True Shapes

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True Shapes The Cone
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True Shape

• This type of drawing is asked to be drawn as part
  of a cut, prism, pyramid, cylinder or cone.
• It shows the actual shape of a sloping surface.
• They can be quite confusing but are not as hard
  to produce as they look.

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True Shape

• As there are other slides and presentations
  depicting how to draw cut prisms, pyramids,
  cylinders and cones we are not going to show you
  how to do these things in this slideshow.
• Instead we will focus on producing the true shape.

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True Shape
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We will assume that the drawing is as shown.
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True Shape
From the Elevation project at 90º the end points
which the cut surface intersects with the
generator lines.
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Draw a datum line for the true shape parallel to
the cut surface.
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Project the other points that intersect the cut
surface.
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True Shape
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Number the lines.
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On the Plan, draw vertical lines from the
intersection between the generator lines and the
curve to the centre line of the circle.
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True Shape
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Using a compass take the distances and put them
on either side of the datum line of the true
shape.
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Connect up the points to show the true shape of
the cut surface.
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True Shape - Cones
The final result.