The electric arc burns between the workpiece and the melting electrode. At the same time, the electrode provides the filler material.
The welding rod is clamped into the electrode holder and the welder guides the rod to the seam location Generally speaking, the electrode core wires is encased.
As the electrode melts, the flux covering disintegrates as well, giving off shielding gases and slag that protect the weld pool and arc from the atmospheric air.
After the weld pool has cooled, the slag must be removed.