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Basic Constructions

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Revision as of 12:03, 22 February 2015 by DT Online (talk | contribs) (Added images and content)

Although modern drafting aids and Computer Aided Design tools now do much of the work for us, an understanding of some basic Geometrical Construction can be useful when setting out large shapes, lofting or working on site such as on a stage set for example.

Typically, the equipment used in these constructions include: straight-edges and rules, set-squares, compasses, dividers and trammels or beam-compass.

Dividing a Line into Equal Parts
  • Draw a construction line at an angle from the end of the line to be divided.
  • Set dividers to any convenient size and step off the required number of equal divisions along this construction line.
  • Join the last division on the construction line to the end of the line to be divided.
  • Draw lines parallel to it through each of the other points.
  • By Similar Triangles the original line is now divided into equal parts.

DividingLines.png
Drawing Parallel Lines using Set Squares and Straight Edge
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DrawingParallelLines.png
Constructing a 60 deg Angle
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60deg.png
Constructing a 90 deg Angle
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90deg.png
Bisecting and Angle
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BisectAngle.png
Bisecting a Line
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BisectLine.png
Constructing Parallel Lines
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ParallelLine.png
Constructing a Perpendicular to a Line.
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PerpendicularToLine.png
'Constructing a Perpendicular from a Point to a Line
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PerpPointToLine.png

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