Fig. 310   The Pattern of a Round Pipe to Fit Against, a Roof of ' One Inclination.

Fig. 310 - The Pattern of a Round Pipe to Fit Against, a Roof of ' One Inclination.

In Fig. 310, let A B be the pitch of the roof and C F D E the profile of the pipe which is to miter against it. Let G O P H be the elevation of the pipe as required. Draw the profile in line with the elevation, as shown by C F D E, and divide it into any convenient number of equal parts. Lay off a stretchout in the usual manner, at right angles to and opposite the end of the pipe, as shown by I K, and draw the measuring fines. Place the T-square parallel to the sides of the pipe, and, bringing it successively against the divisions of the profile, cut the pitch line, as shown by A B. Reverse the T-square, placing it at right angles to the pipe, and, bringing it successively against the points in A B, cut the corresponding measuring lines. A line traced through the points thus obtained, as shown by L M N, will finish the pattern.