Removing surface defects, grooving cracks for welding, chamfering out of faulty welds, surface cleaning of cast iron of poor weldability.
Strike the arc , and hold the electrode at a very low angle: 10 degrees to 20 degrees, depending on the depth of the groove required. Push the electrode forward, maintaining contact with the metal. The force of the arc will blow the metal away, quickly and neatly, leaving an ideal surface for subsequent operations. Any slag residues remaining in the groove are easily removed by chipping and brushing. To pierce holes, first establish the arc and melt a small puddle. Then place the electrode vertically into the puddle, and push the electrode through with gentle pressure. To enlarge the hole, move the electrode in the required direction.