preferred, the paper may he turned around until b- d lies horizontal, when the usual projectors at 30°, as shown at a, may be used. As the completion of this end is merely a repeat of Fig. 2 no further instructions should be necessary.
We may convert the plane figure into a solid by producing the angles of the square to the required distance in a horizontal direction, and drawing its repeat to form the distant end. For the purpose of projecting the cylinder, only one half of the square need be drawn, as the view of the distant side will be intercepted by the cylinder.
Having drawn the half-square as shown, carry the various measuring points across the sides of the prism as indicated by tin; dotted lines, and project them across the end to discover similar points in the curve to those at the front end. The completion of the figure, will then be easy. Of course, when the desired cylinder is obtained the various construction lines are removed.
More Complex Curves (as Fig. 5, a short length of architrave moulding) can be easily projected by a similar procedure. Enclose the orthographic section. Fig. 4, within a rectangle touching its boundaries, and draw perpendiculars to the sides from the various angles and points in the curves ; number these for ready reference and proceed to place the rectangle into isometric projection, its base and edges forming the root lines as shown in Fig. 5. Then transfer the various points, and number to correspond with the original. Project these across each face with the set square of 30", and mark off their various lengths, which give all the necessary points for completing the view, that should be clear by an inspection of the figures.
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