2 Different views of an object Objects may be drawn in different waysMultiviewPictorialBetter for showing true size and shapeEach view only shows two dimensionsBetter for visualizing the objectAll three dimensions shown on a single view
4 Multiview DrawingA multiview drawing is one that shows two or more two-dimensional views of a three-dimensional object.Multiview drawings provide the shape description of an object. When combined with dimensions, multiview drawings serve as the main form of communication between designers and manufacturers.
5 Multiview DrawingAnother name for orthographic projection is multiview drawingInvolves visualization and implementationAbility to see clearly in the mind’s eye an objectProcess of drawing the object
6 Angles of Projection First-angle projection Used by many European countriesObject is projected onto planes from the first angle or quadrantFront view projected to vertical planeTop view projected to horizontal planeLeft-side view projected to profile plane
7 Angles of Projection Third-angle projection Standard for the United StatesThird quadrant is used for projectionFront view projected to vertical planeTop view projected to horizontal planeRight-side view projected to profile plane
8 Choosing Views Most commonly used views Front ViewTop ViewRight Side ViewMost descriptive view is typically designated as the Front View
9 Choosing ViewsComplex objects require three views to describe its shapeSimple objects can be described with two viewsEx: Soda CanThin objects can be described with only one viewDepth is given in a noteEx: Erasing Shield
10 Placement of ViewsViews should be visually balanced within the working space
11 Steps for Centering a Drawing Draw border and title block using light construction linesDraw diagonal lines from corners of border
13 Steps for Centering a Drawing Add:Length 5.13Space 1.50Width 2.00Horizontal 8.63Height 3.00SpaceWidthVertical 6.50
14 Steps for Centering a Drawing Draw a box the size of all viewsMeasure from the center:Half the widthHalf the height
15 Steps for Centering a Drawing Draw in views using light construction lines
16 Adding Details Add holes and features Transfer horizontal and vertical featuresUse miter line to transfer depth
17 Straight EdgesEdges that are parallel to a plane of projection appear as linesEdges that are inclined to a plane of projection appear as foreshortened lines
18 Curved EdgesCurved edges project as straight lines on the plane to which they are perpendicularCurved edges project as curved lines on the planes to which they are parallel or inclined
19 Normal SurfacesNormal surfaces appear as an edge in two opposite principal views, and appear a surface in all other principal views.
20 Inclined SurfacesInclined surfaces appear as an edge in two opposite principal views, and appear foreshortened (not true size) in all other principal views.
21 Oblique SurfacesOblique surfaces do not appear either as an edge or true size in any principal view.
22 Intersections & Tangencies Where a curved surface is tangent to a plane surface, no line should be shown where they join
23 Intersections & Tangencies Where a plane surface intersects a curved surface, an edge is formed
24 What is Multiview drawing? Drawing more than one orthographic view of an object on the same pageOrtho (straight) + graphic (drawing)An orthographic view is drawn looking straight at one side of the object (at 90° to it)Line of sightProjection planeObject
25 Orthographic Projection Orthographic projection is a technique that is used to create multiview drawings.Orthographic projection is any projection of the features of an object onto an imaginary plane of projection. The projection of the features of the object is made by lines of sight that are perpendicular to the plane of projection.
26 Orthographic Projection The best way to understand orthographic projection is to imagine an object contained inside a glass box.
27 Orthographic Projection There is a total of six glass walls surrounding the object. Each wall represents a projection plane onto which a two- dimensional object view will be created.
28 Projection PlaneA projection plane, also referred to as a plane of projection or picture plane, is an imaginary surface that exists between the viewer and the object.The projection plane is the surface onto which a two-dimensional view of a three-dimensional object is projected and created.
29 Orthographic Projection Start by focusing only on the front projection plane.A person standing in front of the object would see only the five corners identified in black.2314line of sightat 90° angle to projection plane5
30 Orthographic Projection Projection lines are used to project each corner outward until they reach the projection plane.
31 Projection LinesA projection line is an imaginary line that is used to locate or project the corners, edges, and features of a three-dimensional object onto an imaginary two-dimensional surface.
32 Orthographic Projection The visible edges of the object are then identified on the projection plane by connecting the projected corners with object lines.
33 Orthographic Projection The orthographic projection process is then repeated on the other projection planes.
34 A Question…Each of the blocks to the right have the same overall dimensions and colors.What else to they have in common?
35 They all have identical top views! Answer ….They all have identical top views!
36 HIDDEN LINES MUTLIVIEW DRAWINGS We place hidden lines in a drawing to do the following things:Show hidden features2. Clarify the position and shape of features3. Make the “plate” more readable(NOTE: The term “plate” refers to a finished drawing.)
37 Cubes (like these dice) have 6 sides How many views?Cubes (like these dice) have 6 sidesSince each side of the die will have its own view…Frontthen there must be SIX possible orthographic views!
38 Cubes (like these dice) have 6 sides How many views?Cubes (like these dice) have 6 sidesTopSince each side of the die will have its own view…then there must be SIX possible orthographic views!Front
39 Cubes (like these dice) have 6 sides How many views?Cubes (like these dice) have 6 sidesSince each side of the die will have its own view…Right Sidethen there must be SIX possible orthographic views!FrontTop
40 Cubes (like these dice) have 6 sides How many views?Cubes (like these dice) have 6 sidesSince each side of the die will have its own view…then there must be SIX possible orthographic views!FrontBackTopBottomThe Front, Top, and Right Side are the views that are usually drawn.Right SideLeft Side
41 All the views MUST be arranged correctly Where do the views go?All the views MUST be arranged correctlyImagine “unfolding” the cube to get proper view alignment.The back view can be placed in any of these four locations.
42 How does this work on other objects? Place the object in a glass boxThen “unfold” the boxFront view is always centralTop view goes aboveR.Side view goes to the right
43 What about details you can’t see? Hidden lines show details that are not seen in all viewsProject from hidden detail to the other viewsDraw hidden lines (dashed) to show the detail
45 Multiview Drawing REVIEW An orthographic view is drawn looking straight at one side of the object (at 90° to it)There are 6 possible orthographic views:Front, Back, Top, Bottom, Left Side, Right SideThe Front, Top, and R.Side views are usually all that are drawnHidden lines show details you can’t see in all views
46 Centering a Multiview Drawing Review Make a sketch of the views needed for the drawing.The space between the views is 1 ½”What are the measurements needed to center the drawing?What is the overall size of the box for the views?
47 Centering a Multiview Drawing Review 3.501.56.751.756.501.53.5011.50
48 Layout of the 6 ViewsSketch the layout of the 6 views of this object and label the views.TOPREARL. SIDEFRONTR. SIDEBOTTOM