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Figure 8-17.—GTA welding a tee joint.
Figure 8-18.—GTA welding a lap joint.
filler rod and bring the arc back to the front edge of the
puddle. When the puddle becomes bright and fluid
again, you should repeat the steps as described before.
Figure 8-16 shows the correct procedures for adding
filler metal. Continue this sequence until the weld joint
has been completed. The width and height of the weld
bead is determined by the speed of travel, by the move-
ment of the torch, and by the amount of filler metal
added.
In welding practice, it is again stressed that good
(GTA welding depends on following this definite proce-
dure—form the molten pool and then feed filler rod
intermittently to the leading edge of the pool as you
move the torch forward. DO NOT feed the filler rod into
the arc. You should practice making single-pass butt
welds until you can produce satisfactory welds.
LAP AND TEE JOINTS.— In chapter 3, we said
that lap and tee joints are welded using the fillet weld.
Fillet welds are slightly awkward to make using the GTA
welding process because of the gas nozzle. Once you
establish the arc, you should pay close attention to the
molten puddle. Figures 8-17 and 8-18 show the correct
torch and rod angles for the tee and lap joints.
In welding a tee or lap joint, the puddle forms a
V-shape. The center of the V is called a notch, and the
speed at which you fill the notch governs how fast you
should move the torch. Do NOT get ahead of the notch.
If you do, the joint will have insufficient fusion and
penetration. As you weld along the joint, dip the rod in
8-11
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