Last updated on June 21st, 2023
Metal Inert Gas (MIG) welding is a popular and versatile welding method that is considered the easiest to learn.
It provides you with strong and durable welds that require minimum cleaning afterward while ensuring a budget-friendly welding process.
You might have heard that MIG welding is pretty straightforward, but you will still need some instructions to get started.
That’s what I am here for. In this article, I will be sharing some of the basics about MIG welding and teach you how you can use a MIG welder effectively.
So, let’s dive into the details of MIG welding and how it works.
The MIG Welder—Important Components
There are different types of MIG welders you can get in the market. However, they all share four key components.
1. The Welding Machine
The welding machine or power source is the device that contains all of the controls and main components of a MIG welder. It takes the input power from a power supply and converts it into the required voltage for the welding process.
Inside the welding machine, there is a wire spool that contains the welding wire which will be fed into the weld pool. The welding torch or gun is attached to the welding machine.
On the external body of the machine, you will find all the controls that are used to make amperage and other adjustments.
2. Gas Supply and Regulator
This process uses gas to protect the weld pool from atmospheric contamination and also to enhance the weld.
In MIG welding, gas is supplied through a bottle or a cylinder which is attached to the welding machine directly.
There are also gasless MIG welders that do not require gas from a cylinder or bottle but rather have wire coated in a special material that turns into gas on contact.
3. Welding Torch or Gun
The welding torch is attached to the welding machine and contains the gas hose as well. It will be used to create the electric arc which is required for the welding process. This is the most important component that you will be working with.
4. Ground Clamp
The ground clamp is attached to the base metal to complete the circuit. You can attach it either directly to the workpiece or to the metal workbench you are working on. As soon as you create a complete circuit, you can touch it to anything you want.
5. Welding Wire or Spool
The spool goes into the set of rollers that are held on with a tension nut. The nut ensures that the spool doesn’t unravel on its own. This spool contains the welding wire that will be used in the welding process.
The nature of the wire depends on the type of material you are going to be welding. For example, if you are welding aluminum, then the aluminum wire will be loaded into the spool.
Any welding process can be harmful because it generates a lot of heat, and you must protect yourself against it. Here are some of the safety precautions you must keep in mind while working with a MIG welder:
- You must wear a welding helmet with auto-darkening shades or a mask. The light generated from welding is extremely bright which can be harmful for both your eyes and skin. Using a mask that is specially made for welding will protect your face and eyes in the best way possible while also making the process visible to the eyes.
- It is better to use leather or welding gloves during the welding process. Unlike TIG welding, you don’t need the thinnest gloves for MIG welding. You can wear any gloves you want as long as they ensure protection.
- Make sure you are wearing fire-resistant apparel when working with a welding machine. Do not wear polyester clothing because it will quickly catch fire or melt and burn you.
- You should wear leather shoes that are fully covering your feet. Do not weld with open-toed footwear because molten metal can fall on your toes. The leather shoes will also protect you from electrocution.
- Always make sure to weld in a well-ventilated area. Do not weld in an enclosed space. Also, make sure that the area is clean and free from any flammable material.
- Always keep a fire extinguisher by your side. In case anything happens, you can always put out the fire to save your precious equipment and more importantly yourself.
- Do not weld galvanized steel ever. It contains zinc coating which can produce carcinogenic and poisonous gas when burned. It will result in heavy metal poisoning that can cause permanent and fatal damage.
- Take breaks during welding as well as the grinding process and drink plenty of water to keep yourself properly hydrated.
Preparing for the Welding Process
Before you begin the welding process, you have to make sure that the following things are in order.
The welding apparatus is properly set up for MIG welding. This means checking that the shielding gas is properly set and the regulator is adjusted as well as the welding parameters are also properly set.
You must also ensure that the length of the welding wire is set at the appropriate length and ground clamp is attached to the base metal.
As for the base metal itself, you must clean it properly to ensure that there is no dust, paint, debris, or anything on it that can contaminate the weld.
Take some time to clean the metal surface properly and grind the edges you are going to weld.
Start the Welding Process and Lay a Bead
Now that the workpiece is ready, and the welding machine has been set up, wear the protective equipment and start the process.
You can start by practicing on a piece of scrap metal. This can be termed as fine-tuning your skills or testing stage where you get accustomed to the welding process.
You don’t need to weld the scrap pieces together. Just ensure that the arc is being generated and everything is working properly.
Once you scratch the electrode or welding wire on the surface, it will create a spark that will start the welding process.
Remember, you don’t keep the welding wire touched to the metal surface for this welding method. It should be about 1/8 inch away from the metal surface.
While scratching is the recommended choice for beginners, some users also prefer to tap the metal surface to initiate the arc. It is more of a personal choice if you ask me.
Once the arc is generated, start laying beads. Pushing or pulling will be decided depending on what type of metal you are working on. You can go with either method for steel but for aluminum, pushing is preferred.
Pulling is easier and faster but it creates more spatter which requires more cleaning afterward. Since aluminum is more susceptible to contamination, pushing is preferred because it looks much neater and requires less cleaning.
Maintain an angle of 15-20 degrees and create the welding beads as smoothly as possible. Remember if you are going too fast, you might not be able to create proper beads, but if you are going too slow, it will create holes through the metal.
So, in the beginning, it might take a bit of practice, but you will learn quickly about the pace and will be able to create perfect welds with MIG welding.
Grinding and Cleaning the Weld
Once the weld has cooled down, you can grind and clean it up using a grinder. The grinding will be required if the portion being welded is going to be visible or if you care about how it is going to look.
One thing you must keep in mind is not to manually cool the weld by dipping it in water or by throwing water on it. It can cause distortion or fissures.
Once the weld has cooled itself you can use a grinder to clean the weld. The amount of grinding required will depend on how neat a weld you have created.
The neater weld you got while laying the bead, the less grinding you will have to do.
Hence, you must work properly in the first place or there is going to be a whole lot of cleaning to do later on.
Remember, if the spatter is very little or if much cleaning is not required, then using a welding brush might do the task. Using a grinder requires careful use or you might just cut through the weld, and you would never want that.
Grinding is a hectic process and might take a bit of time but trust me it is completely worth it. Once you are finished, the two metals will be joined as they were originally one and it will look perfectly clean.
Troubleshooting Common Problems in MIG Welding
You can run into all sorts of problems while welding. Luckily, for every problem, there is a solution.
- If you are experiencing little balls of metal from the splattering that are showing different colors like brown and green, it means there is not enough shielding gas, and you should increase the gas flow rate.
- If the weld is burning right through the material, it means the voltage is too high, so you should lower it. Similarly, if the weld is not penetrating, then the voltage is too low, and you should turn it up.
- If your weld pool is creating large globes after you move through, it means that too much wire is being fed to it. Slow down your wire speed and it should solve the issue.
- If the welding gun is spitting and not maintaining a constant weld, it might be because you are holding it too far from the weld. Remember it should be only 1/8 inch away from the base metal.
- If the welding wire gets stuck on the metal surface, then you should switch to the scratching method instead of using the tapping method for arc initiation.
- If you face any other issues, never hesitate to seek help from a professional.
Maintenance Tips for MIG Welding
You must follow proper instructions for the care and maintenance of your MIG welder. Here are some of the things you must keep in mind.
- Always keep your equipment clean and properly stored. Also, keep the welding area clean as well. Remember, hygiene is most important when it comes to ensuring the long service life of your welding machine.
- Regularly check the gas hose and fittings for any signs of leak or damage. If found, repair or replace them immediately.
- Similarly, check if all the electrical connections are completely secured. If you find any damage on the cables, even a minor one, repair it immediately before it gets worse.
- Always ensure that all of the shielding gas is flushed out of the machine before turning it off and storing it.
- Dispose of any extra welding wire that is left after the welding process is complete. Do not insert it back in.
Frequently Asked Questions
Is MIG welding easy to learn?
Yes, MIG welding is much easier as compared to other welding processes. There is not much of a learning curve, and it is pretty much a straightforward process. So, after a bit of practice, you will be able to do it efficiently.
What is the angle for MIG welding?
The angle for MIG welding is typically around between 10 and 20 degrees while some prefer between 10-15 degrees. However, a professional welder may choose to use his own style of welding with different angles.
What are the 3 tips for MIG welding?
Well, there are no 3 universal tips. If I had to ensure 3 things, they would be to ensure that you have properly prepared the base metal, maintained a consistent travel speed, and always wore safety equipment no matter what.
Do you need gas for MIG welding?
Yes, gas is required for MIG welding. The shielding gas in MIG welding not protects the weld pool from atmospheric contamination but also enhances the overall quality of the weld and assists in the welding process.
What voltage is MIG welding?
There is no one voltage. The exact voltage will depend on the nature of the material being welded and the complexity of the project. Even with those specifics, you might need to change the voltage based on specific conditions.
Do you push or pull when MIG Welding?
Generally, the push is recommended for MIG welding because it creates less spatter and ensures that you don’t have to do much cleaning afterward. Pulling is easier and quicker but creates a lot more spatter.
To sum it all up, MIG welding is pretty easy to learn and with just a bit of practice you will be able to get quite good at it.
The above guide helps you get started with the welding process and learn about the basics. Yes, it is not the definitive guide but gives you instructions about the basics of the MIG welding process.
I hope the guide was helpful to you in learning about the process of MIG welding and how you can use it. If you have any questions, you can drop them in the comments section below and I will get back to you as soon as I can. Happy Welding!
- How to Set Up a MIG Welder for Thin Metal? Ultimate Guide - July 29, 2023
- What Is Burnback On A MIG Welder? - July 6, 2023
- How to Use the Lincoln Electric Power MIG 140 MP Welder? - July 2, 2023