MIG Welding

Gasless MIG welding vs Gas MIG welding – 6 things you need to know

3 Dec , 2015  

There’s no one size fits all when it comes to welding. So it pays to know the difference between the key types of welding and which is best for your application. Here, we delve into the pros and cons of gas and gasless MIG welding.

MIG welding is not only one of the simplest forms of welding, it delivers great results when done right. There are two types: gas shielded (gas) and self shielded (gasless). As you might have guessed from their names, the gas shielded requires external shielding gas, while the self shielding doesn’t. Instead a gasless welder using a flux-cored wire relies on a continuous, tubular wire feed. The flux includes vapour-forming compounds that provide the gas shield needed to protect against oxidation.

While this sounds simple enough, the presence of gas makes a difference to the welding process and result – so it’s worthwhile taking the time to choose the right type for your application.

Take a look at the pros and cons of a gas and gasless welder for various factors:

  1. Location

Unlike their gas counterpart, gasless MIG welders don’t require external shielding gas. This makes them a good choice for welding out of doors or on the move, as you don’t need an external gas tank. Also, gas MIG welders are not suitable for windy locations, as any loss of shielding gas will create porosity in the weld bead and impact its integrity. So if you’re welding out of doors, gasless MIG welding may be your better bet. You don’t need to set up any windshields as the shielding gas is conveniently generated from the burning flux.


It is important to consider your location when weighing up which welding process to use.




  1. Application Position

Gas MIG welders are good to use in out-of-position applications. For example, when welding overhead or vertically upwards, the gas shielded flux cored wire has a flux coating that solidifies faster than the molten weld materials to create a shelf that holds the molten pool.

  1. Materials

A gasless MIG welder provides excellent penetration and longitudinal strength. However the result will depend on the MIG machine you choose. Some go down low enough to weld very thin materials and some don’t.

  1. Speed

Gasless MIG welders don’t have as a fast a deposition rate as those using a shielding gas. The welding speed is similar to that of arc welding.

  1. Convenience

There’s no dount that a key selling point of Gasless MIG welding is its convenience. Not only is it more portable, but you also don’t have to make your materials clean and shiny before welding. Thanks to the extra goodies in the flux, gasless MIG welders let you weld straight through surface rust, paint, galvanized surfaces and so on. This makes it a good option for industry applications. Also there’s no need to rent a gas cylinder.

  1. Fumes

You might notice gasless welding creates more fumes, but this is easily handled with the right protection.


The bottom line?

A gasless MIG welder is a great tool to have in the workshop – convenient, easy to use and did we mention convenient? But for overall weld quality most serious welders will tell you that Gas MIG product better results. THe ideal option is to have a welder the can do Gas and Gasless and the good news is that there is a huge range of gas-gasless machines on the market these days.

Click this link to have a look at our single-phase MIG welders, most of which will do gas and gasless MIG welding.

, , , ,