To lay out the paper for the plates of this work, place a sheet, A B G F, Fig. 38, on the drawing board 2 or 3 inches from the left-hand edge, called the working edge. If placed near the left-hand edge, the T-square and triangles can be used with greater firmness and the horizontal lines drawn with greater accuracy. In fastening the paper on the board, always true it up with the T-square according to the long edge of the sheet and use at least 4 thumb tacks - one at each corner. If the paper has a tendency to curl, 6 or 8 tacks may be used placing them as shown in Fig. 38; many draftsmen prefer one-ounce tacks as they offer less obstruction to the T-square and triangles.
Fig. 38. Standard Lay-Out for Plates.
To find the center of the sheet place the T-square so that its upper edge coincides with the diagonal corners A and G and with the corners F and B, and draw short pencil lines intersecting at C Now with the T-square draw through the point C the dot and dash line D E, and with the T-square and one of the triangles - shown dotted in Fig. 38 - draw the dot and dash line H C K. It will probably be necessary to draw CK first and then by means of the T-square or triangle, produce (extend) CK to H. In this work always move the pencil from left to right or from the bottom upward; except in certain cases.
After the center lines are drawn measure off 5 inches above and below the point C on the line H C K. These points L and M may be indicated by a light pencil mark or by a slight puncture by means of one of the points of the dividers. Now place the T-square against the left-hand edge of the board and draw horizontal pencil lines through L and M.
Measure off 7 inches to the left and right of C on the center line D C E and draw pencil lines through these points N and P, perpendicular to DE. These lines form a rectangle 10 inches by 14 inches, in which all the exercises and figures are to be drawn. The lettering of the student's name and address, date, and plate number are to be placed outside of this rectangle in the 1/2-inch margin. In all cases lay out the plates in this manner and keep the center lines D E and K H as a basis for the various figures. Ink in the border line with a heavy line when the drawing is finished.
In laying out the first few plates of this course the work is to be done in pencil and then inked in; later the subject of tracing the pencil drawings on tracing cloth and the process of making blue prints from these tracings will be taken up. Every beginner should practice with his instruments until he understands them thoroughly and can use them with accuracy and skill. To aid the beginner in this work, the first three plates of this course are practice plates; they do not involve any problems and none of the work is difficult. The student is strongly advised to draw these plates two or three times before making the one to be sent to us for correction. Diligent practice is necessary at first; especially on Plate I as it involves an exercise in lettering.