How to Set-Up a MIG Welder


Joining two pieces of metal together requires a specialized welding technique. While there are several types of welding procedures, the process that is mostly exercised by both industries and daily fabrication is MIG welding.

If you want to bless your DIY projects by adding a professional touch it's time for you to start MIG welding. So, maybe you have already bought a MIG welder or intend to buy one. But you don't know how to set-up a MIG welder? No worries, setting up a MIG welder is not complicated at all. You can easily plug the thing in, crank up the gas shield and start welding. So, without any further ado, let's dive into the topics.

How Does a MIG Welder Work?

Knowing how does a MIG welder work give basic knowledge about its all technical terms. So, it's important to know if you want to learn how to set it up perfectly. The MIG is a welding process that joins metals together by creating heats between a wire electrode and the workpiece. The wire electrode is fed through a MIG gun and it is a consumable process that molten weld pool. To protect the arc from any deterioration a shielding gas is released through the MIG gun. It also secures the weld pool from being contaminated by the air.

How to Set-Up a MIG Welder

To get your desired outcome from welding, having the correct settings is extremely significant. You need to set the machine based on the type of metal you want to weld. There are no fixed settings for every metal type. The density of the metal also plays a huge impact on the settings.

There are 3 main settings that you have to look up before welding. They are Voltage Setting, Wire Feed Speed Setting and Gas Flow Rate Setting.

I discuss them all with additional information about how to pick the right gas and MIG wire. Let's read out this easy set up process of MIG welder.

1. Voltage Settings

While MIG welding, it's important to have the MIG welder on the right polarity. DC is the most common type of voltage that is used for controlling the machine. In MIG welder D/C electrode (+) positive are used commonly. The direct current flows into the handle of the welder from metal by making its circuit. The settings generally come with decent customization. If you need to change it, you must adjust the level of the regulator to control voltages. To do that, unbolt the internal leads and change the polarity settings in the top right corner of the device.

The main heat setting of the welder comes from voltage. It affects the joints, metal thickness, gas type and position of the weld. The settings of voltage depend on what size electrode is operated, how thick the workpieces is and what type of gas is used. Since MIG welders use CV or Constant Voltage power sources, the voltage does not vary very much while welding.

2. Wire Feed Speed

The wire feed speed means how fast the wire is fed by the weld joint. They are regulated in IPM or Inches Per Minute. It also attends for regulating the amperages. Unlike Stick and TIG welding, the voltage doesn't get modification depending on the arc size in MIG welder. In MIG welder, the amperage changes based on wire feed speed and electrode stick-out, although the voltage settings stay similar. A rapid wire fed between two metals creates better attachments. This means you are getting more amperage through the wire and the high heat.

Low speed makes works slow and creates an unstable arc. On the other hand, a high-speed welder burns too fast that it can scorch through the metal and provides a finishing with lots of spatter. So, it is important to choose the speed of wire wisely.

Use the chart below to set the wire speed based on the wire size. For example,

By multiplying the wire size with inches per amperage, you can select an ideal wire speed. For example, when the wire size is 0.23 inches, multiply it by 3.5 inches per amp, which directs to 3.5 x 125 = 437.5 ipm. For .030-inch wire, multiply it by 2 inches per amp. For .035-inch wire multiply by 1.6 inches per amp and for .045 inch multiply it by 1 inch per amp.

As selecting the right settings for wire-speed is a little bit complex, you can take the help of this calculation. It is made based on estimated voltage with amperage relying on the thickness of the material and wire size.

Picking the Right MIG Wire

If you are preparing a thicker metal to weld, you should go for thicker wire. In most welding packages, you'll find a manual where a wire speed and voltage chart provided. The chart prescribes the right kind of wire size for various metal lengths. If you don’t get a manual, you can follow this guide for selecting wire sizes.

  • 0.23″ wire performs great for small welding machines. It is used to weld thin sheet metals from 24-16 gauge
  • 0.3″ wire is the wire size that normally arrives with the MIG welder as it is the best size to weld metals around 1/8 inches thickness.
  • 0.35″ wire is a sufficient size to weld metals around 1/4 inches thickness. It's a favorite choice for novices.
  • 0.45″ wire is excellent size to weld metals around 1/4 inches thickness. This size is ideal for industrial welding.

3. Gas Flow Rate Setting

Shielding gas is used to protect the welding area from any air that can pollute the weld. Set the gas flow rate in CFM or Cubic Feet Per Minute. Remember that, the lower gas flow is not enough to safeguard the weld area and it can lead to porosity in the surface of the weld.

However, too high settings if gas flow is also not good at all. It can cause turbulence and can smell in more air. So, to ensure a perfect gas flow set the MIG settings properly and do some trial.

Right Kind of Gas

The gas is the major element in the setup of a MIG welder. But before that, you have to choose the right gas for your welder.

There are two most common types of gas that is used for MIG welder, Carbon Dioxide and a mixture of Carbon Dioxide and Argon. If you want to weld carbon steel, you will require ER70s electrode with C25 gas, whereas, for welding Aluminum, you will need ER4043 with 100% Argon gas.

Prepare the Joint

Paint or oil on the surface produces a poor and unstable arc. So, clean the surface of the metal that you want to weld nicely if you want a perfect welding finishing. Know that a dirty joint can even lead to a burning area. For welding carbon steel, prepare it by polishing it and for stainless steel, wipe it with any solution. To get an excellent welding finishing, clean welding rods with acetone.

Installing MIG Wire

When you are done with the above settings you need to install the MIG wire onto the welding device. Follow these steps below to install the MIG wire.

  • Slip out the nozzle and contact tip from the bottom of the device.
  • Unlock the cover of the machine and open it.
  • Unfasten the cap from the spine and insert the wire spool inside it.
  • Unhook the pressure and release on the feeder. By twisting the pressure roll, adjust the tightness.
  • Now insert the MIG wire and keep it inside straightly.
  • Wrap up the spool of wire and press trigger to start injecting the wire.
  • Lock the contact tip and the nozzle back on to the device.

Final Words

Unlike other welding processes, learning MIG welding is easy and doesn’t require a coordinated procedure. You can gain proficiency in less than a few weeks. All you have to do is, learning how to hold the gun along the proper position over the workpieces. But before that, you must have to know how to set-up a MIG welder. So, give this writing a thorough read for getting a great set up for your welding assignment.

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