The electrode is the most important tool to be chosen if you want to make a welding. Usually the ideal materials, forms and dimensions are selected according to the type of work which has to be carried out. The cone-shaped electrodes for tacking are the most popular ones, since they are perfect for resistance welding and for most of applications; they have to be connected to the wire having the positive pole which comes out from the welding machine. After that the machine generates an electric field which, thanks to the heat, can melt the metal of the electrode in order to combine the two parts.
Besides the standard electrodes there are the special electrodes, especially designed to connect dissimilar steels.