Engineering Drawing  Geometric Construction, Orthographic and Isometric Projection

Upload
carryprameswari 
Category
Education

view
1.247 
download
13
description
Transcript of Engineering Drawing  Geometric Construction, Orthographic and Isometric Projection
121 1208Engineering Drawing I
Carry Prameswari
Program Studi Teknik PenerbanganFakultas Teknologi Kedirgantaraan
Universitas Dirgantara Marsekal Suryadarma
Topics
• Geometric Construction• Orthographic Projection• Isometric Projection
Geometric Construction
Geometric Construction
• Construction of primitive geometric forms (points, lines and planes etc.) that serve as the building blocks for more complicated geometric shapes.
Geometric Constructiona. Point :
 Non dimensional geometrical element.  Occurred by interception of various lines.
Geometric Constructionb. Line : One dimension geometrical element occurred by moving of a point in various direction.
Geometric Constructionc. Plane:  Occurred by at least
three points or connection of one point and one line.
 A plane is always 2D When the number of
element forming a plane increases, shape and name will change.
Geometric Construction
Relationship of One Line to Another Line or Arc
Bisecting a Line
Dividing a Line into Equal Parts
Orthographic Projection
Orthographic Projection• Reference:
Technical Graphics
• Advantage—Represent features of an object more accurately
• Example problem
Orthographic Projection
• Orthographic projections are a collection of 2D drawings that work together to give an accurate overall representation of an object.
Orthographic Projection
Projection Drawing
• Isometric projection is a method for visually representing threedimensional objects in two dimensions in technical and engineering drawing.
Multiview Projection—The Glass Box• Placing parallel planes to the
principal planes forms a glass box (always observed from outside the box)
• To show views of a 3D object on 2D piece of paper, it is necessary to unfold the planes such that they lie in the same plane
• All planes except the rear plane are hinged to the frontal plane, which is hinge to the leftside plane.
Multiview Projection—The Glass Box
• By unfolding the box, six views of the object are possible
Multiview Projection—The Glass Box
Multiview Projection—The Glass Box
Multiview Projection—The Glass Box
Multiview Projection—The Glass Box
Multiview Projection—The Glass Box
Multiview Projection—The Glass Box
Which Views to Present?
Which Views to Present?
• General guidelines– Pick a Front View that contain the most
information that describe the object– Normally the longest dimension is chosen as the
width (or depth)– Most common combination of views are:• Front, top and side view
– Any other view that is different from the principal views is called an Auxiliary View
Minimum Drawing View
• 3 view• 2 view
Projection Angle
Projection Angle
Projection Symbol
First Angle European
Third Angle American
Projection Angle
Exercises
Exercises
Exercises
Exercises
Exercises
Exercises
QUESTION ???
Thank You