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Rh 13. The Candy Pan.—As already pointed out in the previous problem, the elevation view of an object may sometimes be used as a profile for laying out the pattern. This is the case with the layout of the tin candy pan considered in this problem. Particular attention should be given to the methods of wiring the top of this pan.

The pan shown in Fig. 26 is known to the sheet metal trade as a rectangular flaring pan. Flaring is another word for tapering. Since the sides flare or taper, the bottom of the pan must be smaller than the top. This pan has an equal flare on all sides. Some pans have an unequal flare; that is, some of the sides taper more than others. This candy pan is to be made of sheet tin, wired with No. 12 wire, the corners to be lapped and soldered.

A full size elevation, as in Fig. 27, showing one corner broken away to reveal the wire, is to be drawn. Care should be taken that the flare is equal on both sides. As stated before, this elevation also serves as a profile and is numbered 1, 2, 3, and 4. It should be noticed, in numbering the profile, that the metal necessary to cover the wire is not included. This is on account of the fact that there is a standard allowance for covering wire. For covering a wire with metal, add an edge to the top of the pattern equal to times the diameter of the wire. This allowance, however, must be increased for metal heavier than No. 23 gage.

The plan view is drawn below the elevation as shown in Fig. 28. The line of stretchout is laid out at right angles to the long side of the plan. The spacing of the profile is laid off on the stretchout and is numbered to correspond. The allowance for covering the wire must be computed according to the rule given above. Number 12 wire has a diameter of approximately in. This allowance for wiring is set off to the right of No. 4 and to the left of No. 1 on the line of stretchout. The measuring lines of the stretchout are then drawn. The extension lines from the plan are carried over to the stretchout view and the pattern of one of the flaring sides constructed as shown in Fig. 29. Since the flare is equal on all sides of the pan the other three sides can be laid out