Getting started
There are many welding processes to choose from — but no single welding process is suitable for all applications. It is critical to consider your welding skills, the basic processes available, and the capabilities and advantages of each to determine which process is best for your needs and applications.
Overview of welding processes
The most common processes are MIG, TIG and stick. Each has benefits and limitations for certain applications. There’s no one-size-fits-all approach.
- MIG/Gas Metal Arc Welding (GMAW) — MIG welders use a wire welding electrode on a spool fed automatically at a constant pre-selected speed. The arc, created by an electrical current between the base metal and the wire, melts the wire and joins it with the base, producing a high-strength weld with great appearance and little need for cleaning. MIG welding is clean and easy and can be used on thin or thick metals.
Similar to MIG, flux-cored arc welding (FCAW)* is a wire-feed process but differs in that self-shielded FCAW does not require shielding gas. Instead, flux-cored wire shields the arc from contamination. This is a simple and efficient approach, especially when welding outdoors, in windy conditions or on dirty materials. FCAW is widely used in construction because of its high welding speed and portability.
MIG and flux-cored welding are easy to learn and can create extremely clean welds on steel, aluminum and stainless. Both processes have the capability to weld materials as thin as 26 gauge.
*The FCAW process is offered through Miller® MIG machines.
- TIG/Gas Tungsten Arc Welding (GTAW) — This arc welding process uses a non-consumable tungsten electrode to produce the weld. The weld area is protected from atmospheric contamination by shielding gas (usually argon) and filler metal, though some welds, known as autogenous welds, do not require it. A constant-current welding power supply produces energy that is conducted across the arc through a column of highly ionized gas and metal vapors known as plasma.
TIG welding is most commonly used to weld thin sections of alloy steel, stainless steel and nonferrous metals such as aluminum, magnesium and copper alloys. The process grants the operator greater control over the weld, allowing for strong, high-quality welds. TIG is comparatively more complex and difficult to master than other processes and is significantly slower.
- Stick/Shielded Metal Arc Welding (SMAW) — Stick for many years has been the most popular method for most home-shop welding. This process uses an electric current flowing from a gap between the metal and the arc-welding electrode. Stick is effective for welding most alloys or joints and can be used indoors and outdoors or in drafty areas. It’s also the most economical method and provides the ability to create a good bond on rusty or dirty metals.
However, it is limited to metals no thinner than 18 gauge, requires frequent rod changing, emits significant spatter and requires that finished welds be cleaned. Stick welding is also more difficult to learn and use, particularly the ability to strike and maintain an arc. Arc welders are available in AC, DC or AC/DC, with AC being the most economical. It’s used for welding thicker metals of 1/16 inch or greater. These machines are a good choice for farmers, hobbyists and home maintenance chores.
The diagram below summarizes each welding process. Consider these factors when deciding which process might be best for your general needs.
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MIG Welding
- Easiest process to learn
- High welding speeds possible
- Better control on thinner metals
- Cleans welds possible with no slag to clean
- Same equipment can be used for flux-cored welding
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TIG Welding
- Provides highest quality, precise welds
- Highly aesthetic weld beads
- Allows adjustment of heat input while welding by use of a foot control
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Flux-Cored Welding
- Works as well as stick on dirty or rusty material
- Out-of-position welding
- Deep penetration for welding thick sections
- Increased metal deposition rate
- More forgiving when welding on dirty or rusty material
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Stick Welding
- Better suited for windy, outdoor conditions
- More forgiving when welding on dirty or rusty metal
- Works well on thicker materials
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What process best fits your needs?
Identify the types of welding projects and materials you will weld most of the time. Are you creating metal sculptures? Do you intend to restore an old muscle car in your garage? Does the motorcycle you bought years ago require some fabrication? Maybe you need to do basic repair on farm equipment.
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Possible Projects
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Average Material Thickness
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Auto body
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3/16 inch or less
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Trailer frames and fencing
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1/4 inch to 5/16 inch
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Farm, ranch and landscape
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5/16 inch to 3/8 inch
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Thick structural components
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Over 3/8 inch
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Bicycles, lawnmowers or tube frames
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1/16 inch
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Boats, cars and motorcycles
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1/16 inch to 1/8 inch
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Hunting stands and utility trailers
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1/16 inch to 1/8 inch
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General to heavy repair
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3/16 inch to 1/4 inch
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Taking the time upfront to identify the projects that will occupy the biggest percentage of your welding activity will help you determine the specific metal thickness you will likely weld most often — and ultimately help you select the most suitable welder.
Time to get a bit more specific. Let’s take a look at what welding process you can use for each metal type. Keep in mind that many of these materials are also processed using varying combinations of two or more metals to reinforce strength and functionality.
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Metal
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Weld Process
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MIG
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Stick
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TIG
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Steel
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X
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X
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X
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Stainless Steel
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X
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X
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X
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Aluminum Alloys
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X
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X
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Cast Iron
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X
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Chromoly
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X
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Copper
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X
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Brass
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X
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Exotic Metals (Magnesium, Titanium, etc.)
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X
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What factors should you consider when determining a budget?
The type of welder you purchase should be suited for the specific functions you require as well as the projects you will work on the most. Think about your end goal and consider opportunities to expand the usefulness of your welder. Will you want more power or amperage in the future? Will you ever want to learn or use additional welding processes?
It is important to take note of the varying amperage and power requirements as well as the duty cycle necessary to achieve the most effective and economical operational results for the projects you’re looking to complete.
In addition to the cost of the welder itself, don’t forget to include costs for the accessories and supplies you’ll need to operate your new welder. This includes welding protection (helmet, gloves, jacket, etc.) as well as gas and consumables.
Don’t feel rushed into making a purchasing decision. Take some time to define your needs. If you have questions or something is unclear, Miller can answer any questions you have about welding processes, benefits, limitations and machine operation. When you’re ready to match a specific model with the task, hobby or business — Miller can suggest the model or product that is the best for you.
Miller has provided quality welders since 1929. When you’re ready to buy, we’d be honored if your first welder was a Miller welder.