PROJECTION OF SECTIONED SOLIDS AND DEVELOPMENT OF Solids 1. Isometric SURFACES projection 2. Perspective ISOMETRIC AND PERSPECTIVE projection PROJECTIONS

3 3 TEXT BOOKS Natrajan K.V., A text book of Engineering Graphics, Dhanalakshmi Publishers, Chennai, REFERENCES Venugopal K. and Prabhu Raja V., Engineering Graphics, New Age, International (P) Limited, Kottiswaran N.,, Sri Balaji Publications, Saravanan.M, Arockia Jaswin.M and Bensam Raj J.,,Tri Sea Publications.

4 COURSE PLAN 4 Title of the program: B.E Course title: ENGINEERING GRAPHICS Sem: I Course code: GE 8152 Total hours: 90 Unit No. Unit Title Time 1 PLANE CURVES AND FREE HAND SKETCHING 19 2 PROJECTION OF POINTS, LINES AND PLANE SURFACES 3 PROJECTION OF SOLIDS 16 4 PROJECTION OF SECTIONED SOLIDS AND DEVELOPMENT OF SURFACES 5 ISOMETRIC AND PERSPECTIVE PROJECTIONS Revision 5 Total 90

5 Content of the Presentation 5 Introduction to Standards (BIS) Drawing Instruments Lettering Line types Dimensioning Projection Methods Quadrant system Introduction to all the units

6 INTRODUCTION TO ENGINEERING GRAPHICS

7 Drawing vs. Engineering Drawing 7 Drawing Describing any object/ information diagrammatically Engineering Drawing Graphical means of expression of technical details without the barrier of a language. Universal language for engineers

8 Drawing vs. Engineering Drawing Cont., 8 Graphical representation of an object Drawing Engineering drawing A drawing of an object that contains all information - like actual shape, accurate size, manufacturing methods, etc., required for its construction. - No construction / manufacturing of any (man -made) engineering objects is possible without engineering drawing.

9 What will you learn in this course? 9 You will learn - How industry communicates technical information. Visualization the ability to mentally control visual information. Graphics theory geometry and projection techniques. Standards set of rules that govern how parts are made and technical drawings are represented.

10 What will you learn in this course? Cont., 10 Conventions commonly accepted practices and methods used for technical drawings. Tools devices used to create technical drawings and models. Applications the various uses for technical drawings.

11 11 Engineering drawing is completely different from artistic drawing, which are used to express aesthetic, philosophical, and abstract ideas. Engineering Drawing Manual Drawing CADD Computer has a major impact on the methods used to design and create technical drawings. Design and drafting on computer are cheap and less time consuming.

12 STANDARDS

13 Standard Code Country Code Full name USA Japan UK Australia Germany India ANSI JIS BS AS DIN BIS American National Standard Institute Japanese Industrial Standard British Standard Australian Standard Deutsches Institute for Normung Bureau of Indian Standards ISO 13 International Standards Organization

14 BIS standards 14 BIS Code IS 10711:2001 IS 10714:1983 IS 9609:2001 IS 15021:2001 IS 11669:1986 Topics Size and Layout of Drawing sheets Line Types and Uses Lettering Projection Methods Dimensioning

15 DRAWING INSTRUMENTS

16 Instruments required for drawing 16 Drawing board Drawing sheet [A3 Size] Mini-drafter / T- square Instrument box (Compass, Divider, Protractor etc.,) Drawing pencils [H, 2H, HB] Scales, Sharpener, Eraser Drawing clip / pin / adhesive tape

17 1.Drawing Board 17

18 2.Drawing Sheets 18 A Series Formats (mm) A A A A A A A A

19 Drawing Sheets cont., 19 A Series Formats (mm) A A A A A A A A

20 c c Orientation of drawing sheet 1. Type X (A0~A4) 2. Type Y (A4 only) d Border lines d Drawing space c Title block Drawing space Title block Sheet size c (min) d (min) A A A A A0 Engineering 20 Graphics 25

21 A3 Drawing sheet - Dimensions 21

22 3. Mini Drafter and T-Square 22

23 Drawing Board with Drafter and Sheet 23

24 4. Instrument Box 24

25 5.Drawing Pencils 25 Wooden pencils are graded and designated by numbers and letters Mechanical clutch pencils Not allowed 7B, 6B, 5B, 4B, 3B, 2B, B - in decreasing order of softness and blackness HB to F Medium grade H, 2H, 3H, 4H, 5H, 6H, 7H, 8H, 9H increasing order of hardness. Drawings are done using 2H pencils and finished with H and HB pencils to be practiced in this course.

26 Grades and designation of wooden pencils 26

27 Grades and designation of wooden pencils 27

28 6.Scales, Sharpener, Eraser 28

29 7.Drawing clip / pin / adhesive tape 29

30 DRAWING SCALES

31 Drawing Scales Length, size Scale is the ratio of the linear dimension of an element of an object shown in the drawing to the real linear dimension of the same element of the object. Size in drawing Actual size : 31

32 Drawing Scales Designation of a scale consists of the word SCALE followed by the indication of its ratio, as follow SCALE 1:1 for full size SCALE X:1 for enlargement scales (X > 1) SCALE 1:X for reduction scales (X > 1) Dimension numbers shown in the drawing are correspond to true size of the object and they are independent of the scale used in creating that drawing. 32

33 LINE TYPES

34 Line types 34

35 Line types cont., 35

36 DIMENSIONING

37 Lines used in Dimensioning 37 Dimensioning requires the use of Dimension lines Extension lines Leader lines All three line types are drawn thin so that they will not be confused with visible lines.

38 Dimension Line 38 Dimension line: A line terminated by arrowheads, which indicates the direction and extent of a dimension.

39 Extension Line 39 Extension line: An extension line is a thin solid line that extends from a point on the drawing to which the dimension refers. Long extension lines should be avoided.

40 Leader Line 40 Leader Line: A straight inclined thin solid line that is usually terminated by an arrowhead.

41 Leader Line 41 Leaders may be terminated: with an arrow, if it ends on the outline of an object.

42 Leader Line 42 Leaders may be terminated: with a dot if it ends within the outline of an object.

43 Leader Line 43 Leaders may be terminated: without an arrowhead or dot, if it ends within the outline of an object.

44 Arrow heads 44 Arrowheads are used as terminators on dimension lines. The standard size ratio for all arrowheads on mechanical drawings is 3:1 (length to width). 200 R 8.5 Of the four different arrowhead types that are authorized by the national standard, ASME Y14.2M 1994, a filled arrowhead is the highest preference. 1st 2nd 3rd 4th

45 Arrowheads 45 Arrowheads are drawn between the extension lines if possible. If space is limited, they may be drawn on the outside.

46 Exercise 46 List the dimensioning mistakes and then dimension the object correctly.

47 What are the 6 dimensioning mistakes?

48 1) Spacing 2) Don t dim. inside the object. 3 & 4) Text 5) No Gap 6) Missing dim. (ɸ of hole)

49 Correctly Dimensioned

50 LETTERING

51 Lettering 51 Lettering Writing of titles, sub-titles, dimensions, scales and other details on a drawing Essential features of lettering legibility, uniformity, ease, rapidity, and suitability for microfilming/ photocopying/any other photographic processes No ornamental and embellishing style of letter Plain letters and numerals which are clearly distinguishable from each other in order to avoid any confusion even in case of slight mutilations

52 Basic Strokes 52 Straight Slanted Horizontal Curved Examples : Application of basic stroke I letter A letter B letter

53 Lettering cont., 53

54 Stroke Sequence 54 I L T

55 Stroke Sequence 55 V X W

56 Stroke Sequence 56 O Q G

57 Stroke Sequence 57 S

58 Stroke Sequence j y f t r 58

59 Stroke Sequence c o a b d p q e 59

60 Sentence Composition Leave the space between words equal to the space requires for writing a letter O. Example ALL ODIMENSIONS OAREOIN MILLIMETERS OTHERWISE OUNLESS OSPECIFIED. 60

61 PROJECTION METHODS

62 Line of sight is an imaginary ray of light between an observer s eye and an object. There are 2 types of LOS : parallel and converge Parallel projection Line of sight Perspective projection Line of sight 62

63 63 PROJECTION METHOD Perspective Parallel Oblique Orthographic Axonometric Multiview

64 PROJECTION THEORY The projection theory is used to graphically represent 3-D objects on 2-D media (paper, computer screen). The projection theory is based on two variables: 1) Line of sight 2) Plane of projection (image plane or picture plane) 64

65 Plane of projection is an imaginary flat plane which the image is created. The image is produced by connecting the points where the LOS pierce the projection plane. Parallel projection Plane of projection Perspective projection Plane of projection 65

66 66 Disadvantage of Perspective Projection Perspective projection is not used by engineer for manufacturing of parts, because 1) It is difficult to create. 2) It does not reveal exact shape and size. Width is distorted

67 QUADRANT SYSTEM

68 2 nd Quad. VP 1 ST Quad. Y Observer X Y HP X 3 rd Quad. 4 th Quad. THIS QUADRANT PATTERN, IF OBSERVED ALONG X-Y LINE ( IN RED ARROW DIRECTION) WILL EXACTLY APPEAR AS SHOWN ON RIGHT SIDE AND HENCE, 68IT IS FURTHER USED TO UNDERSTAND Engineering ILLUSTRATION Graphics PROPERLLY.

69 First angle vs. Third angle Projection 69 First angle Projection Object placed in FQ is above HP and in front of VP Front view is draw above reference line Top view is arranged below FV Left side view is on the right side of FV and Right view is on the left side of FV Symbol Third angle Projection Object placed in TQ is below HP and behind of VP Front view is draw below reference line Top view is arranged above FV Left side view is on the left side of FV and Right view is on the right side of FV Symbol

70 INTRODUCTION TO ALL THE UNITS

71 71 Unit 1 PLANE CURVES AND FREE HAND SKETCHING

72 PLANE CURVES AND FREE HAND SKETCHING 72 Engineering Curves Ellipse Parabola Hyperbola Special Curves Cycloids Epicycloid Hypocycloid Involutes

73 73 PLANE CURVES AND FREE HAND SKETCHING Free hand sketching

74 74 Unit II PROJECTION OF POINTS, LINES AND PLANE SURFACES

75 Point A is Placed In different quadrants and it s Fv & Tv are brought in same plane for Observer to see clearly. Fv is visible as it is a view on VP. But as Tv is is a view on Hp, it is rotated downward 90 0, In clockwise direction.the In front part of Hp comes below xy line and the part behind Vp comes above. POINT A IN 2 ND QUADRANT A HP HP VP a a a OBSERVER OBSERVER VP a a A POINT A IN 1 ST QUADRANT HP HP OBSERVER OBSERVER Observe and note the process. A POINT A IN 3 RD QUADRANT VP a a a VP A POINT A IN 4 TH QUADRANT 75 PROJECTION OF POINTS

76 PROJECTIONS OF A POINT IN FIRST QUADRANT. POINT A ABOVE HP & INFRONT OF VP For Tv POINT A ABOVE HP & IN VP For Tv POINT A IN HP & INFRONT OF VP a PICTORIAL PRESENTATION a A PICTORIAL PRESENTATION For Tv Y A a Y a Y X a X X A a ORTHOGRAPHIC PRESENTATIONS OF ALL ABOVE CASES. Fv above xy, Tv below xy. VP a Fv above xy, Tv on xy. VP a Fv on xy, Tv below xy. VP X Y X a Y X Y a a a 76 HP HP HP

77 (Pictorial Presentation) 1. A Line perpendicular to Hp & // to Vp X a FV b For Tv A Y B TV a b Note: Fv is a vertical line Showing True Length & Tv is a point. X Orthographic Pattern V.P. a Fv Tv b a b Y (Pictorial Presentation) 2. A Line // to Hp & // to Vp X a A b a For Tv Y B b Note: Fv & Tv both are // to xy & both show T. L. 77 PROJECTION OF LINES X H.P. Orthographic Pattern V.P. a a Fv b H.P. Tv b Y

78 78 PROJECTION OF POINTS, LINES AND PLANE SURFACES PROJECTION OF PLANE SURFACES

79 79 Unit III PROJECTION OF SOLIDS

80 PROJECTION OF SOLIDS 80

81 81 Unit IV PROJECTION OF SECTIONED SOLIDS AND DEVELOPMENT OF SURFACES

82 SECTION OF SOLIDS 82

83 DEVELOPMENT OF SOLIDS 83

84 84 Unit V ISOMETRIC AND PERSPECTIVE PROJECTIONS

85 ISOMETRIC PROJECTIONS 85

86 PERSPECTIVE PROJECTIONS 86

87 Thank You 87

88 Sri Eshwar College of Engineering Department of Mechanical Engineering GE ENGINEERING GRAPHICS OBJECTIVES: To develop in students, graphic skills for communication of concepts, ideas and design of Engineering products. To expose them to existing national standards related to technical drawings. CONCEPTS AND CONVENTIONS (Not for Examination) Importance of graphics in engineering applications Use of drafting instruments BIS conventions and specifications Size, layout and folding of drawing sheets Lettering and dimensioning. UNIT I PLANE CURVES AND FREE HAND SKETCHING Basic Geometrical constructions, Curves used in engineering practices: Conics Construction of ellipse, parabola and hyperbola by eccentricity method Construction of cycloid construction of involutes of square and circle Drawing of tangents and normal to the above curves, Scales: Construction of Diagonal and Vernier scales. Visualization concepts and Free Hand sketching: Visualization principles Representation of Three Dimensional objects Layout of views- Free hand sketching of multiple views from pictorial views of objects UNIT II PROJECTION OF POINTS, LINES AND PLANE SURFACES Orthographic projection- principles-principal planes-first angle projection-projection of points. Projection of straight lines (only First angle projections) inclined to both the principal planes - Determination of true lengths and true inclinations by rotating line method and traces Projection of planes (polygonal and circular surfaces) inclined to both the principal planes by rotating object method UNIT III PROJECTION OF SOLIDS Projection of simple solids like prisms, pyramids, cylinder, cone and truncated solids when the axis is inclined to one of the principal planes by rotating object method. UNIT IV PROJECTION OF SECTIONED SOLIDS AND DEVELOPMENT OF SURFACES Sectioning of above solids in simple vertical position when the cutting plane is inclined to the one of the principal planes and perpendicular to the other obtaining true shape of section. Development of lateral surfaces of simple and sectioned solids Prisms, pyramids cylinders and cones. UNIT V ISOMETRIC AND PERSPECTIVE PROJECTIONS Principles of isometric projection isometric scale Isometric projections of simple solids and truncated solids - Prisms, pyramids, cylinders, cones- combination of two solid objects in simple vertical positions. Perspective projection of simple solids-prisms, pyramids and cylinders by visual ray method. Unit No. Topics Page No. 1 Plane Curves and Free Hand Sketching. 10 Engineering Curves: Ellipse, Parabola & Hyperbola 10 Construction of Cycloid 10 Construction of Involutes 10 Scale : Diagonal and Vernier scales 10 Free Hand Sketching 11 Plane Curves & Free Hand Sketching Assignment Projection of Points, Lines and Plane Surfaces... Orthographic Projection of Points 2 Orthographic Projection of Straight Lines 2 Projection of Straight Lines Assignment 1 3 Orthographic Projection of Planes 3 Orthographic Projection of Planes Assignment Projection of Solid. 4 Orthographic Projection of Solids 4 Truncated Solids 6 Orthographic Projection of Solids Assignment Projection of Sectioned Solids and Development of Surfaces Section of Solids 5 Development of Surface 6 Sectioned Solids & Development of Surfaces 7 Assignment 4 5 Isometric and Perspective Projections.. 7 Isometric Projection 7 Perspective Projection 8 Isometric & Perspective Projections 9 Assignment Mr.S.Gokul/Assistant Professor/Department of Mechanical Engineering

89 Mr.S.Gokul/Assistant Professor/Department of Mechanical Engineering UNIT II - PROJECTION OF POINTS, LINES AND PLANE SURFACES Projection of point Projection of straight lines inclined to both the principal planes by rotating line method and traces Projection of planes (polygonal and circular surfaces) inclined to both the principal planes by rotating object method Orthographic Projection of Points 1. Mark the projections of the following points on a common reference line. Point P, 50 mm behind the VP and 15 mm above the HP. Point Q, 40 mm below the HP and in the VP. Point R, 40 mm in front of the VP and 30 mm above the HP. Point S, 30 mm in front of the VP and 50 mm below the HP. Point T, 35 mm behind the VP and 20 mm below the HP. 2. From the figure below, determine the position of the Points with reference to the projection planes. Orthographic Projection of Straight Lines 1. One end P of a line PQ 70 mm long is 35 mm in front of V.P. and 25 mm above H.P. the line is inclined at 40 0 to the H.P. and 30 0 to the V.P. Draw the projections of PQ and find its vertical & Horizontal trace 2. A straight line 70 mm long has one end 15 mm in front of V.P. and 50 mm above H.P. while the other end is 35 mm in front of V.P. and 20 mm above HP. Draw the plan and elevation of the line. Determine its traces (V.T, H.T) 3. A line AB 70 mm long has its end B 25 mm above H.P. and 30 mm in front of V.P. The end A is 55 mm above H.P and 55 mm in front of V.P. Draw its projections and finds its inclinations with V.P. and H.P. 4. A line AB 60 mm long has its end A 30 mm above H.P. and 25 mm in front of V.P. The top view and front view has a length of 40 mm and 55 mm respectively. Draw its projections. 5. End A of a line AB is 15 mm above H.P. and 20 mm in front of V.P. The other end is 50 mm above H.P. and 65 mm in front of V.P. The distance between the end projectors is 50 mm. Draw the projection and find the true inclination and true length by rotating plane method. 6. The distance between the end projectors passing through the end point is 50 mm. The end A is 20 mm above H.P. and 15 mm in front of V.P. The end B is 45 mm in front of V.P. The line AB is 65 mm long in the front view. Draw the projections. Find the true inclinations and locate the traces 7. Front view of a line AB is 50 0 inclined to XY line and measures 55 mm long while its top view is 60 0 inclined to XY line. If end A is 10 mm above HP and 15 mm in front of VP, draw its projections, find its true length and inclinations of the line with HP and VP. 8. The mid-point M of a line AB is 60 mm above HP and 50 mm in front of VP. The line measures 80 mm long and inclined at an angle of 30 0 to HP and 45 0 to VP. Draw its projections.

90 GE A magician performs the trick of a floating stick. As seen by a person sitting right in front, as per the orthographic projection rules, the stick has its ends 0.2 and 0.6 m above the floor and appears to be inclined at 30 0 to the floor. The same two ends are found to be 0.1 m and 0.7 m respectively in front of the screen arranged behind the stick. Adopting a suitable scale, draw the projections of the stick. Also, find the true length of the stick and its true angles of inclinations with the floor and the vertical screen. 10. A line PQ is inclined at 35 0 to VP has its ends 25mm and 55mm above the HP. The length of the front view is 60 mm and its VT is 15mm above HP. Determine the true length of PQ, its inclination with HP and its HT. Assignment 1: Orthographic Projection of Straight Lines L1. A line AB 75 mm long has one of its ends 60 mm in front of VP and 20 mm above HP, the other end is 20 mm in front of VP and is above HP. The top view of the line is 55 mm long. Draw the front view. L2. A line measuring 80 mm long has one of its ends 60 mm above HP and 20 mm in front of VP. The other end is 15 mm above HP and in front of VP. The front view of the line is 60 mm long. Draw the top view. L3. A line AB has its end A 15 mm above HP and 20 mm in front of VP. The end B is 60 mm above HP and the line is inclined at 30 0 to HP. The distance between the end projectors of the line is 55 mm. Draw the projections and find its inclinations with VP. Determine its V.T & H.T L4. The top view of a 75mm long line AB measures 65mm, while the length of its front view is 50mm. It s one end A is in the HP and 122mm in front of the V.P. Draw the projections of AB and determine its inclinations with the H.P. and the V.P. L5. The projections of a line measure 80 mm in the top view and 70 mm in the front view. The mid-point of the line is 45 mm in front of VP and 35 mm above HP. One end is 10 mm in front of VP and nearer to it. Draw the projections. Find true length and true inclinations with reference planes. Department of Mechanical Engineering, Sri Eshwar College of Engg Orthographic Projection of Planes / Sheet / Lamina / Plate 1. A square lamina of 50 mm side rests on one of the corners on the H.P. The diagonal through that corner makes 30 0 to the V.P. The side containing this corner makes equal inclinations with H.P. The surface of the lamina makes 45 0 to the H.P. Draw it s projections. 2. A hexagonal plate of size 25 mm rests on HP on one of the sides inclined at 45 0 to VP. The surface of the plate makes an angle of 30 0 with HP. Draw the front view and top view of the plate. 3. A thin rectangular plate of sides 60 mm x 30 mm has its shorter side in VP and inclined at 30 0 to HP. Project its top view when its front view is a square of 30 mm long sides. 4. A hexagonal lamina of 20 mm side rests on one of its corners on the HP. The diagonal passing through this corner is inclined at 45 0 to the HP. The lamina is then rotated through 90 0 such that the top view of this diagonal is perpendicular to the VP and the surface is still inclined at 45 0 to the HP. 5. A pentagon of side 30 mm rests on the ground on one of the corners with sides containing the corner being equally inclined to the ground. The side opposite to the corner on which it rests is inclined at 30 0 to VP and is parallel to HP. The surface of the pentagon makes 50 0 with the ground. Draw the projections of the pentagon. 6. A semicircular lamina of 60 mm diameter has its straight edge in VP and inclined at an angle of 45 0 to HP. The surface of the lamina makes an angle of 30 0 with VP. Draw the projections. 7. A circular lamina of 50 mm diameter rests above HP on a point P on its circumference. If its plane is inclined at 45 0 to HP and the top view of the diameter PQ makes an angle of 50 0 with VP, draw the projections of the lamina. 8. A circular lamina of diameter 70 mm has the end A of the diameter AB on HP and B on VP. Draw its projections when its surface is inclined at 50 0 to HP and 40 0 to VP. 3/12

91 GE 6152 Assignment 2: Orthographic Projection of Planes P6. A square ABCD of 40 mm side has its plane inclined at 30 0 to the V.P. It s one side is inclined at 60 0 to the H.P. and parallel to the V.P. Draw its projections. P7. A rhombus of diagonals 25mm and 15mm with longer diagonal being parallel to XY-line represents the top view of a square of diagonal 25mm, with a corner on H.P. Draw its front view of the lamina when the edge about which is tilted, is inclined at 45 0 to V.P P8. A thin set-square has its longest edge in V.P. and inclined at 30 0 to H.P. Its surface makes 45 0 with V.P. Draw its projections. P9. A hexagonal plate of 25 mm side is resting on H.P. such that one of its corners touches both H.P. and V.P. It makes 30 0 with H.P. and 60 0 with V.P. Draw the projections by change of position method. P10. A circular lamina of 60 mm diameter rests on H.P. on a point 1 on the circumference. The lamina is inclined to H.P. such that the top view of it is an ellipse of minor axis 35 mm. The top view of the diameter through the point 1 makes an angle of 45 0 with V.P. (i) Draw the projections. (ii) Determine the angle made by the lamina with H.P. UNIT III - PROJECTION OF SOLID Projection of simple solids by rotating object method Orthographic Projection of Solids 1. A hexagonal prism of base side 25 mm and axis height 55 mm resting on HP with one of its base edges, such that, the axis is inclined at 30 0 to HP and parallel to VP. Draw the projections of the prism. 2. A pentagonal prism of base side 25 mm and height 55 mm is resting on HP with one of its base edges, such that the lateral surface containing the edge is inclined at 50 0 to HP and perpendicular to VP. Draw the projections. 3. A right pentagonal pyramid of side 20 mm and altitude 50 mm rests on one of its edges of the base in the HP. The base being tilted up such that the apex is 30 mm above HP. Draw the projection of the pyramid when the edge on which it is resting is perpendicular to VP 4. A cylinder of diameter 35 mm and axis height 55 mm is resting on the ground on its base. It is then tilted such that a solid diagonal is vertical. Draw its projections. 5. A cone of diameter 35 mm and height 55 mm is lying on the ground with a point of base on HP. The generator line passing through that point makes an angle of 45 0 with HP and parallel to VP. Draw its projections. 6. Draw the projections of a pentagonal pyramid of base side 25 mm and axis height 60 mm with a triangular face perpendicular to HP and VP. 7. A hexagonal prism of base side 30mm and axis length 60mm rests on the HP on one of the base corners with the base edges containing it being equally inclined to HP. The axis is inclined at 45 to the HP and parallel to VP. Draw the projections of the prism. 8. A cone of diameter 35mm, height 55mm is lying on the ground with one of its generators parallel to VP and on the HP. Draw its projection. 9. A pentagonal prism of base side 25 mm and axis length 55 mm is resting on HP on one of its rectangular faces with the axis inclined at 45 0 to VP. Draw its projections. 10. A cone of diameter 40mm and height 60mm is freely suspended from one of its base points such that the axis is parallel to VP. Draw the projection. 11. A tetrahedron of edges 35 mm rests on one of its edges on the HP. The resting edge is perpendicular to VP and one of the triangular faces containing the resting edge is inclined at 35 0 to HP. Draw the projections of the tetrahedron. 12. A tetrahedron of side 45 mm is resting on an edge on the HP such that the face containing that edge is seen as a triangle of base 45 mm and altitude 25 mm in top view (TV). The axis of the tetrahedron is parallel to the VP. Draw the projections of the tetrahedron. 4/12 Department of Mechanical Engineering, Sri Eshwar College of Engg

92 GE 8152 Assignment 3: Orthographic Projection of Solids S1. Draw the top front views of a right circular cylinder of base 45mm diameter and 60mm long when it line on HP, such that its axis is inclined at 30 to HP and the axis appears to parallel to the VP in the top view S2. Draw the projections of a pentagonal pyramid of base side 25 mm and axis height 60 mm with a slant edge perpendicular to HP and VP. S3. A cone of base diameter 35 mm and axis length 55 mm is resting on HP on a point on circumference of the base. Draw the projections when the base is perpendicular to both HP and VP. S4. A pyramid has rectangular base of size 70 mm x 40 mm and height 85 mm. Its longer edge of base is perpendicular to HP. The axis of pyramid is inclined at 25 0 to the solid assuming the apex nearer to the observer. S5. Draw the projections of a cube of side 30mm when it rests on one of its corners with diagonal of the solid vertical S6. A tetrahedron of edges 30 mm rests on one of its edges on the VP. That edge is normal to the HP. One of the faces containing the resting edge is inclined at 30 to the VP. Draw the projections of the tetrahedron S7. A Hexagonal prism, side of base 25 mm and axis 50mm long is freely suspended from one of its base corners, such that the axis is parallel to VP. Draw the front view and top view of the solid in the above position. UNIT IV - PROJECTION OF SECTIONED SOLIDS AND DEVELOPMENT OF SURFACES Sectioning of solids to obtain true shape of section. Development of lateral surfaces of simple, sectioned solids and solids with cut-outs and holes Section of Solids 1. A cube of side 35 mm is placed on HP on a face, with two of the vertical faces equally inclined to VP. It is cut by a plane inclined at 54 0 to the HP and bisecting the axis. Draw the sectional top view and find the true shape. 2. A pentagonal pyramid of base side 25 mm and altitude 50 mm rests on its base on HP with one of the base edges perpendicular to the VP. It is cut by a plane inclined at 45 0 to the base. The cutting plane meets the axis at 20 mm above the base. Draw the front view, sectional top view and true shape of the section. 3. A cylinder of base diameter 35 mm and height 55 mm rests on its base on HP. It is cut by a plane perpendicular to VP and inclined at 45 0 to HP. The cutting plane meets the axis at a distance of 15 mm from the top base. Draw the sectional plan and true shape of the section. 4. A cone of base diameter 35 mm and altitude 55 mm is resting on HP on its base. It is cut by a plane perpendicular to VP and parallel to a contour generator and is 10 mm away from it. Draw the front view and sectional top view and true shape of the section. 5. A hexagonal prism of base side 25 mm and height 50 mm rests on the HP on one of its ends with two rectangular faces parallel to the VP. It is cut by a plane perpendicular to the HP and inclined at 50 0 to the VP. It is cut by a plane perpendicular to HP and inclined at 50 0 to VP at a distance of 10 mm away from the axis. Draw the top view, sectional front view and true shape of the section. Department of Mechanical Engineering, Sri Eshwar College of Engg 5/12

93 GE A right circular cone of base diameter 40 mm and axis length 50 mm rests on its base on HP. It is cut by a plane perpendicular to the HP and inclined at 55 0 to the VP. The shortest distance between the cutting plane and the top view of the axis is 10 mm. Draw the top view, sectional front view and true shape of the section. 7. A pentagonal prism of base side 40 mm and axis length 80 mm is lying on the HP on one of its rectangular faces with the axis parallel to both HP and VP. It is cut by a plane perpendicular to HP and inclined at 30 0 to VP. The section plane meets the axis at 16 mm from one of its ends. Draw the top view, sectional front view and true shape of the section. 8. A tetrahedron of side 60mm is resting on HP on one of its faces. It is cut by a plane perpendicular to the VP, so that the true shape of the cut section is a triangle of base 40mm and altitude 30mm. Locate the plane and determine the angle of inclination of the VT with the reference line XY. Draw the sectional top view and true shape of the section. Development of Surface 1. Draw the development of a cube of side 20 mm. 2. Draw the development of a pentagonal prism of side 25 mm and height 60mm. 3. Draw the development of a cylinder of base diameter 25 mm and height 30 mm. 4. Draw the development of a square pyramid of base side 30 mm and height 45 mm. 5. Draw the development of a cone of base diameter 50 mm and height 60 mm. 6. Draw the development of a cube of side 40 mm resting on its face with all the edges equally inclined to VP, which is cut by a plane inclined at 30 0 to HP and perpendicular to VP and passing through the cube at the top left corner of the cube. 7. A square pyramid of base side 30 mm and height 50 mm rests on its base on HP, with a base edge parallel to VP. It is cut by a plane perpendicular to VP, 50 0 to HP meeting the axis 30 mm above HP. Draw the development of the lateral surfaces. 8. A lamp shade is formed by cutting a cone of base diameter 144 mm and height 174 mm by a horizontal plane at a distance of 72 mm from the apex and another plane inclined at 30 to HP, passing through one of the extremities of the base. Draw the development of the shade. Draw the development of the shade. Adopt a suitable scale. 9. A pentagonal prism of base side 30 mm and height 60 mm is cut by a plane perpendicular to VP and 50 0 to HP and passing through the axis 35 mm above the base. Draw the development of the lower portion of the solid. 10. A cylinder of diameter 40 mm, height 75 mm is cut by plane perpendicular to VP inclined at 55 0 to HP meeting the axis at the top face. Draw the lateral development of the solid. 11. A pentagonal pyramid of base side 25 mm and axis height 60 mm is lying on the ground on its base such that one of the base edges is parallel to and far away from VP. It is cut by cutting planes, one is perpendicular to VP, inclined at an angle of 40 0 to HP and meeting the axis at 14 mm from the base. The other plane is parallel to HP and perpendicular to VP meeting the axis at a distance of 28 mm from the base. Draw the lateral surface development of the cut solid. 12. A cone of 45 mm diameter and 60mm height is cut by a horizontal plane at a distance of 15 mm from the apex and another plane inclined at 30 0 to HP and meet the axis at 15 mm above the base. Draw the development of the cone. 13. A right regular cone of 50 mm base diameter and axis 60 mm long stands on its base on HP. A circular hole of 12 mm radius is drilled through the axis of the cone at a height of 15 mm above the base of the cone. The axis of the hole is perpendicular to VP. Draw the development of the lateral surface of the cone with holes in it. 6/12 Department of Mechanical Engineering, Sri Eshwar College of Engg

94 GE A hexagonal prism of side of base 35 mm and axis height 60 mm stands on its base in HP with two of its rectangular faces parallel to VP. A square hole of side 30 mm is drilled, such that the axis of the hole is perpendicular to VP with all the rectangular faces of the square hole are equally inclined to HP and bisects the axis of the prism. Draw the development of the lateral surface of the prism showing the shape of the hole formed in it. Assignment 4: Sectioned Solids and Development of Surfaces SD1. A pentagonal pyramid of base side 25 mm and altitude 60 mm rests on the HP on one of its base with an edge parallel to the VP at a distance of 8 mm form the axis. Draw the top view, sectional front view and true shape of the section. SD2. A hexagonal prism of base side 25 mm and altitude 55 mm rests on its base on HP with two edges of the base parallel to VP. A cutting plane parallel to the HP cuts the prism at a height of 25 mm above the base. Draw the front view and the sectional top view. SD3. A cone of base diameter 40 mm and altitude 50 mm rests on its base on HP. It is cut by a section plane perpendicular to both HP and VP, 10 mm to the right of the axis. Draw the top view, front view and sectional side view. SD4. A cube of side 30 mm rests on its base on the HP with a vertical face inclined to VP. It is cut by a plane perpendicular to the VP and inclined at 50 0 to HP. The plane bisects the axis of the cube. Draw the development of the surfaces of the right portion of the cut cube. SD5. A pentagonal pyramid of base side 30 mm and height 50 mm rests on its base on HP, with a base edge parallel to VP. It is cut by a plane perpendicular to VP, 50 0 to HP meeting the axis 30 mm above HP. Draw the development of the lateral surfaces. SD6. A cylinder 40mm diameter and 70mm height is resting on its base on V.P. It is cut by plane passing through a point 50mm from the base and inclined at 40 to V.P. A through hole of 20mm diameter is drill at 30mm above the base. Develop the lateral surface of the cylinder. UNIT V - ISOMETRIC AND PERSPECTIVE PROJECTIONS Principles of isometric projection of simple solids and truncated solids, combination of two solid objects. Perspective projection of simple solids - Prisms, pyramids and cylinders by visual ray method. Isometric Projection 1. Draw the isometric view of a frustum of a cone of base diameter 50mm, top diameter 30mm which is resting on its base on HP with its axis perpendicular to HP. 2. A hexagonal prism of base side 20 mm and height 40 mm has a square hole of side 16 mm at the Centre. The axes of the square and hexagon coincide. One of the faces of the square hole is parallel to the face of the hexagon. Draw the isometric projection of the prism with hole to full scale. 3. A hexagonal prism of base side 25mm and axis height 50mm rests on HP on its base with a base edge parallel to VP. It is cut by a plane inclined at 50 to HP and perpendicular to VP and is bisecting the axis. Draw the isometric view of truncated prism. 4. A cylinder of 50 mm diameter and 75 mm height stands with its base on H.P. It is cut by a section plane inclined at 45 to H.P and perpendicular to V.P, passing through a point on the axis 20 mm below the top end. Draw the isometric projection of the truncated cylinder. 5. A pentagonal pyramid of base side 30 mm and axis length 65 mm is resting on HP on its base with a side of base perpendicular to VP. It is cut by a plane inclined at 30 to HP and perpendicular to VP and passing through a point ON the axis at a distance of 30 mm from the apex. Draw the isometric view of the truncated cylinder. Department of Mechanical Engineering, Sri Eshwar College of Engg 7/12

95 GE A cone of base diameter 50mm and axis height 70 mm rests on HP on its base. It is cut by a plane inclined at 30 to HP and perpendicular to VP and bisects the axis. Draw the isometric view of the truncated cone. 7. A square pyramid of base of 25mm side and 50mm long axis rests centrally over a trapezoidal block of top and bottom bases of 40mm and 60mm sides respectively with the thickness 30mm. Draw the isometric projection of the arrangement. Perspective Projection 1. A cube of 30 mm edge is resting on a face on the ground such that one of its faces is parallel to PP and the center of the solid is 50 mm behind the PP. The station point is 40 mm in front of the picture plane, 45 mm above the ground plane and lies in a central plane which is 30 mm to the left of the nearest vertical face of the cube. 2. Draw the perspective projection of a cube of 25 mm edge, lying on a face on the ground plane, with an edge touching the picture plane and all vertical faces equally inclined to the picture plane. The station point is 50 mm in front of the picture plane, 35 mm above the ground plane and lies in a central plane which is 10 mm to the left of the center of the cube. 3. A rectangular prism of base size 25x40x60 mm rests with it s on the ground such that the longer base edge recedes 30 to the right of PP with one end of it behind PP. The station point is 45mm in front of PP, 35 mm above GP and lying on a central plane 35 mm from the nearest vertical edge. Draw the perspective view. 4. Draw the perspective projection of a pentagonal prism of base side 20 mm and height 40 mm when it rests on its base on the GP with one of its rectangular faces parallel to and 20 mm behind the PP. The SP is 45 mm in front of PP and 60mm above GP. The observer is 30 mm to the left of the axis. 5. A regular hexagonal pyramid of base edge 20 mm and height 35 mm rests on its base on the ground plane with one of its base edges touching the picture plane. The station point is 30 mm above the ground plane and 40 mm in front of the PP. The central plane is 30 mm to the right of the axis. Draw the perspective projection of the pyramid. 6. A cylinder of diameter 50 mm and length 60 mm lies on ground with its axis perpendicular to the PP and one of its circular base touching the PP. The SP is 45 mm to the right of the axis of the cylinder, 40 mm in front of the PP and 70mm above GP. Draw the perspective projection of the cylinder. Assignment 5: Isometric and Perspective Projections IP1. A cylinder of 35 mm diameter and 55 mm height stands with its base on H.P. It is cut by a section plane inclined at 55 to H.P and meeting the axis at 15mm from the top end. Draw the isometric projection of the truncated cylinder. IP2. A cone of base diameter 25mm and height 40mm rests centrally over a frustum of a hexagonal pyramid of base side 40mm, top base 30mm and 60mm height. Draw the isometric view of the solid IP3. A cylinder of diameter 50 mm rests on ground vertically with its axis 5 mm behind PP. The observer point is 40mm infront of PP, 100 mm above GP and is 10 mm to the right of the nearest base corner point. a central plane passing through the apex. Draw the perspective projection. IP4. A square prism of 55 mm edge of base and 70 mm height is placed on the ground behind the PP with its axis vertical and one of the edges of the base receding to the left at an angle of 40 to the PP. The nearest vertical edge of the solid is 20 mm behind PP and 25 mm to the left of the observer who is at a distance of 120 mm in front of PP. The height of the observer above the ground is 100 mm. Draw the perspective view of the prism. IP5. A pentagonal pyramid side of base 25 mm a and height 50 mm rests with one of its corner of the base touching the e picture plane and the base edges passing through this corner making equal inclinations with 8/12 Department of Mechanical Engineering, Sri Eshwar College of Engg

96 GE 8152 the picture plane. The station point is on the central line, 100 mm in front of the picture plane and 75 mm above the e ground. Draw the perspective view of the pyramid. UNIT I - PLANE CURVES AND FREE HAND SKETCHING Curves used in engineering practices Conics Construction of ellipse, parabola and hyperbola by eccentricity method Construction of cycloid Construction of involutes of square and circle Scales: Construction of Diagonal and Vernier scales. Free hand sketching of multiple views from pictorial views of objects Engineering Curves: Ellipse, Parabola & Hyperbola 1. Draw the locus of a point P moving so that the ratio of its distance from a fixed point F to its distance from a fixed straight line DD is ¾. Also draw tangent and normal to the curve from any point on it. 2. Construct an ellipse given the distance of the focus from the directrix as 60 mm and eccentricity as 2/3. Also draw tangent and normal to the curve at a point on it 20 mm above the major axis. 3. Construct a parabola given the distance of the focus from the directrix as 50 mm. Also draw tangent and normal to the curve from any point on it. 4. The focus of a conic is 50 mm from the directrix. Draw the locus of a point P moving in such a way that its distance from the directrix is equal to its distance from the focus. Name the curve. Draw a tangent to the curve at a point 60 mm from the directrix. 5. Draw a hyperbola when the distance between the focus and directrix is 40 mm and the eccentricity is 4/3. Draw a tangent and normal at any point on the hyperbola. 6. Draw a hyperbola when the distance between its focus and directrix is 50 mm and eccentricity is 3/2. Also draw the tangent and normal at a point 25 mm from the directrix. Construction of Cycloid 1. A circle of 50 mm diameter rolls along a straight line without slipping. Draw the curve traced by a point P on the circumference for one complete revolution. Draw a tangent and normal on it 40 mm from the base line. 2. Construct a cycloid having a rolling circle diameter as 50 mm for one revolution. Draw a normal and tangent to the curve at a point 35 mm above the directing line. 3. Draw an epicycloids generated by a rolling circle of diameter 40 mm and the diameter of the directing circle is 140 mm. Also draw tangent and normal to the curve from any point on it. 4. Draw a hypocycloid generated by a rolling circle of diameter 50 mm and the diameter of the directing circle is 240 mm. Also draw tangent and normal to the curve from any point on it. Construction of Involutes 1. Draw the involute of a square of side 30 mm. Also draw tangent and normal to the curve from any point on it. 2. A coir is unwound from a drum of 30mm diameter. Draw the locus of the free end of the coir for unwinding through an angle of 360. Draw also a tangent and normal at any point on the curve. 3. An inelastic string of length 100 mm is wound round a circle of 26 mm diameter. Draw the path traced by the end of the string. Department of Mechanical Engineering, Sri Eshwar College of Engg 9/12

97 GE 6152 Scales 1. Construct a diagonal scale of R.F 1:30 to read meters, decimeters and centimeters and long enough to measure up to 3m. Also mark a length of 1.76m on the scale. 2. The distance between Chennai and Madurai is 400 km. It is represented by a distance of 8 cm on a railway map. Find the R.F. and construct a diagonal scale to read kilometers. Show on it the distance of 543 km, 212 km and 408 km. 3. Construct a vernier scale to read meters, decimeters and centimeters and long enough to measure up to 4m. R.F of the scale is 1/20. Mark on your scale a distance of 2.28m. 4. The actual length of 300m of an auditorium is represented by a line of 10 cm on a drawing. Draw a vernier to read up to 400m. Mark it, a length of 343m. 2. Draw the orthographic projections of the following component using free hand. Free Hand Sketching 1. Make free-hand sketches of front, top and right side views of the pictorial view shown in the figure 3. Make free-hand sketches of front, top and right side views of the pictorial view shown in the figure 10/12 Department of Mechanical Engineering, Sri Eshwar College of Engg

98 GE Make free-hand sketches of front, top and right side views of the pictorial view shown in the figure CF4. Draw the involute of a circle of diameter 40 mm and draw the tangent and the normal to the involute at a point 95 mm from the centre of the curve. CF5. Draw a hypocycloid of a circle of 40 mm diameter which rolls inside another circle of 200 mm diameter for one revolution. CF6. Draw an epicycloid if a circle of 40 mm diameter rolls outside another circle of 120 mm diameter for one revolution. CF7. Draw the orthographic projections of the following component using free hand. Assignment6: Plane Curves and Free Hand Sketching CF1. Draw the locus of a point P which moves in n a plane in such a way that the ratio of its distances from a fixed point F and a fixed straight line AB is always 2/3. The distance between the fixed point F and fixed straight line is 50 mm. Also draw a tangent and normal on a point on the locus at a horizontal distance of 55 mm from the fixed straight line. CF2. Draw the locus of a point P moving so that the ratio of its distance from a fixed point F to its distance from a fixed straight line DD is 1. Also draw tangent and normal to the curve from any point on it. CF3. The vertex of a hyperbola is 30 mm from its directrix and the eccentricity is 3/2.Draw the hyperbola and draw the tangent and normal at any point on the curve. Department of Mechanical Engineering, Sri Eshwar College of Engg 11/12

99 Table of Content Sri Eshwar College of Engineering Department of Mechanical Engineering Basic Concepts on Mr.S.Gokul Assistant Professor S.No. Topic Page No. 1 Drawing Vs. Engineering Drawing 2 Standards 2 Drawing Sheets 2 Orientation of Drawing Sheet 3 Drawing Pencils 3 Drawing Scales 3 Line Types 4 Projection Method 4 Quadrant System 5 First Angle Projection Vs Third Angle Projection 5 Lettering Technique 5 2 Conic Sections 6 Engineering Curves 6 3 Points. 7 Lines 7 Planes 8 4 Solids. 9 5 Sectioning of Solid. 9 Development of Surfaces of Solids Isomeric Projection. 10 Perspective Projection 11 Multiple Choice Quiz 11

100 ENGINEERING GRAPHICS Drawing vs. Engineering Drawing Drawing Sheets Drawing: Describing any object/ information diagrammatically Engineering Drawing: A drawing of an object that contains all information like actual shape, accurate size, manufacturing methods, etc., required for its construction without the barrier of a language. Standards Standardization is the process of formulating and applying rules for an orderly approach to a specific activity for the benefit Standard Code BIS standards BIS Code IS 10711:2001 IS 10714:1983 IS 9609:2001 IS 15021:2001 IS 11669:1986 Topics Size and Layout of Drawing sheets Line Types and Uses Lettering Projection Methods Dimensioning A Series Formats (mm) A A A A A A A A Sri Eshwar College of Engineering Page 2 of 12

101 ENGINEERING GRAPHICS Orientation of drawing sheet Drawing Pencils Wooden pencils are graded and designated by numbers and letters H for hardness B for blackness 7B, 6B, 5B, 4B, 3B, 2B, B - in decreasing order of softness and blackness HB to F Medium grade H, 2H, 3H, 4H, 5H, 6H, 7H, 8H, 9H increasing order of hardness. Drawings are done using 2H pencils and finished with H and HB pencils to be practiced in this course. Orientation of A3 drawing sheet Drawing Scales Scale is the ratio of the linear dimension of an element of an object shown in the drawing to the real linear dimension of the same element of the object. Designation of a scale consists of the word SCALE followed by the indication of its ratio, as follow SCALE 1:1 for full size SCALE X:1 for enlargement scales (X > 1) SCALE 1:X for reduction scales (X > 1) Page 3 of 12 Sri Eshwar College of Technology

102 ENGINEERING GRAPHICS Standard reducing scales are, 1:2, 1:5, 1:10, 1:20, 1:50, 1:100 Standard enlarging scales are, 2:1, 5:1, 10:1, 20:1, 50:1, 100:1 Dimension numbers shown in the drawing are correspond to true size of the object and they are independent of the scale used in creating that drawing. Line types PROJECTION METHOD PROJECTION THEORY The projection theory is used to graphically represent 3-D objects on 2-D media (paper, computer screen). The projection theory is based on two variables: 1) Line of sight 2) Plane of projection (image plane or picture plane) Line of sight is an imaginary ray of light between an observer s eye and an object. Plane of projection is an imaginary flat plane which the image is created. Sri Eshwar College of Engineering Page 4 of 12

103 ENGINEERING GRAPHICS First angle Projection vs Third angle Projection Quadrant system in 3D First angle Projection Object placed in First Quadrant is above HP and in front of VP Front view is draw above reference line Top view is arranged below FV Left side view is on the right side of FV and Right view is on the left side of FV Symbol Third angle Projection Object placed in Third Quadrant is below HP and behind of VP Front view is draw below reference line Top view is arranged above FV Left side view is on the left side of FV and Right view is on the right side of FV Symbol Quadrant system in 2D Page 5 of 12 Sri Eshwar College of Technology

104 ENGINEERING GRAPHICS Lettering Technique Engineering curves A curve is defined as a continuous line traced out by a moving point, moving by constantly changing its direction CONIC SECTIONS Ellipse, Parabola and Hyperbola are called conic sections because these curves appear on the surface ff a cone when it is cut by some typical cutting planes. These are the loci of points moving in a plane such that the ratio of it s distances from a fixed point And a fixed line always remains constant. A cycloid is the curve traced by a point on the rim of a circular wheel as the wheel rolls along a straight line. A epicycloid is the curve traced by a point on the circumference of a circular wheel which rolls without sipping, around the outside of a fixed circle A hypocycloid is the curve traced by a point on the circumference of a circular wheel which rolls without sipping, along the inside surface of a base circle. Involute: it is a curve traced by an end of a string or thread, when it s unwounded from a circle or a polygon, the thread being kept tight. The Ratio is called ECCENTRICITY. (E) A) For Ellipse E<1 B) For Parabola E=1 C) For Hyperbola E>1 Sri Eshwar College of Engineering Page 6 of 12

105 ENGINEERING GRAPHICS Points in Space A Point may lie in space, in any one of the four quadrants, formed by the two references planes of projections, namely, H.P and V.P. showing the four quadrants formed by H.P. and V.P. When a point lies in the first quadrants, it will be above H.P. and in front of V.P. When the point lies in the second quadrant, it will be above H.P. and behind V.P. When the point lies in the third quadrant, it will be below H.P. and behind V.P. When the point lies in the fourth quadrant, it will be in front of V.P. and Below H.P Lines: It s the locus of a point which moves along the shortest path joining two given points Positions of a Point Page 7 of 12 Sri Eshwar College of Technology

106 ENGINEERING GRAPHICS Planes: A plane is a two dimensional entity (surface, Area or object) having only length and breadth. Sri Eshwar College of Engineering Page 8 of 12

107 ENGINEERING GRAPHICS Solids: it s defined as an object having three dimensions SECTIONING OF SOLID. A solid object is cut by some imaginary cutting plane to understand internal details of that object. Two cutting actions means section planes are recommended. A) Section Plane perpendicular to Vp and inclined to Hp. Development B) Section Plane perpendicular to Hp and inclined to Vp. Page 9 of 12 Sri Eshwar College of Technology

108 ENGINEERING GRAPHICS ILLUSTRATION SHOWING IMPORTANT TERMS IN SECTIONING DEVELOPMENT OF SURFACES OF SOLIDS Development of surface of a solid is defined as the process of opening out all the surfaces of a three dimensional body on to a flat plane. Isomeric projection: it s a pictorial projection of an object in which the three dimensional view of the object is shown Isomeric projection: times of Isomeric projection scale Sri Eshwar College of Engineering Page 10 of 12