Top 12 Disadvantages of Mig Welding that You Should Know

Mig welding is a widely used arc welding process. Like other processes, it has disadvantages aside from advantages. Know well about its downsides to avoid mistakes with this process and improve weld quality and productivity.

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Top 16 Advantages of Mig Welding that You Should Know

Despite its paybacks, Mig welding has some drawbacks that you should grasp well.

1. Sensitivity to contaminants

Mig welding process can only deal with low-to-moderate levels of surface contaminants like mill scale, rust, oil, dirt and paint. All those have potential to cause such problems as incomplete fusion, porosity, poor bead appearance, and even cracking.

2. Sensitivity to wind 

The shielding gas used for this process can be easily blown away when welding takes place outdoor. Even inside, a fan or a wind draft of 5 mph can be enough to induce porosity in welding.

3. Limited positions

High heat input of a Mig welder and fluidity of welding puddle aren’t suited to overhead or vertical welding. Whilst some welders never think of welding in one of those positions, take this factor into account when deciding whether to buy a Mig welder to ensure it can accomplish all of the tasks planned for it.

4. Lack of fusion 

Owing to the ability to weld at low currents, Mig welding has the potential for incomplete fusion welding defect when operating in short-circuit mode. Ensure you always apply the proper procedure for the thickness of material you’re welding. 

5. Portability problem

Moving the welding equipment mayn’t be that difficult though, you also have to deal with the high pressure cylinders containing the shielding gas. Proper care must be taken.

6. Open arc process 

Like most welding processes, Mig welding is an open arc process. Proper care must be taken to shield the welder and by-standers from harmful UV rays.

7. Fast cooling rates

The welded metal will cool at higher rates because they are not covered with slag when the weld is completed.

8. Shielding gas

It can take time to replace the shielding gas bottles, and they can get in the way whilst welding.

9. Time for metal preparation

Before you weld with a Mig welder, the material has to be free of dirt or rust for a good weld got and safety’s sake.

10. Difficulty getting into tight places

The gun is hard to get into tight places.

11. The equipment is pretty complex

The equipment is rather complex, since this process require a direct current source, a constant source, flow of gas, and continuously moving wire electrode. Also, electrodes are available in various sizes and made from numerous metal types to match the welding application.

12. Learning curve associated with Mig welding

As the actual technique employed is different from conventional welding practices, there is learning curve related to Mig welding, even for veteran welders. For instance, Mig welders need push the welding puddle along the seam and away from them.

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Top 16 Advantages of Mig Welding that You Should Know

Those advantages of Mig welding can reason why this process is most widely used process in many countries.

See also:
Top 12 Disadvantages of Mig Welding that You Should Know

Mig welding advantages and disadvantages are commonly determined by kind of Mig welder as well as the nature of the job. Before discussing the upsides and downsides to this process, it’s important to first clarify which Mig welder to use and where it will be used.

Mig welders comes in 1-Phase, 3-Phase and combination 1 and 3-Phase. 1-Phase Mig welders typically have a 115 or 230 VAC, and are used in farms and ranches, home garages, body shops, general repairs, small maintenance work, art work, light fabrications.

Meanwhile, combination 1 and 3-Phase Mig welders give a bit more flexibility for welding. They can finish well the same things as the 1-Phase Mig welder while they are also employed for light manufacturing and fabrication.

Once you know you will be doing the kind of work requiring a Mig welder, you will be able to assess its advantages and disadvantages. Many welding workers would argue that the upsides far outweigh the downsides.

1. Higher productivity

Many welders enjoy higher productivity as a result of time saved by not having to change constantly rods or chip away slag, and not having to repeatedly brush the weld. They are able to work cleaner and faster.

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2. Low cost equipment

You just need invest less than $600 in a welding machine from such reputable manufacturers as Lincoln Electric or ITW. Adding some dollar for shielding gas and Mig wire, you are welding for $700 or less.

3. Low cost consumables

Out of all the processes, consumables for Mig welding cost the least. Mig wire from a large box store is less than $3 per pound, and from a local industrial distributor is closer to $2 per pound.

4. High deposition rates

Especially when compared to stick welding. With Mig welding process, the deposition rates are around 10 pounds per hour (deposited weld metal).

5. Low hydrogen deposits

Unlike stick electrodes and flux-cored wires, solid doesn’t pick up moisture. That’s why it deposits welds consistently with low diffusible levels of hydrogen.

6. Can weld just about every metals

Just by changing the filler wire and sometimes the shielding gas, you can weld stainless steel, carbon steel, nickel alloys, aluminum.

7. Low levels of spatter

Low spatter can be attained by selecting right mode of metal transfer. Pulse, and spray welding can bring this benefit.

8. Unlimited thickness

Mig welding process can be used to weld light gage material and even unlimited thickness by using multiple passes. There need higher amperage and appropriate joint configuration to weld.

9. Easy to learn

Mig welding is easier to learn than stick welding or Tig welding. It takes just a few hours for welders to learn how to Mig weld, and some instructors claim that they can offer basic training in 20 minutes - with most of the time spent on cleaning the weld.

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10. Clean and efficient

Since Mig welding uses a shielding gas for the arc protection, very few alloying elements are lost as metal transfers across the arc. There isn’t slag to remove, which is common for stick welding. Also, just very little weld spatter is produced. Following a brief clean-up, Mig welders can be back on the job thanks to minimal clean-up required.

11. High electrode efficiencies

Mig process gives efficiencies of 93-97%. That means when buying 100 pounds of Mig wire, you can deposit 93-97 pounds of weld metal. Such processes as stick welding has electrode efficiencies of about 65%. This is because of loss from spatter, slag and not consuming the entire electrode.

12. Input voltages

With electric service, you can weld. Smaller machines can operate on 115 volt input. Those machines are limited to around ¼” weld thickness. Some of newer industrial machines can run anywhere from 208 – 575 input voltage on single or 3-phase circuits. Also, Mig welding machines often can run off of the portable generators.

13. Simple and good welds

Mig welding gives better visibility of weld pool. This process is simple, and auto-feed wire offers better control. With Mig welding, it is not hard to produce a great-looking weld.

14. Versatile

Versatility of Mig welding is undeniable. Mig can weld various metals and alloys, whilst operating in various ways – for example, semi, and fully automatic. Mig welding is helpful for many home welding projects. It’s also used by numerous industries. This technique is used for copper, aluminum, mild steel, stainless steel, magnesium, nickel, and lots of their alloys, and iron and most of its alloys. 

15. Faster welding speed

The continuously fed wire would keep both hands free for Mig welding, which enhances welding speed, weld quality, and overall control.

16. Can be used in thin materials

Mig welding process can be quite easily used on thin materials if properly set. GTAW can be used on thin materials, too, but in such cases as Auto Body, Mig welding wins hands down.

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