When arc welding light gauge metal in the vertical position, in which direction should the welding be carried out?

When arc welding light gauge metal in the vertical position, the welding should be carried out from the top down. This technique ensures better control of the molten weld pool, as gravity helps to keep the molten metal in place and minimizes the risk of sagging or burning through the thinner material. Additionally, welding from the top down allows for better penetration into the base material, leading to a stronger bond in vertical applications.

Choosing this method also helps in reducing the occurrence of defects like undercutting and allows for a smoother finish, as the welder can better manage the heat input and maintain a consistent travel speed. This is particularly important in light gauge materials, where excessive heat can easily compromise the integrity of the weld and the base material.