Both MIG and TIG welding are procedures that use electrical arcs to create enough heat for melting down metals into liquids. Both methods use filler material to join metal pieces together, and inert gas is also used to prevent welding electrode corrosion for both procedures. Despite these similarities, these welding types remain quite different in their approach, and with different purposes for their use.

Generally speaking, MIG welding is a good low-cost bet for completing jobs on steel and aluminum quickly, whereas TIG welding is typically reserved for more expensive, high-quality, and precise jobs–requiring more training to master and taking a lot longer to complete.

For a better understanding of which welding type to use and when, let’s take a closer look at both of these processes!

What Is MIG Welding?

This type of welding is often called ‘point and shoot’ welding due to its similarities to aiming and pulling the trigger on a gun. Metal inert gas (MIG) welding works by feeding metal wire continuously from a spool connected to an electrode into the weld–with wire being used to join the two metal objects together as a filler material. 

An electric current flows through the filler wire to produce an arc. While it’s touching the metal being welded, the arc is generated. With this short-circuit welding process, you move the gun at a steady speed along the joint upon starting the arc until the job is done.

Pros with welding technician training may know that MIG welding is effective on many thicker types of sheet metal. It’s also a lot easier to pick up as a trade, and a faster process than the more precise art of TIG welding.

What Is TIG Welding?

If you’re interested in attending welding school, you’ll eventually hear about the more finicky art of tungsten inert gas (TIG) welding. Here, the metals you’re looking to weld together need to have a tungsten electrode running a current through them. Once the metals have been liquefied by the heat of the electrode, you join the pieces together by putting filler material into the weld puddle.

Unlike the one-handed use of a MIG welder, TIG welding requires both of your hands for the filler and the torch, since they are separate here. You control the electricity coming to your torch via a foot pedal, which allows for a level of deep penetration and accuracy that prevents the arc weld splatter that can result from a more basic MIG job. 

In order to feed the wire, you must have a steady hand and stay extremely focused while moving through the weld. The level of control made possible by this procedure allows for a much cleaner weld—perfect for high precision, more advanced jobs. With TIG welding, you don’t even necessarily need filler material to get a successful join.

How to Decide Which One to Use After Welding Technician Training

With any weld job, looking at some key components of the work at hand will help you decide whether to use the MIG or TIG approach. Cost is your first consideration, with TIG jobs typically being much more time consuming, and therefore more expensive to complete. To execute fast and low-cost jobs, MIG is best. 

The thickness of the metals you wish to weld is next on the list, with MIG welds generally being much more effective on thicker, bigger pieces of sheet metal than TIG. Finally, you should consider the aesthetics of the job. Welding requiring any filler material is usually a messier procedure. The precise metal-to-metal welds that TIG welding can enable is splatter-free, allowing for the smooth, neater surface you’re looking for.

When talking about MIG and TIG welding, it’s really not possible to say that one type of welding is definitively better than another. Both procedures are necessary in the world of liquefying and joining metals, and both take a good deal of training to master—with MIG being the more basic starter skill that can later lead to performing the more precise art of TIG welding.

Are you interested in pursuing a thriving career by taking professional welding classes? 

Contact North American Trade Schools today for more information on its exciting welding diploma program!