Metal Inert Gas (MIG) welding is a popular form of welding. It uses an arc of electricity to create a short circuit between the gun and the metal, which produces heat.
This heat, alongside a non-reactive (inert) gas, melts the metal. The metal is then allowed to cool, which causes it to solidify and fuse.
While that is the basic outline of MIG welding, there is a lot more to it, which this article will cover as well as teach you how to use a MIG welder.
What Are MIG Welders Used For?
These welders are used for smaller manual welding done inside factories or metal workshops. MIG welding has a less steep learning curve than other types of welding that are practiced and, as a result, is a good starting point for novice welders and is also used by hobbyists for small-time projects.
As it has been stated, MIG welding is used for small structures and is generally fast while producing excellent quality. However, it should be noted that MIG welding cannot be used outside, as it is very susceptible to draughts. Workshops will require windscreens to ensure proper welding.
What Is MIG Welding Used For?
MIG is also heavily used because it works well with lots of different metals. To list a few, MIG is used to weld carbon steel, stainless steel, aluminum, magnesium, copper, nickel, and silicon.
What Benefits Do You Get from MIG Welding?
MIG welding has several advantages, which makes it a terrific choice for your welding needs. In case you were confused about whether or not MIG welding is for you or not, then it might help to look through the several advantages it has.
Speed of Welding
It goes without saying that MIG welding is fast. While it also depends on the complexity of the joint or fusion, in most cases, you will find that MIG takes the least time. This is attributed to the continuously feeding electrode, which ensures a fast and smooth process.
Quality of Welding
Alongside being fast, MIG produces very high-quality welding. This form of welding offers good weld pool visibility alongside great control due to the auto-feed wire.
All these work in tandem to provide a simple, efficient, and high-quality weld when working with the large variety of metals MIG welding is compatible with.
Clean and Efficient
MIG welding uses a shielding gas to protect the arc. What this does is reduce the loss of alloying elements and prevents the formation of slag and other waste products.
Furthermore, this ensures high uptime, and there is very little clean up to do. This makes the process fast and less tedious.
Easy to Learn
Despite all these advantages, MIG welding is quite easy to do and teach. In many workplaces, it is very easy and cheap to provide sufficient basic training to employees that will allow them to perform properly.
It is also very easy for people to pick up and use for their projects. Simply having someone demonstrate it or watching a video tutorial is often enough.
Disadvantages of MIG Welders
MIG welders have numerous advantages, but they are not perfect. In fact, they have some issues that people working with them should be aware of.
Can’t Be Used Outdoors
MIG welding is very susceptible to draughts. If your workshop isn’t well built to reduce the wind, you will find the quality of the weld will heavily suffer,
Draughts will also affect the shielding gas and thus make your welding process much messier. This weakness to flowing wind does limit some applications of MIG welding and puts some pressure on the user to find some proper counters to this obstacle.
It goes without saying that MIG welding can be quite expensive. While the initial cost of a MIG welder is not quite that expensive, it should be noted that a MIG welder comes with lots of parts that need replacing at times.
These parts include shielding gas, electrodes, and muzzle tips whose costs can very well pile up and prove to be a hefty expense.
Can’t Be Used for Thicker Metals
While MIG welding can be used for a variety of metals, most of them are comparatively thin metals. MIG welding does not possess the penetrating power to be able to work with and weld thicker metals. This rules out MIG welding in most heavy-duty work.
How to Set up a MIG Welder?
Here’s the process for setting up a MIG welder.
Before you can begin the welding process, it will help you a lot to make sure some things are properly in place. Make sure to go through the list of precautions below before using your welder.
- Proper Clean up
Make sure the metal you’re working on is free of any paint or rust. MIG welders do not interact well with rust or paint on the metal, and as such, you should take time to scrape the paint and remove the rust. You can use a rust remover to help you.
- Inspect the Power Source
Prepare the power source. Keep it close by and check to see if it is properly working or not. Power source failure midway can be very dangerous, and so you should be very careful.
- Welding Wire
Check the welding wire you’re using. Make sure it is not damaged or susceptible to anything. Check it’s stability before use. When choosing a welding wire, remember that as a general rule of thumb, thicker metals will require thicker wires.
- Use Ground Clamp
Attach the ground clamp to the work surface. Make sure it is properly attached as your welding relies on it.
- Wear Protective Equipment
Make sure you have a welding mask, jacket, fire-resistant safety pants, and gloves. Welding produces harmful fumes that will cause health hazards. You should take measures to protect yourself as best as you can.
To ensure that the MIG welder works properly, there are some parameters that you should be aware of. If you’re using a MIG welder, you’ll need to know about these parameters and how much you need to vary them for different scenarios. Some of the parameters are:
- Select the Appropriate Shielding Gas
With the G in MIG standing for gas, you can probably guess how essential the shielding gas is for the process to work. The most common gases used C25 gas and Argon gas. Steel requires C25, while aluminum requires Argon gas.
- Voltage Setting
MIG welders make use of DC voltage, and the voltage setting, in particular, determines the penetrating power of your welder. Having a high voltage setting will allow you to penetrate thicker metals, but if it is too high, you might mess up your weld.
There’s no hard and fast rule that you can use to determine which metal joint requires what Voltage. Your best bet is to refer to the manual of your particular welder and experiment. Most manuals will give you a table that will provide you with a rough idea.
The rest you will need to test and experiment using scrap metal.
- Wire Feed Setting
Wire feed setting is often a difficult setting to correctly set up, especially for beginners. This setting simply determines the amperage (current setting) for your machine. The unit of measurement is IPM (Inches Per Minute).
Having too high a wire feed setting will cause the welder to burn through the metal, and having too low a setting will create a loose and weak joint. Similar to the voltage setting, there are usually manuals dictating what setting to use for different thicknesses.
However, picking the right wire feed setting is much more difficult as you will need to adjust the voltage in tandem to ensure proper welding. There are more comprehensive tables that can help you.
- Gas Flow Rate Setting
This setting controls the amount of gas released during the process. A higher gas flow rate setting will exert more shielding gas and thus protect the weld area. However, too high a setting might cause contamination in the joint, thus weakening it.
In most cases, people using MIG welding prefer to use a setting of 15 to 25 CFM (Cubic Feet per Minute). You can then experiment for better results.
Installation and Welding
After taking the necessary precautions and learning the proper settings to use, you can slowly begin to assemble the welder.
- Set the metal down properly and use a ground clamp. The clamp is necessary for welding to work.
- Install the wire. To do this, simply remove the nozzle and open the holding cabinet of the machine. You will see a screw. Unscrew it and then insert the wire into the opening. Adjust the wire as necessary.
- Check the gas cylinder and make sure the wire is firmly connected to it and that there are no leaks.
- Check and adjust the settings. These include –
- Voltage Setting (Use the gauge on the welder)
- Wire Feed Setting (Use the gauge on the welder)
- Gas Pressure and Flow Setting (Make use of the adjusting screw beside the cylinder)
- Make sure your welding torch has the appropriate amount of wire. If it is too much, you can cut off some of it.
- Proceed to weld bead the metals. If necessary, practice by performing small beads or circular motions using the welder to get accustomed to the feel of your machine.
- After welding is done, lower the gauges to zero.
- Use the depressing trigger on your welding mig gun to lower the CFH levels.
Learn How To MIG Weld
Things to Keep in Mind
- You can make use of a fume extractor to remove harmful fumes. Investing in one is recommended for MIG welding as you’ll be welding inside a room, and thus, fumes can prove very harmful.
- Make sure your wires are straightened out before you begin welding. Bent wires can cause the gas pressure to build up and accidents to occur. When not in use, neatly coil the wires to avoid tripping on them.