The flat plate may be left as it is, but if
possible a depression should be made at the point where the shaft is to be
placed. With the two parts heated as usual, the bar is dropped into
position and hammered from above. As soon as the center of the weld has
been made perfect, the joint may be finished with a fuller driven all the
way around the edge of the joint.
When it is required to join a bar to another bar or to the edge of any
piece at right angles the work is called a "T" weld from its shape when
complete (Figure 53). The end of the bar is scarfed as described and the
point of the other bar or piece where the weld is to be made is hammered so
that it tapers to a thin edge like one-half of a circular depression. The
pieces are then laid together and hammered as for a lap weld.
The ends of heavy bar shapes are often joined with a "V," or cleft, weld.
One bar end is shaped so that it is tapering on both sides and comes to a
broad edge like the end of a chisel. The other bar is heated to a forging
temperature and then slit open in a lengthwise direction so that the
V-shaped opening which is formed will just receive the pointed edge of the
first piece. With the work at welding heat, the two parts are driven
together by hammering on the rear ends and the hammering then continues as
with a lap weld, except that the work is turned over to complete both sides
of the joint.
[Illustration: Figure 54.
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