The Pros and Cons of 4 Welding Methods

Welding processes are as varied as the pieces they create, and choosing the right one can be vital to a project’s success and cost. That’s why it is important to know the pros and cons of MIG, TIG, Flux Core, and Stick welding, and to consider the environments in which each performs best.  Here are some general guidelines to consider as you put together specs for metal fabrication projects.

Shielded Metal Arc Welding (SMAW) is commonly referred to as “STICK” welding and uses a stinger – the handle that holds the weld rod.

Advantages

1. Lower equipment cost than GTAW, FCAW and GMAW. (No bottle, gas hose, flowmeter, or TiIG rig/Wire feeder needed).
2. Quick Change from one material to another.
3. The process lends itself to welding in confined spaces and various positions with few problems.
4. Deposition rates faster than GTAW Manual
5. Easy to move from one location to another. No Wire Feeder and Bottle.
6. Requires no outside shielding gas and can be used outdoors in light to medium wind.
7. The ability to bend the electrode and the small space the electrode takes allows the process to be used in comparatively tight spaces.

Disadvantages

1. Low deposition rate compared to GMAW/FCAW.
2. Filler metal cost per weld can be greater due to a low deposition efficiency that can vary greatly with stub length.
3. Production factor is typically lower due to rod changes and chipping slag (unless welding on various materials).
4. Needs more hand-eye coordination than GMAW/FCAW.
5. Slag must be removed as compared to GTAW/GMAW

Gas Metal Arc Welding (GMAW) is commonly referred to as “MIG” welding and uses a “MIG gun” with a wire feeder.

Advantages

1. High deposition efficiency when used in certain transfer modes.
2. No slag to chip as compared to SMAW and FCAW
3. The process can be used on thin materials with relative ease, if properly set.
4. Lower hydrogen weld deposit with all electrodes.
5. High production factor since no slag is required to be removed and uses a continuous electrode.
6. With the parameters properly set for the application, most people can weld after a very short amount of practice.
7. One given electrode size can be used on various thicknesses of materials productively, as compared to SMAW and GTAW

Disadvantages

1. Requires a wire feeder, which is difficult to move and can sometimes be a maintenance/repair burden.
2. Needs shielding gas, making welding in windy conditions difficult. Generally is not suitable for windy conditions.
3. Out of position welds are sometimes more difficult.
4. Increased chance of lack of fusion if parameters and welding technique are not controlled.
5. The gun is difficult to get into tight places.

Flux Core Arc Welding (FCAW) is commonly referred to as Flux Core welding. It uses the same MIG gun, but there is flux integrated into the core of the weld wire.

Advantages

1. High deposition rate and deposition efficiency as compared to SMAW in all positions. In comparison to GMAW, there is greater deposition rate when used in positions other than flat.
2. With some variations of the process, welding can be performed in mild windy locations, as compared to GMAW.
3. Low hydrogen weld deposit with most electrodes.
4. High production factor compared to SMAW and GTAW since the process uses a continuous electrode.
5. With the parameters properly set for the application, most people can weld after a very short amount of practice.
6. One given electrode size can be used on various thicknesses of materials productively, as compared to SMAW and GTAW

Disadvantages

1. Requires a wire feeder which is difficult to move and can sometimes be a maintenance/repair burden.
2. Needs shielding gas with some wires, so welding in windy conditions can be difficult.
3. Slag must be removed.
4. Increased chance of lack of fusion if parameters and welding technique are not controlled. It is very easy to carry a very large puddle, which can greatly increase the chances for lack of fusion.
5. The gun is difficult to get into tight places.
6. Some of the self-shielded electrodes have limited deposit thicknesses due to the flux and electrode composition.
7. Not very suitable for precision type work as compared to GTAW

Gas Tungsten Arc Welding (GTAW) is commonly referred to as TIG welding. It uses both hands; one holds the “TIG Torch” and the other holds the weld wire.

Advantages

1. GTAW welding offers more precision and higher quality when compared to other welding techniques.
2. It is a difficult skill to learn for many people because you must hold the welding torch in one hand and the filler material in the other for a successful result.
3. GTAW welding uses a cleaner process and you can operate a GTAW welder in almost any position.
4. GTAW welding allows you to choose the precise amperage for your work.
5. You can weld more types of metals and alloys with GTAW welding processes.
6. GTAW welding processes are useful for welding chromalloy, aluminum, steel, nickel alloys, stainless steel, copper, brass, magnesium, and even gold.
7. There are fewer fumes and less smoke when GTAW welding.
8. You don’t need to purchase multiple shielding gases to work efficiently, as Argon gas is typically used for most GTAW welding applications.
9. The cost of a GTAW welder is comparable to the other methods.

Disadvantages

1. GTAW welding is more expensive than the other processes available.
2. Poor gas coverage can lead to contamination issues.
3. You need to understand the correct polarity for your welds.
4. Overheating can be a significant problem when GTAW welding.
5. GTAW welding requires higher skill sets and is a much slower process comparatively.

This is a brief overview of four general welding process types.  There are hundreds (if not thousands) of variations and specifications that determine the best weld procedures for each application. For most projects, your fabricator will be best suited to decide what methods and processes will be best for fit, function, and cost.  Depending on the project requirements, it may make sense to consult with a welding engineer to determine the best process, and a good fab shop will let you know if and when outside help should be brought in.