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The A.C. supply current cable at the back of the welder is provided with three separate wires. One of these is red in colour, and being the ground wire should be connected to a water pipe or other suitable ground. The grey and the black wires are for connection to a 220-volt single-phase line, or to any two of the three wires of a 220-volt three-phase line, or to the two outside wires of a three-wire 110-220 lighting circuit line. Replacement of metal topsThe body construction of older Studebaker cars differs from that of most other makes along the seams where the top is joined to the rear quarter panel and where the roof rail is attached to the top over the door openings. A four-sided frame is used, and the spot welding has to be done by inserting the tongs through openings in the four-sided frame. It is because of this that the specially constructed tongs No. 5 and No. 6 are required. The windshield frame is attached to the top the same as on other cars using tongs No. 2 and No. 3
Picture left illustrates the method used for spot welding the rear window frame to the top using the same tongs. Pictures middle and right illustrate the box frame construction, and show the tongs to use in spot welding the top to the roof rail over the door openings (tongs Nos. 2 and 6) and also the rear quarter panel to the top (tongs Nos. 3 and 5). The operation is the same on Willys bodies. To operate as an arc welderThe stencil on the front of the welder contains complete information as to the size rod to use for all thicknesses of metal, and what plug to use for each heat range. The permanently attached cable (under stencil on front of welder) is the ground lead, and must be securely grounded to the metal to be welded. Then, to obtain from 15 to 25 amperes, plug the detachable cable into No. 1 socket (under stencil) and rotate the control switch. There are six positions on the switch, which provide six heats for each plug-in socket. With the cable in socket No. 2, the heat obtained ranges from 30 to 45 amperes in progessive steps between these heats, as the control is rotated. Note.-When using 15 to 25 amperes, it is sometimes difficult to start the arc if the metal is cold, in which case it should be started at a higher rate. Then when the metal and rod are heated, discontinue the arc and turn the control to the lower heat range desired, and proceed in the usual manner. Learning how to arc weldBefore beginning to weld, the metal should be free of oil, rust, scale, etc. Scale and rust can be removed with a scratch brush. The first step.—The first step is in learning to strike and maintain the arc, which is done in a manner similar to striking a match. The tip of the rod is brought into contact with the metal by a short sweeping motion, which, as soon as the arc is struck, carries the rod away from the metal about 1/16 of an inch. Before any attempt to weld is made, the operator should practice striking and holding the arc until it becomes largely an automatic procedure. If difficulty is experienced in striking the arc with the heat selected, it may be necessary to raise the heat as explained in the above Note, and weld for a distance of approximately 1/4 of an inch. Then the heat can be lowered so that it does not burn holes in the metal. It will be noted that the heat is less when the rod is close to the metal, and greater when the heat is farther away, which is just the opposite in acetylene welding. The second step.—The second step is to maintain the arc by keeping a constant gap between the metal to be welded, and the welding rod. This is accomplished by moving the hand slowly in a downward motion at the same speed that the rod burns away, and at the same time the rod should be moved slowly with a uniform motion along the direction the weld is being made. The rate of travel will be governed by the rate of deposit of the welding rod on the metal being welded, and it is advisable to practice depositing the welding rod in a straight line on a single piece of metal. No attempt should be made to join two pieces of metal until the above has been mastered. The third step.—The third step is to attempt to butt weld by placing two pieces of metal together, end to end. The rod should then be moved in a zigzag manner along the seam to be welded. This produces a path for the welding rod, much as are the teeth on a saw. The purpose of this is to secure sufficient penetration of the rod material to the metals on either side of the weld to obtain maximum strength, and to prevent burning of the metal. The fourth step.—The fourth step after becoming proficient in the foregoing is to place two pieces of metal in a vertical position, and, with the amperage of the machine reduced, proceed exactly as is explained in the preceding paragraph, always starting from the top of the seam in order to secure the smoothest weld. The fifth step.—The fifth step is to place two pieces of metal in a horizontal position, and weld them from the underneath side. Having mastered all of these steps the operator is now ready to weld sheet metal. To do this, secure an automobile fender, or similar material, and with the welder set on one of the lower heat stages, proceed in the same manner as explained in the foregoing. Care must be exercised in holding a constant and very close arc, as otherwise the metal being welded will burn through. Also, greater care must be used to strike the arc than when welding thicker metals ; as with the small amperage, this operation is more difficult. As in the case of learning to weld heavy metal, no attempt should be made to weld a seam or tear on the sheet metal until the operator has mastered the ability to weld a neat bead in a straight line. In the event that burning is experienced on an exceptionally thin and rusty piece of sheet metal, a fourth motion of the hand and welding rod is necessary, namely, a rapid up and down motion, much the same as is obtained with an air hammer. Always remember to hold a very close arc, after it has been well established, as the closer the arc, the less the heat.
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