A lap weld is sometimes made without scarfing the ends. For instance, pieces of 1″ × ¼″ iron are to be welded by the lap method. They are brought to a welding heat without upsetting; taken to the anvil as previously explained for the scarf weld, lapped about ⁵⁄₁₆-inch, as shown in [Figure 30], and welded. This form of welding is used in a hurry-up job where there is no great amount of strain on the work. It is impossible to make a strong weld this way. Very thin stock, either iron or steel, can be welded to advantage in this manner by hammering on the flat sides. The edges, instead of being hammered, are cut off with a chisel, then ground or filed smooth. In welding very thin stock, a little flux is used. Always weld by separate heats, and do not rivet or split the stock to hold both ends in place. This is not necessary. Try to make the weld with one heat. All good welds are made in one heat.
Fig. 30.
Jump Welding.
Fig. 31. Fig. 32.
For example, a piece like the one shown in [Figure 31], is to be made by welding. The pieces should be prepared as shown in [Figure 32]. The square piece is 1″ by 1″ by 6″, the flat one 1½″ by ½″ by 8″. The square piece is heated directly on one end. If the heat cannot be taken short enough, it may be cooled in water so as to upset it with a lip or projection, as shown. This lip can be worked out afterwards with a fuller, or it may be driven into a heading tool which has the top corners of the hole rounded. This will leave the corners of the lip round as shown. The bar at the end should also be made slightly convex, so that the center part comes in contact with the flat piece first. The flat piece is also upset in the center.
In welding, separate heats are taken. With the square bar, handled with the right hand, the pieces are brought to the anvil by the smith. The square bar is set on top of the flat one, and a helper strikes the top piece with the sledge, driving it down into the bottom one. The edge of the lip is then welded fast with a hand-hammer; or a fuller or set hammer is used, the helper striking with a sledge.
Butt Weld.
