Special coated electrode for welding pure aluminium. Weld metal has good color matching with base metal and high electrical conductivity. Hold the electrode perpendicularly to workpiece, with a short arc length, during welding. If the thickness is greater than 10 mm or in large workpieces, preheating shall be applied between 150°C to 250°C. Since slag residues are corrosive, they must be completely removed from the weld bead. Electrode serves well as consumable in oxyacetylene welding. The covering being hygroscopic, electrodes must be stored in an absolutely dry location, or redried if required.