How to Set Up a MIG Welder for Thin Metal? Ultimate Guide

Last updated on August 14th, 2023

When you are MIG welding thin metals, it requires utmost precision and accurate welding parameters, or you will risk potential issues. 

Welding defects like burn-through, distortion, and weaker joints are common when you have not adjusted weld-setting properly. 

So, if you are a beginner in the world of MIG welding or a DIY enthusiast who wants to master the art of MIG welding on thin metals, then this article is tailored to your needs. 

In this post, I will be sharing detailed insights about how you can set up your MIG welder for welding thin metals. 

So, without any further ado, let’s get right to it:

Understanding The Challenges of Welding Thin Metals

Welding thin metals with a MIG welder is no easy task. You will require some skill and practice before you get used to the process. 

It poses several challenges including the risk of burn-through and distortion. Let’s get into a bit more detail so you can understand it in a better manner. 

Basically, heat is mainly responsible for problems in thin metal welding. When the heat input is too high it can lead to a burn-through or distortion.

The heat input can be high because of a number of reasons. You might have set the amperage or voltage too high, or the travel speed of the welding gun is too slow. Hence, the heat input will increase on the metal leading to a potential issue. 

High heat input can also lead to warping, as the metal expands and contracts because of subsequent heat and cooling. It might create a concave shape, which will also mean a weaker weld. 

You might be thinking that just lowering the heat input should solve the problem, but that is not the case either. 

If you reduce the heat input on thin metals without adjusting it properly, it can lead to weaker welds with a ropey appearance. 

This appearance is due to a lack of penetration and excessive spatter. 

So, unless you set up the MIG welder properly and adjust the settings appropriately, you won’t be able to weld thin metals with a MIG welder. 

Step-by-Step Guide to Set Up MIG Welder for Thin Metal

Here is a step-by-step guide that can help you set up your MIG welder properly for thin metal sheets:

Step 1: Selecting the Right Equipment

First of all, you will need to select the right type of MIG welder. For welding thin metal sheets, you will need a MIG welder that comes with lower amperage and voltage settings compatibility. 

If you are running low on budget, then you will have to purchase a MIG welder that is suited specifically for thin metals, but if you have a good budget then you can go with a versatile MIG welder that is portable. 

The versatile machine comes with adjustable settings that will allow you to use it for a wide range of tasks. Make sure it has the ability for lower amperage and voltage settings that range. 

The amperage settings should be as low as 20-50 amps and the voltage should be as low as 10-30 volts. 

If your advanced MIG welder supports these settings, then you can use it for welding thin metals. 

Most of the portable and modern MIG welders come with a wide compatibility range and support these settings. 

Step 2: Checking Wire and Shielding Gas Compatibility

The second step is to select the right type of shielding gas and welding wire. Again, the choice will depend on the specific type of metal you are welding. 

You will have to use a wire that is of the same nature as the base metal and the shielding gas will be according to the base metal as well. 

Also, you will have to specifically choose the welding wire that comes with an appropriate diameter for the required thickness of the base metal. 

For thin metal sheets, the ideal wire diameter is 0.024 – 0.036 inches. You can use these wires as they don’t require much amperage or voltage to melt off and hence are ideal for welding thin metals. 

You can refer to the weld process specifications (WPS) when available for more details. There are various guides and online tools that will help you find the right compatibility features. 

Related: What Gas Does a MIG Welder Use? Role of Gas in MIG Welding

Step 3: Selecting the Contact Tips and Drive Rolls

You will also need to use specific contact tips and drive rolls depending on the type of wire you are using and the thickness or diameter of the wire. 

The instructions are often inside the MIG welder for the drive rolls. You can use the user manual and guide readers to find out the details pertaining to the specific welding requirements depending on the base metal and thickness. 

Step 4: Prepping the MIG Welder

In this step, you will have to go through the initial setup process. Now you have all the required equipment in one place. Appropriately connect this equipment. 

You will have to connect the welding gun, ground clamp, and gas supply to the MIG welder. 

Make sure that you have chosen the right type of gas, wire, and wire diameter. 

Step 5: Adjusting the Welding Parameters

Once you have adjusted all the equipment in place, the next step is to adjust the welding parameters. 

This is the most important step that will be decisive whether you get a good weld quality or weld defects. 

As I have already explained, you need to adjust the welding parameters including voltage, amperage, and wire feed speed properly to ensure that you don’t get burn-through or distortion. 

Amperage and voltage play a crucial role in welding thin materials using both 0.024-inch and 0.30-inch solid wires. 

For the best results, a welding current of 30 to 50 amps is recommended. When using the 0.024-inch wire, it is advised to operate within a voltage range of 13 to 15 volts with electrode-positive polarity.

On the other hand, the 0.30-inch solid wire requires a slightly higher voltage, ranging from 15 to 17 volts. These variations in voltage ensure effective fusion and penetration for different wire sizes, providing sturdy and clean welds.

Related: How to Weld Sheet Metal (Thin) with MIG Welder? Ultimate Guide

Step 6: Stabilizing the Base Metal

When working with thin metal sheets, you have to pay a lot of attention to the stability of the base metal. 

Since the metal sheet is already very thin, even a minor push during the welding process can cause burn-through, distortion, or warping and ruin the piece of base metal. 

Hence, you need to ensure that you secure the base metal in a tight fit before you begin the welding process. 

You can do this in several ways. You can either use a workbench to hold the base metal in place or use ground clamps to secure it in one place. It will ensure that the base metal is secure and doesn’t move during the welding process.

Step 7: Safety Equipment

Never compromise your safety. Before you begin the welding process, you must ensure that you are wearing safety equipment. 

The safety tools for welding include welding gloves, helmets, fire-resistant apparel, and welding shoes. 

You must ensure that you are wearing appropriate gear to protect yourself from the potential dangers of the welding process. 

Step 8: Running a Test

Now you are all set up for starting the MIG welding process for thin metal. Do a test run on a piece of scrap metal to see if you have adjusted the welding parameters correctly. 

If everything goes well, then you can move on to the welding process. 

However, if you face any problems with scrap metal, then you can fine-tune the settings until you achieve the desired results. Since it is a piece of scrap metal, you won’t have to worry about experimentation and can adjust the settings comfortably. 

Once you have gotten the right settings, you can begin the welding process. 

Step 9: Welding Technique

Once you have set up the MIG welder properly, the only challenge that remains to avoid welding defects on a piece of thin metal is your welding technique. 

Your welding gun travel speed and angle also play a crucial role in the strength, quality, and appearance of the resultant weld. 

When it comes to travel speeds, precision is essential. For both wire sizes, maintaining a steady pace is crucial for successful welding. 

The travel speeds for 0.024-inch and 0.30-inch solid wires should be kept between 10 to 20 inches per minute (ipm). 

For the 0.024-inch wire, a wire feed speed of 130 to 160 ipm is recommended, while the 0.30-inch wire operates optimally at 75 to 100 ipm. 

By adhering to these specific ipm ranges, welders can achieve single-pass flat and horizontal filet welds of superior quality, ensuring a secure and professional end result.

So, you must ensure that you are using the appropriate technique for the welding process. 

If you are unable to avoid overheating and burn-through issues, then opt for stitch welding or tack welding techniques to create quality and durable welds. 

Related: Which is the Best Gas For MIG Welding? Explained With Images

Frequently Asked Questions

Is MIG welding good for welding thin metal?

Yes, MIG welding is very effective when it comes to welding thin metals. You can use MIG welding for quickly welding thin metal sheets. MIG welding yields high production and welding speed when welding thinner materials. 

Can I weld thin metal with any MIG welder?

No, you must select a MIG welder that comes with low amperage range compatibility. If your MIG welder doesn’t have lower amperage or voltage compatibility, then you won’t be able to use it for welding thin metals. 

What is the best method for welding thin metal in MIG welding?

Short-circuit transfer method is the best method for welding thin metals in MIG welding. This method operates at lower welding parameters as compared to other methods which makes it ideal for this task. 

Is it better to MIG weld or TIG weld thin metal?

TIG welding is ideal for thin metals as it has the utmost precision and accuracy. Nothing can match it when it comes to thin metal sheets. However, TIG welding is slower and more expensive, which makes MIG welding a more suitable choice for many welders. 

Is MIG welding thin metal good enough?

Yes, MIG welding is a versatile process that can be used for welding thin metals too. MIG welding has high productivity and is easier to learn. So, beginners can learn to use this method quite easily and use it for welding thin materials. 

Wrapping Up!

To sum it all up, setting up the MIG welder for thin metal welding application is a crucial process and requires utmost attention and precision. 

Failing to set up the MIG welder properly will lead to potential weld defects. It may sound like MIG welding thin metals is a difficult task at first, but once you get hold of the technicalities you will be able to do it much more efficiently and quickly. 

The above guide provides you with detailed insights into the art of mastering MIG welding for thin metals. 

If you still have some questions, drop them in the comments section below and I will get back to you as soon as I can.