Which welding method is less likely to cause buckling or warping of thin metal sheets?

Electric Arc (TIG) Welding is considered the best method among the given options for minimizing buckling or warping of thin metal sheets. This is primarily due to its ability to generate a controlled heat source that can be finely adjusted. TIG welding produces less heat input compared to other welding methods, which translates into a lower risk of thermal distortion in the material.

The heat-affected zone (HAZ) is smaller with TIG welding, making it easier to manage the temperature rise and cool down periods, leading to reduced stresses in the surrounding metal. This characteristic is crucial when working with thin sheets that are particularly susceptible to buckling and warping from excessive heat.

In contrast, methods like gas welding and gas-acetylene welding typically introduce much higher amounts of localized heat, which can lead to significant warping as the metal cools. Electric resistance welding may be suitable for joining sheets but typically involves more substantial material thickness or different types of joints that do not lend themselves well to precision work with thin materials. Thus, the controlled approach of TIG welding makes it the preferred choice for joining thin metal sheets while keeping warping and buckling at bay.