Best MIG Welding Settings for Various Steel Types: A Detailed Breakdown

The MIG welding (inert gas welding) process is a very quick and easy-to-learn approach and is typically used in lots of industries because of its efficiency. It is the best choice for joining two metal pieces together if you are working in a workshop, construction site or any other place. The MIG welding process has many benefits.

It produces strong and clean welds and is a very high-speed weld. It can be used on different types of steel. Right welding settings play a very important role in getting the best results. There are different types of steel and their settings vary according to their type.

Different types of steels have different characteristics like thickness, strength and resistance to heat. Using incorrect settings can cause weak joints and damage to the material. In order to increase the quality of the welding process, you have to get a deep understanding of voltage, ampere, wire speed and shielding gas.

In this guide, we will discuss different types of steel and their various settings in detail. Different types of steel require different adjustments and settings in order to produce clean welds. For example, there are different voltage and gas requirements for stainless steel and mild steel.

Understanding the MIG welding settings:

If you want to get the best results, you should understand different welding settings like voltage, amperage, wire speed and shielding gas. Otherwise, you will get weak and incomplete welds.

Voltage:

During the welding process, the voltage level should be controlled properly. It should not be too high or too low. Too low voltage results in weak joints. The reason for this is the weld will not penetrate enough. If the voltage is too high, it will result in excessive spatter and burn-through. The correct voltage depends upon the thickness of the metal which is being welded. If the steel is thick it will need high voltage and if it is thin it will require low voltage.

Amperage:

The electrical current flow through the welding wire is controlled and determined through amperage. How the metal melts and fuses is determined by amperage. If your steel is thicker, higher amperage is needed and if your steel is thin, then a lower amperage level will work best. By using proper amperage levels, you can prevent burning holes in metal.

Wire feed speed:

The speed of the wire feed speed plays a very important role in the welding process. It controls the speed of the welding wire which is being fed into the arc. Too low speed can lead to poor penetration and on the other hand, too high speed can cause wire to pile up and create an uneven weld. The thickness of the wire determines the correct speed.

Shielding gas:

Different types of steels require different shielding gases. The shield gas protects the steel from contamination. If you are working on mild steel, then a mix of carbon dioxide and argon is the ideal choice. If you are working on stainless steel, then a mix of argon, carbon dioxide or special tri-mix gas is used.

MIG welding settings for stainless steel:

Voltage and amperage:

For the stainless steel which is thin (up to 1.6mm/1/16 inch), you should use 16-18V and 40-70A to prevent burn-through.
For medium-thickness steel (1.6 to 3.2mm/1/16 to ⅛ inch set the voltage level to 18-20V and the amperage between 70-100A.
For thick stainless steel (above 3.2 mm / ⅛ inch), set the voltage level to 20-22V and amperage level to 100-140A.

Wire feed speed:

For thin stainless steel, 0.030-inch wire should be set between 150-350 inches per minute.
For medium thickness, a 0.035-inch wire should be set between 100-280 inches per minute.
For thick metals, a 0.045-inch wire should be set between 70-200 inches per minute.

Shielding gas:

For stainless steel, a mix of 90% helium, 7.5% argon and 2.5% CO2 is best for short-circuit transfer.
For faster spray transfer welding, 98% argon and 2% oxygen are used.
Use push technique for clean weld and ER308L wire.

MIG Welding settings for galvanized steel:

Dealing with galvanized steel is difficult because it has a zinc coating in it. It can create fumes and weaken the welds.
If you are using thin galvanized steel, set the voltage between 16-18V and amperage between 40-70A, for medium thickness use 18-20V and 70-100A. The thick galvanized steel needs deep penetration so use 20-22V and 100-140A.
The fire feed speed is adjusted based on the size of the wire. For example, 0.030-inch wire should be set between 150-350 pm and 0.035-inch wire is best at 120-330ipm.
To reduce spatter and increase penetration 100% CO2 is used or 75% argon with 25% CO2. Before starting the welding, it is better to grind off the zinc coating.

MIG welding setting for mild steel:

For mild steel which is thin, use 16-18V and 40-70A. For mild steel which is medium, you should use 18-20V and 70-100A. If you are dealing with thicker steel, you should apply 20-22V and 100-140A.
The wire feed speed depends upon the wire size. 0.030-inch wire should be set between 150-350 inches per minute. 0.035 inch at 120-330ipm works ideally best.
For deeper penetration use 100% CO2 and in order to produce welds with less spatter use 75% argon and 25% CO2. A push technique is best for gas coverage.

Best MIG welding settings for high-strength steel:

If you are dealing with thin high steel strength, it is recommended to set the voltage between 16-18V and 50-80A. For medium-high steel strength, use 18-22V and 80-120A. For dealing with thicker metals, use 22-26V and 120-180A.
The wire feed speed for a 0.030-inch wire diameter should be set at 150-300 inches per minute. For 0.035 inch wire set it at 120-280 inches per minute.
You should use 75% Argon and 25% CO2.

Conclusion

To sum up, proper techniques should be used and settings should be adjusted according to the stainless steel type. In order to prevent cracking and brittleness, use proper preheating and slow cooling down. By following the safety precautions welders can produce high-quality welds.