MIG Welding FAQs
When you are first delving into the world of welding, a metal inert gas (MIG) welder is a great place to start. These machines are the most popular choice among automotive hobbyists and professional technicians. Read our MIG Frequently Asked Questions for more about why to choose MIG welding for your car.
What is a MIG welder used for?
MIG welders, which join metals using a melted wire electrode, are a relatively simple and fast way to fabricate metal. The MIG welding process is useful for sheet metal, steel structures, home improvement, high-production manufacturing and pressure vessels. It’s also the best way to join dissimilar metals (i.e., attaching steel to stainless steel).
What’s the difference between MIG and TIG welding?
While both processes use an electric arc to create a weld, the arc works in different ways. MIG welding uses a feed wire that moves constantly through the gun while TIG welders use a tungsten electrode to directly fuse metals together (although a filler rod can be added for extra strength). Because of this, MIG welding is easier to learn and more versatile, but TIG welding produces higher-quality welds.
What gas is used in MIG welding?
The standard MIG shielding gas is argon, an inert gas that protects the weld area from contamination. Some fabricators add helium to the mixture, which increases penetration of the weld. A small amount of oxygen or carbon dioxide helps stabilize the arc, which improves overall quality. Adding a little bit of hydrogen is also beneficial when welding stainless steel.
Can you MIG weld aluminum?
You can, but it’s a little tricky. For starters, you will need a special spool gun, such as the one included with the Eastwood 180 MIG welder. It takes more heat to weld aluminum than mild steel — typically 21 to 24 volts. Using a wire welder can also result in unexpected burn-through if you don’t travel fast enough. Because of this, the thinnest aluminum we recommend welding with MIG is 14-gauge.
Can you MIG weld thin metals?
Generally speaking, yes. Most of our MIG welders can weld mild and stainless steel as thin as 24-gauge (and 14-gauge for aluminum, as mentioned above), which covers most automotive projects. Combining MIG with pulsing, in which you heat a small segment at a time, can help reduce burn-through. For steels that are thinner than 24-gauge, we recommend TIG welding because of the additional control you have over input.
Is MIG welding easy?
MIG is generally considered to be the easiest of the major welding methods. DIYers can get the hang of it quickly while still producing good welds. Although you don’t have quite as much top-end potential as you do with TIG welding, the short learning curve and faster production make up for it. MIG welding is also similar to flux core welding and you can do either with the same machine, such as the Eastwood MIG 135.
What are some common MIG welding mistakes?
Here are a few of the mistakes to avoid when learning how to MIG weld:
- Not cleaning and preparing metals enough
- Setting the voltage, wire speed and gas flow too high or too low
- Holding the gun angle too steep
- Setting liner length improperly
- Overheating your consumables from bad wire stick-out or by running the welder too long
- Establishing apoor ground connection
- Using the wrong gun