Geometric Constructions and Multiview Drawings

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Geometric Constructions and Multiview Drawings

• Professor Dr. Miguel Alonso Jr.

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Outline

• Drawing Parallel Lines and Curves
• Drawing Points
• Dividing an Object
• Marking an Object at Specified Distances
• Orthographic Multiview Drawings
• Drawing Auxilary Views
• Construction Lines and Rays

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Parallel Lines and Curves

• OFFSET command
• Modify-gtOffset, Offset button, type O
• Options Through, Erase, Layer, Multiple
• POINT command
• Draw-gtPoint, Point button, type PO
• Point Style Format gtPoint Style

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Dividing an Object

• DIVIDE command
• DrawgtPointgtDivide, type DIVIDE
• Does not break an object into multiple parts
• Places points where the breaks would occur
• Block option, will be discussed later
• MEASURE command
• DrawgtPointgtMeasure, type MEASURE
• Divides the object according to a measurement at
  specific distances

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Orthographic Multiview Drawings

• Each field of drafting has its own method to
  present views of a product
• Architecture
• Plan views, exterior views, sections
• Electronics
• symbols
• Civil
• Contour lines
• Mechanical
• Multiview

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• Exercise 7-1, 7-2, 7-3

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• Focus on multiview
• Based on the ASME Y14.3M, multiview and sectional
  view drawings
• Orthographic Projections
• Project object features onto an imaginary
  projection plane
• Projection plane is placed parallel to the object
  and perpendicular to the line of sight
• See fig 7-9

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• Six two dimensional views show all sides of an
  object, fig 7-10
• Imagine a cube enclosing the object, each view is
  made as if you were looking through each side of
  the cube
• Front view is primary and placed in the center
• Other views are placed surrounding the center
  view
• Use only enough views to completely describe the
  object

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• Select the front view
• Show hidden features, fig 7-12
• One view drawings
• Showing symmetry and circle centers

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Auxiliary Views and UCS

• Auxiliary view is needed when a surface on the
  object is at an angle to the line of sight
• Slanted surface is forshortened, fig 7-15 and
  7-16
• UCS-user coordinate system
• UCS toolbar, create new and save

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Construction Lines and Rays

• XLINE and RAY
• XLINE extends in both directions, RAY extends in
  one directions
• XLINE
• HOR, VER, ANG, BISECT, OFFSET
• RAY

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• Drawing problems
• 2
• 4
• 10
• 13