Many welders love TIG welding as it enables them to have a cleaner finish. With MIG welding, all DIY enthusiasts can make the most out of their maintenance and fabrication needs. The MIG welding process requires the use of a shielding gas that protects the weld puddle and arc. Some of the gases that are commonly used by welders include argon, Co2, or a combination of the two.
Best choice for non-refillable gas cylinders
When using a gas cylinder that will need to be disposed of after use, you can opt for carbon, argon, or a mixture of the two. In this case, the mixture is usually Argon and Co2. The mixture of Argon and Carbon produces a better and malleable weld with no spatter. But the downside of this combination is that it is usually more expensive as the cylinder doesn’t last long.
When used alone, pure carbon can be fiercer and with more spatter. But it has the advantage of lasting longer reducing the cost per minute of each weld. However, if you are using MIG welding for your car restoration project, it’s advisable to use a combination of Argon and Carbon on the visible parts of the car. For hidden areas such as the sills and floors, you can use carbon. This will ensure that you have a better quality where it’s much needed and cost-effectiveness where you aren’t very concerned about the quality.
Best choice for refillable gas cylinders
Refillable gas cylinders offer you more options when it comes to the choice of gases. The simplest option is the use of pure carbon. However, if you need some better quality of Argon and carbon, you can find a wide range of mixtures for the two gases. For the majority of DIY welding projects, a mixture of argon and carbon can be a good choice.
One of the benefits of using the mixture of Argon and carbon is that you can use it to MIG weld stainless steel. For industrial application, you may need some more exotic gases for stainless steel. However, if you are DIYer, you can go with the combination of carbon and Argon.
When it comes to MIG (Metal Inert Gas) welding, the type of gas you need will depend on the material you’re welding and the type of MIG welding you’re performing. Here are some common gases used for MIG welding:
- Argon: Argon is the most commonly used gas for MIG welding. It is used for welding non-ferrous metals such as aluminum and magnesium. Argon is a great option when welding these materials because it provides excellent penetration and arc stability.
- Carbon Dioxide: Carbon dioxide is often used in combination with argon for MIG welding. It is a popular choice for welding mild steel because it is relatively inexpensive and produces a stable arc. However, it can produce a lot of spatter and may require more cleanup after welding.
- Helium: Helium is sometimes used in MIG welding, particularly when welding thick materials. It provides excellent heat input, which can be helpful when welding thicker metals, but can also be expensive.
- Oxygen: Oxygen is used in small amounts for MIG welding, typically less than 5%. It can help increase arc stability and penetration, particularly when welding stainless steel.
In summary, the type of gas you need for your MIG weld will depend on the material you’re welding and the type of MIG welding you’re performing. Argon is the most commonly used gas and is great for welding non-ferrous metals such as aluminum and magnesium, while carbon dioxide is a popular choice for welding mild steel.

Best gas for MIG welding of mild steel
The more the percentage of Argon in the mixture of the shielding gas, the better the quality of your weld. On the lowest side, you can go with a mixture of 75 to as this will enable you to work quickly and provide a cleaner look for your completed project.
Some users go with a combination of Argon and carbon. This combination can handle most of the MIG welding tasks that can be done by a DIYer. It provides a smoother bead finish. However, there are some downsides to a higher Argon mix. For one, it will more expensive. You don’t want a gas whose cost will be more than what you charge.
Secondly, a higher, concentration of Argon will drop the penetration rate of Shielding gases consisting of pure inert gases such as Argon isn’t the perfect choice for MIG welding as they can leave an ugly and inconsistent weld.
The use of carbon for shielding
If you are concerned about the cost, and the quality of the weld isn’t a big concern for you, we recommend that you use a combination of carbon for MIG welding steel. This is not only a cheaper option as compared to the Argon mix but you can easily find it in various supply stores.
While carbon dioxide isn’t among inert gases such as Argon, it provides ample chemical protection or shielding in MIG welding. When carbon reacts with an arc, the result is a hotter aura as compared to the C25 mix. Therefore, if you need a stronger and bigger bead when connecting metal, this can help create that deeper penetration.
When pure carbon is used, the resulting electrical arc may be unstable. This may result in the crackling of the arc and it may pop more resulting in a spatter. The resulting amount of smoke and fumes is usually moderate. If there is a higher amount of spatter, this may result in more cleaning when the work is finished. You should not use pure carbon when you are welding the thinner metal gauges at the low Amps as the arcs can result in holes in the frame.
In conclusion
It can be hard, finding the right gas for mild steel welding. When completing a welding project, you should evaluate your goals and after that choose the right shielding gas for the role. Some of the factors you need to consider include the cost of gas, the quality of the weld, and the method of preparing the material. You should also consider the thickness of the base material, and the post-weld clean-up that is needed.
The majority of professionals use the best MIG welders to maintain many shielding tank gases at their workplace and will only use them for the project they are working on. This results in the best welding gas for various projects. You can also adjust as you move along.