Which electrode polarity should be used when welding thin metals?

When welding thin metals, using Direct Current Electrode Negative (DCEN) is advantageous primarily because it provides better control over the heat input during the welding process. With DCEN, the heat is concentrated at the workpiece, which minimizes the chances of warping or burning through the material, a common concern when working with thinner materials. This polarity allows for a more stable arc and reduced penetration, making it easier to create a clean and precise weld without damaging the base metal.

While other polarities like Direct Current Electrode Positive (DCEP) and Alternating Current (AC) have their uses, they generally produce more heat in the electrode, which isn’t ideal for thin metals. DCEP can lead to deeper penetration and can easily burn through when working with materials that are not very thick. AC is typically used for specific applications, such as welding aluminum, but is not as suited for thin ferrous metal welding as DCEN.

For these reasons, DCEN is preferred when welding thin metals, ensuring better control and quality in the weld joint.