This section will briefly describe four electrodes that are commonly used for maintenance and repair welding of mild steel. There are many other electrodes available for the welding of other kinds of metals. Check with your local welding supply dealer for the electrode that should be used for the metal you want to weld.
E6010 This electrode is used for all position welding using DCRP. It produces a deep penetrating weld and works well on dirty, rusted, or painted metals

E6011 This electrode has the same characteristics of the E6010, but can be used with AC and DC currents.

E6013 This electrode can be used with AC and DC currents. It produces a medium penetrating weld with a superior weld bead appearance.

E7018 This electrode is known as a low hydrogen electrode and can be used with AC or DC. The coating on the electrode has a low moisture content that reduces the introduction of hydrogen into the weld. The electrode can produce welds of X-ray quality with medium penetration. (Note, this electrode must be kept dry. If it gets wet, it must be dried in a rod oven before use. )
It is hoped that this basic information will help the new or home shop welder identify the various types of electrodes and select the correct one for their welding projects.