Problem 18
TANGENT TEE NOT AT RIGHT ANGLES
35. The Tangent Tee Not at Right Angles.—Figure 111 shows a side elevation which has the same appearance as the side elevation of Fig. 106. The branch pipe, however, is tipped towards the eye as will be seen by studying Fig. 112. Every tangent tee at other than right angles must have the entire miter line developed. The method of drawing this problem does not vary from that of the preceding one. Consequently, the method need not be repeated here. The student is cautioned to follow each step carefully.
The student has perhaps noticed a similarity of method for developing the patterns for all cylinders. Such pattern problems come under the head of "Parallel Line Drawing," which takes its name from the fact that the sets of extension and construction lines are parallel to one another. The following general rules apply to parallel line developments, and, if carefully followed, can be applied to any problem of this class with success.
Rule 1.—Draw a side elevation, if necessary, to show a true miter line.
Rule 2.—Draw a front elevation, if necessary, to show a true miter line.
Rule 3.—Draw necessary profiles.
Rule 4.—Divide the profiles into equal spaces, and number the divisions.
Rule 5.—Carry extension lines from each division of the profile to the miter line.
Rule 6.—Develop a miter line if necessary.
Rule 7.—Draw a line of stretchout, transfer the spacing of the profile to this line, and number to correspond.
Rule 8.—Draw the measuring lines of the stretchout.
Rule 9.—Carry the extension lines over into the stretchout, from each division of the true miter line.
Rule 10.—Trace the intersections of the stretchout, beginning at the profile, thence to the miter line, and from there to a correspondingly numbered line in the stretchout.
Front elevations. Figs. 107 and 112, could be dispensed with in tee joints at right angles. As a matter of fact, experienced layer-
