MIG welders typically come in two different types – gasless or, well, with gas. It can all get quickly confusing when you are trying to determine whether your MIG welder is a gas welder or not, especially if you are a beginner in the world of welding.
It can get even more confusing when you realize you can also get certain wires that produce the effect of a gas welder, making you question whether you need a gas welder, to begin with.
Luckily for you, we have all the answers. In the article, we are going to be answering all of your gas-related MIG welder questions.
Does a MIG welder need gas?
It depends! If you have a gasless MIG welder, then, no, your MIG welder does not necessarily need gas. However, if you are in possession of a MIG welder that does use gas, then yes, this welder needs gas.
As confusing as that all sounds, it is pretty straightforward. Gasless MIG welders don’t need gas and any other MIG welder does! That being said, there may well be a time when you are using your gasless MIG welder and you realize that perhaps gas would come in handy right now. In this instance, you may start kicking yourself that you didn’t spring for the welder with a gas shield.
However, luckily for you, you can fix this by adding in a specific welding wire! If you use flux core welding, wire then it will do the job of a gas shield without needing gas! This makes it the perfect fix for those people who don’t typically find the need for a gas shield but may require it every once in a while.
Why do MIG welders need gas?
MIG welders need gas for several reasons. First and foremost, it can protect the welder and the workpiece from the extremely hot arc. This can stop the arc from causing damage and contamination to your work.
As well as this, it is also absolutely vital that you use shielding gas as a way to prevent the weld pool from coming into contact with the air. The air, as we know, contains the particles oxygen, hydrogen and nitrogen. As helpful as they are for humans, they can cause issues in your welds such as holes in your weld bead (also known as porosity, and excessive spatter. In turn, this could result in you having to remove the whole weld and start again.
How do you tell if a MIG welder is out of gas?
There are some important tell-tale signs you should look out for when you are welding to be able to tell if you are out of gas. These are any holes that form in your weld beads such as pinholes and wormholes. They can be a sure sign that oxygen, nitrogen and hydrogen have come into contact with the bead. You can also keep your eyes peeled for any small air bubbles that form in the weld puddle.
Another sign that you may be out of gas in your MIG welder is the appearance of more splatter than usual. Excess spatter can be a sign that the weld has been exposed to oxygen, as a result of the gas shield failing. Lastly, if you notice any smoking or more sparking than usual, then it may be worth checking your gas as it can sometimes be a sign that it is low or has run out.
To prevent this, it is a good idea to assess how long your welding job is likely to take you and choose a gas that can cover this. You may also want to check that you have your flow rate in the correct setting.
Keep in mind that, to work out how long you can expect your gas to last, you can complete a simple equation. Simply take the volume of the gas cylinder and divide it by the flow rate you are using. For example, argon gas with a volume of 40 cubic feet used at a flow rate of 10 cubic feet will last for around 4 hours.
Can you use gasless wire in a gas MIG welder?
In theory, you can use a gasless wire (lux core wire) in your Gas MIG welder, but it is likely to be pointless. The job of gasless wire such as flux core wire is to provide self-shielding. This is used in gasless MIG welders as a way of protecting the weld bead without the need for separate gas canisters with argon and such-like.
To use a self-shielding wire such as a gasless wire in a welder that is already producing a gas shield will render one or the other redundant. Of course, if it is the only wire you have available then it is fine, but seek out the instruction manual first to see if it is suitable.