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 three-dimensional objects in two dimensions in technical and engineering drawing.
Multi-view 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 left-side plane.
Multi-view Projection—The Glass Box
• By unfolding the box, six views of the object are possible
Multi-view Projection—The Glass Box
Multi-view Projection—The Glass Box
Multi-view Projection—The Glass Box
Multi-view Projection—The Glass Box
Multi-view Projection—The Glass Box
Multi-view 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
