75. Square-cornered Angle.—[Fig. 55]. Upsetting, chamfering, and forging a square corner. Material required: 10 inches of 1 × 1⁄2-inch iron.
Upset the center by cooling 31⁄2 inches of each end to confine the operation to the required place. The center should be 7⁄8 inch thick, and all upset metal should be forged to one side; the opposite side and both edges should be straight. Draw both ends tapering from where the upsetting ceases to 3⁄4 × 1⁄4 inch at the ends; chamfer the edges of the drawn ends on the straight, flat side, beginning about 2 inches from the center and continuing to the ends. If the drawing and chamfering are properly done, each end will be 51⁄2 inches from the center.
Fig. 55.—Upsetting for a Square Corner.
Heat and bend the stock at the upset center to a right angle, with the upset metal on the outer side to provide for the square corner. The bending should be done over the horn of the anvil to produce the quarter-round fillet on the inner side, and may be confined to the center by cooling both ends to where the upsetting begins.
As bends of this kind are somewhat difficult to make correctly, it would be a great advantage to provide a form which may be made to fit into the vise; then one end of the angle can be held securely with the form while the opposite end is bent over it. By any simple form it is impossible to make the outside corner perfectly sharp and square with one operation; it is therefore necessary to forge the outside corner sharp and square by delivering blows on both sides, somewhat in the manner shown in [Fig. 56], but good judgment must be used in doing this.
Fig. 56.—Square-cornered Angle.
The chamfering may be marred or entirely removed in forging the corner; if so, rechamfer, and if the ends are of unequal lengths, the longer one should be cut off equal with the other. Then all surfaces should be made straight and smooth with the flatter and the scale removed by occasionally dipping the flatter in water.
76. Fagot Welding.—Welding and forging to dimensions. Material required: convenient pieces of scrap iron and a bar of 5⁄8-inch round stock from 24 to 30 inches long.