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Ortho.ppt
This document discusses orthographic projection and its types. It explains that orthographic projection involves obtaining views of an object by using parallel projectors that are perpendicular to the plane of projection. The key views obtained are the front, top, and side views. It also discusses the differences between first angle and third angle projection systems, with third angle being the more commonly used ISO standard.
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Ortho.ppt
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- 2. ISSUE’S TO BEDISCUSSED • PROJECTIONS AND ITS TYPES • ORTHOGRAPHIC PROJECTION • 1ST AND 3RD ANGLE PROJECTION
- 3. PROJECTION • Any kindof representation of an object on a paper, screen or similar surface by drawing is called projection of that object. 3
- 4. TYPES OF PROJECTION •Pictorial Projection : Length, breadth and height of an object is shown in one view. • Orthographic Projection : Projection obtained when projectors are parallel to each other but perpendicular to the plane of projection. 4
- 5. • An orthographicprojection consists of the view obtained view when the object is viewed from very far away, so that the resulting rays are all parallel. • The parallel rays that are used for constructing the views are called projectors. Orthographic Projections
- 6. OBSERVER MOVE AROUND Front view Rightside view Top view
- 7. THE GLASS BOXCONCEPT Bottom view Left side view Rear view
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- 9. Defining the Six PrincipalViews or Orthographic Views 9
- 10. Plane of projection •Principal Planes • Vertical Plane • Horizontal Plane • Auxiliary Plane • Profile Plane • Ground Line • Front View or Elevation • Top View or Plan • Side View or Profile View 10
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- 12. 12 Front ViewWhen the observer looks at the object from the front, the view obtained is called the front view (FV) or Elevation. FV is seen on the VP. Top View When the observer looks at the object from above, the view obtained is called top view (TV) or plan. TV is seen on the HP. Side Views When the observer looks at the object from side, i.e., from his left-hand side or right hand side, the view obtained is called side view (SV). SV is seen on the PP. Left-Hand Side View When the observer views the object from his left-hand side, the view obtained is called left-hand side view (LHSV). Right Hand Side View When the observer views the object from his right-hand side, the view obtained is called as right-hand side view (RHSV). Bottom View When the observer looks to the object from below, the view obtained is called bottom view (BV) or bottom plan. Rear View When the observer looks to the object from back, the view obtained is called rear view (RV) or back view or rear elevation. ORTHOGRAPHIC VIEWS
- 13. 13 PROJECTION SYSTEMS 1. Firstangle system 2. Third angle system First Quadrant Third Quadrant - European country - ISO standard - Canada, USA, Japan, Thailand
- 14. 14 ORTHOGRAPHIC PROJECTION 1st angle system3rd angle system
- 15. 15 ORTHOGRAPHIC VIEWS 1st angle system3rd angle system Folding line Folding line Folding line Folding line
- 16. 16 ORTHOGRAPHIC VIEWS 1st angle system3rd angle system Front View Front View Right Side View Right Side View Top View Top View
- 17. The relationship onplane paper of the various views in I angle Top View Front View Left View Right View
- 18. The relationship onplane paper of the various views in III angle Top View Front View Right View Left View
- 19. 19 First angle systemThird angle system PROJECTION SYMBOLS
- 20. 20 20 Difference in firstand third angel projection
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- 23. 23 The second and fourthangel methods are not used in practice because after rotating the horizontal plane by 90° in clockwise direction the front view and top are overlapping. So we can not differentiate the front and top vies. Why we are not using second and fourth angle projections ?
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- 25. WRITING STEPS 1. Selectthe necessary views 2. Layout the views. 3. Project the views. 4. Dimension the views.
- 26. 1. SELECT THENECESSARY VIEWS
- 27. 45 152 152 64 2. LAYOUT THEVIEWS A4 25 Choose an appropriate scale 1:1
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- 29. DIMENSION THE VIEWS NOTES 1.Dimensions in millimeters. 2. …. PART NAME x x x x y y y y z
- 30. TRANSFERING THE DEPTH DIMENSION 1.Direct measurement 0123 27 0 1 2 3 Starting point27
- 31. TRANSFERING THE DEPTH DIMENSION 2.Use miter line 45° Views too close
- 32. No line isformed when curved surface tangent to a plane surface. No line No line TANGENT & INTERSECTION Line is formed when curved surface intersects a plane surface. tangent tangent intersect intersect
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- 34. OBJECT FEATURES Edges arelines that represent the boundary between two faces. Corners Represent the intersection of two or more edges. Edge Corner Edge No edge No corner No corner
- 35. Surfaces are areasthat are bounded by edges or limiting element. Limitingelem ent is a line that represents the last visible part of the curve surface. Surface Surface Surface Limit Limit OBJECT FEATURES
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- 37. HIDDEN LINE PRACTICE Hiddenline should join a visible line, except it extended from the visible line. Correct No ! Join Leave space
- 38. Hidden line shouldintersect to form L and T corners. Correct No ! L T HIDDEN LINE PRACTICE
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- 47. 47 Drawing three viewsin III angle FRONT TOP LEFT
- 48. 48 Drawing three viewsin III angle FRONT TOP LEFT
- 49. 49 Drawing three viewsin III angle ? FRONT TOP LEFT
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