What happens if the welding arc length is too short?

When the welding arc length is too short, one of the primary consequences is that the welding wire may burn back. This occurs because the arc, which is a stream of ionized gas that produces heat to melt the metal and the filler material, needs a certain distance to function effectively. If the arc length is reduced excessively, the heat generated can become concentrated at the point where the wire meets the workpiece, leading to overheating.

As a result, the welding wire can literally melt back towards the welding machine instead of smoothly melting into the weld puddle. This burning back can create inconsistent welding quality and may even cause operational issues if not corrected, indicating the importance of maintaining an appropriate arc length for effective MIG welding.