Can You MIG Weld Without Gas? Find out …

By Ben Norton / December 26, 2019
Can You MIG Weld Without Gas Title Image

Are you turned on by the idea of MIG welding?

But put off when you think of buying, carrying around and handling a cylinder of shielding gas?

You’re not sure how to get it all set up. It all just sounds too complicated.

You’ve seen a welder that says it’s a gas less MIG welder. And now you’re intrigued and want to know more.

Can You MIG Weld Without Gas? You Ask Yourself.

The short answer to your question is No.

All MIG welding And really all the types of welding uses some form of gas to protect the weld puddle.

But the good news is that the gas used doesn’t have to come from a separate high pressure gas cylinder. Or gas bottle or tank of gas.

The gas needed can come from the welding wire itself.

Flux Core Farm Welding
Flux Core Farm Welding

Why Does MIG Welding Need Gas?

The gas in MIG welding is called shielding gas. It’s needed to protect the hot molten metal in the weld pool.

Without shielding gas protection you’d have a brittle weak weld. And holes in your weld called porosity.

Porosity Example
Porosity Example

Porosity weakens your welding and cause your weld to fail over time.

Research the term MIG and you’ll find it stands for metal inert gas.

You see, even the meaning of the term MIG tells you that the process of MIG welding needs gas. Inert gas from somewhere.

Related document



MIG welding With a Gasless MIG welder

But, I hear you say. I’ve seen MIG welders advertised and sold as gasless MIG welders.

Yes, that’s true. And it’s confusing isn’t it? Because you’ll see those welders described as gasless MIG welders.

And it’s true you can’t plug in or use a separate tank of compressed inert gas with those welders.

But it’s not true to say that gas isn’t used in the welding process.

The shielding gas is created by the melting of the flux core wire.

And those welders use and are flux core welders. As they only use flux core wire to weld with.

How Does a Flux Core Only Welder Weld without Gas?

You’ll find that you can’t connect up a Flux Core only welder to a compressed gas cylinder.

Flux Core only welders are convenient to use. Because armed with your Flux Core welder, somewhere to plug it in. And some gasless flux core welding wire you can weld.

This is because flux core welding wire is formed like a tube.  The welding metal is on the outside of the tube and the inside is filled with something called flux.

Inside Flux Core Wire
Inside Flux Core Welding Wire

It’s where the term flux core comes from. The wire has flux at its core.

And it works this way.

As you weld with the flux core wire, the wire melts into the weld puddle.  A gas forms from the flux in the wire’s core. That gas covers the weld puddle and protects it from the surrounding air.

There is gas. The flux in the flux core welding wire’s core makes the gas.

And you don’t have to buy and use a compressed gas bottle to weld with.

Want to find out more about flux core wire? You should read this post.

Why Are Flux Core Only Welders Described as Gasless MIG Welders?

Because the phrase MIG welding is so popular. And these welders are cheaper than true MIG welders, so they catch your eye.

A true MIG welder will use a cylinder of compressed gas. A MIG welder uses and feeds solid MIG wire. This wire has no hollow core.

And that wire has to be shielded with separate high pressure gas.

MIG Welders that can Weld with No Gas

There are MIG welders that you can weld with using the MIG process. And these welders can also weld flux core.

And so when you’re using these MIG welders in their flux core welding guise. You can do without the shielding gas bottle and just feed gasless flux core wire.

The gasless flux core wire you use does not need any separate bottle of shielding gas.

There are some MIG welders sold and set up to use the flux core welding process. 

They are MIG capable. But to turn them into MIG welders you buy a kit that upgrades the welder so that you can use a compressed gas bottle. And weld MIG.

What can you weld with a Gas less MIG Welder?

You’ll find that ‘gas less’ welding with flux core welding wire has some limits.

It’s a ‘hotter’ process. And that means that a flux core only welder isn’t for welding thin mild steel.

You’ll burn through your steel.

Flux core wire will weld mild steel and galvanized steel. And stainless steel at a pinch. With the right kind of wire. 

You can find out about welding stainless steel with gas less flux core here.

You won’t be able to weld Aluminum as there is no such thing as gas less flux core Aluminum wire.  You can find out why here.

But What if You Want to Do MIG Welding Without Gas?

You can’t.

And if you have bought or have loaned a true MIG welder.

One that’s designed to feed shielding gas. 

And it’s loaded with solid MIG welding wire.

That wire needs shielding gas.

And if you run your MIG welder gasless with this set up all you’ll get is a weld that is poor. Fails quickly. And is porous – has holes in it.

You’ll be wasting your time.

Instead find out if that MIG welder is capable of working with gasless flux core welding wire.

Then get yourself some gasless flux core welding wire.

Follow the instructions to set your MIG welder up for flux core and weld away.

Understand though the limitations of no gas flux core welding. It welds thicker mild steel or galvanized steel. Or stainless steel with specialized flux core wire.

And you’ll do great.

Last Words

And now you know more about no gas MIG welding. And you’ve the answer to your question: Can you MIG weld without Gas?

You know what a gasless MIG welder really is.

And it’s for when you’ve thicker mild steel to weld.

Than you’ll have the courage to try welding flux core, with some gasless flux core welding wire.

Related Articles