What disadvantage is associated with the delay in arc reignition during AC polarity welding?

The disadvantage associated with the delay in arc reignition during AC polarity welding primarily concerns the stability of the arc. When there is a delay in reigniting the arc, it can lead to fluctuations in the arc's characteristics, such as voltage and current. This instability can result in erratic arc behavior, making it challenging to maintain an even heat distribution across the weld area. An unstable arc may cause difficulties in controlling the weld puddle and can lead to inconsistent welding results, affecting the overall quality of the weld.

In AC welding, the alternation of current is intended to facilitate certain processes like cleaning the oxide layer on aluminum, but if the arc does not reignite quickly enough, it interrupts this process and exacerbates the issue of instability. The relationship between arc stability and weld quality is crucial, as a stable arc contributes significantly to achieving consistent penetration and bead appearance.