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Mig Spot Welding
Mig spot welding, although sometimes
considered a tacking tool, has gained wide acceptance as a method
of joining which is competitive with
riveting and resistance spot welding. In some applications, it has
replaced continuous welding methods
as it provides reduced welding costs, reproducibility, and adequate
strength for the service requirements
and requires minimum operator skill. Mild steel, stainless steel and
aluminum are very commonly welded with
this method. PROCESS
DESCRIPTION Mig
spot welding, a variation of the continuous mig welding process, fuses two pieces
of sheet material by penetrating
entirely through one of the pieces into the other. There is no joint preparation
required, other than
cleaning, only that the two pieces overlap. However, pieces over 1/4 in. (6.4mm)
generally require a hole
in the top plate and are known as plug welds. Figure 11-1 shows a typical example
of a mig spot weld. Figure
11-1 - Typical Spot Weld - Mild Steel
