50 PROJECTION OF A CUPBOARD
at is projected or shown upon the plane behind it. We do not attempt to depict anything that is upon the rear surface. If this is required, auxiliary planes are assumed upon which the required view is projected, though we can, of course, dot upon any view details which are hidden from the eye.
Having now explained the theory of orthographic projection, we will consider the examples given in detail.
A Dwarf Cupboard, page 51—The size of this cupboard is to be 3 ft. 4 in. long, 1 ft. 8 in. wide and 3 ft. in height. The ends, top and shelf are to be 1 in. thick, the framed doors in. thick with 3J in. hanging stiles, 4 in. meeting stiles, 3 in. top rails and 4 in. bottom rails. The bottom rail of front is in. x 11 in., the back rail z\ in. X J in., and the match-lined back in. X f in.
We have now all the necessary dimensions, and proceed to lay down the block plan. Fig. 1. In the same relative position 011 your paper as it is shown in the copy, draw in with the T-square and set square, to any convenient scale, a rectangle 3 ft. 4 in. x 1 ft. 8 in., and a similar rectangle, Fig. 2, to represent the end elevation 3 ft. X 1 ft. 8 in. You will note that there is little to distinguish these but their position. You have just seen that plans are drawn upon, or parallel with, the ground; and elevations at right angles or perpendicular to the same. Now on our sheet of paper, the line marked G -L mark? the lower limit of ground line for the elevations, and all drawings made above it are in elevation., and all below it in plan.
We next proceed to lay down the details of the cupboard showing its construction, Fig. 3. Draw the lines a-b and d-c, with the. T -square, projecting them from the block plan as shown by the dotted lines ; these dotted lines are known as " projectors," and though printed in the copy, will be in pencil only, upon your drawing, to be rubbed out later when the inking-in process is over. Mark off along a-h 3 ft. 4 in. to scale, and draw the perpendiculars a d, l-c. You will now have an outline on your paper exactly as Fig. 1. and in future work this is all that will be necessary,
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