Page:Sheet Metal Drafting.djvu/146

132 point 1 of the plan, the extension line is traced to the miter line, and thence to a correspondingly numbered line in the stretchout. In like manner, all points of intersection can be located in the stretchout. A curved line passing through these points will give the miter cut. The pattern is completed by an extension line drawn from the

top of the pipe. A lock is added to each side of the pattern. A flange (not shown) should be added to the miter cut.

The Apron.—The exact spacing of points 10, 11, 12, 1, 2, and 2½, as shown on the center line of Fig. 183 by lines a, b, c, d, and e, are set off upon any straight line, Fig. 185. These points also