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140
SHEET METAL DRAFTING

Problem 33
RECTANGULAR FLARING PANS

62. Rectangular Flaring Pans.—Frequently, the contour of the ash pit demands that a furnace or range ash pan be given unequal flares. Such a pan is shown in Figs. 189 and 190. It should be noted that the sides of the pan flare 2 in. as shown in Fig. 189, while the front end flares 5 in., and the back end flares 3 in. as shown in Fig. 190.

The Elevation.—A front and side elevation should be drawn, setting forth the exact dimensions of the pan. The pan is stiffened around the upper edge with a ¼-inch rod. When this rod is covered with the wire edge, not less than ⅜ in. should be allowed for clearance. Thus a pan measuring 34¾ in.×16¾ in. outside of the wire would measure 34 in.×16 in. inside of the wire. The pan has two profiles A,B, C, D of Fig. 190, and E, F, G, H of Fig. 189.

The Pattern.—Two lines of stretchout are drawn at right angles to each other as shown by the dotted lines of Fig. 191. The spacings of the profiles are set off upon these fines of stretchout, the spacings A,B,C, and D being taken from Fig. 190, and the spacings E, F, G, and H being taken from Fig. 189. Measuring lines are drawn at right angles to the line of stretchout through each of these points. The flares 5 in., 3 in., and 2 in. should now be set off at their respective corners as shown in Fig. 191. The inclined lines representing the meeting lines of each corner should be put in.

A ¾-inch lap is added to each corner of the sides of the pan, and a center line for the rivet holes drawn in. The centers for the rivet holes should also be located in the laps. With the corner of the bottom (point P) as a center, arcs intersecting a straight line drawn ⅜ in. in from the meeting line of the end should be drawn. Only one corner of Fig. 191 is treated for rivet holes, but it is required that the rivet holes for all corners be located. The ⅝-inch edge for covering the ¼-inch rod may now be added to complete the pattern.

The Bail—The bail is shown in Figs. 189 and 190 by dotted lines. Since the bail is below the top line of the pan, it must be drawn carefully in order to scale the dimensions accurately. It is generally placed so that the bail ear will be to the rear of the center. The ear is attached in such a manner that the "stop" will