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3-3. Striking An Arc
−
Scratch Start Technique
Y
Welding current starts as
soon as electrode touches the
workpiece.
.
The scratch-start technique is
preferred for ac welding.
1
Electrode
2
Workpiece
3
Arc
Drag electrode across workpiece
like striking a match; immediately lift
electrode slightly after touching
work. If arc goes out, electrode was
lifted too high. If electrode sticks to
workpiece, use a quick twist to free it.
S-0049
1
2
3
3-4. Striking An Arc
−
Tapping Technique
S-0049
Y
Welding current starts as
soon as electrode touches the
workpiece.
1
Electrode
2
Workpiece
3
Arc
Bring electrode straight down to
workpiece; then lift slightly to start
arc. If arc goes out, electrode was
lifted too high. If electrode sticks to
workpiece, use a quick twist to free it.
1
3
2
