MMA Welding

What is MMA welding?

Manual Metal Arc welding, often known as Shielded Metal Arc Welding (SMAW), stick welding or just arc welding, is a welding process where a coated consumable electrode (or stick) is used to lay the weld.

An electric current produced by the welding power supply is used to create an arc between the electrode and the metal to be welded. The arc melts the core of the electrode to produce drops of molten metal to create the weld.  The flux coating of the electrode also melts and produces a shielding gas and provides a layer of slag which protects the weld from any contamination in the atmosphere. The slag layer needs to be removed after each weld.

What are the benefits of MMA welding?

  • Cost – MMA welding machines are relatively low cost and the operating costs are also lower than with other welding techniques.
  • Mobility – MMA welding machines are compact and lightweight making them easily portable and ideal for use anywhere.
  • Simplicity – the equipment is relatively easy to operate and the procedure is simpler than some other welding processes.
  • Flexibility & versatility – whilst MMA welding is used primarily for welding steel (including stainless steel) and iron, it can also be used for a wide variety of other metals including aluminium, nickel and copper alloys. It is also the most effective process for welding outdoors as it less likely to be affected by weather conditions than MIG or TIG welding.

What are the disadvantages of MMA welding?

  • Quality – MMA welding often produces quality issues which can affect either the strength or the appearance of the weld or both. The most common problems are weld spatter, porosity, poor fusion, shallow penetration and cracking.