Gas vs Gasless Mig Welding, which is best? is a conversation I have with customers on the phone on an almost daily basis.
Firstly, let’s clarify that “Gasless” Mig is not actually gasless, because there is no such thing as gasless mig welding. The weld pool has to be protected from the oxygen in the air and this is done by displacing the air with gas!
So called “Gasless” Mig Wires are actually “Self Shielding”.
Self Shielding Mig Wire is a tube of metal with a flux core. As the welding arc melts the wire it also burns the flux, this produces a gas shield around the welding process. So NOT “Gasless”.
Secondly, I’m going to put my cards on the table! I’m not the Worlds biggest fan of Self Shielding Mig Wire!
OK so it has some uses, but it produces a fierce arc that’s not much use on steel thinner than around 1.2mm and as for car body welding, well if a mig welder supplier tells you their machine can weld car body thickness steel without gas GET THEM TO DEMO IT!!!
Self Shielding Mig Wires also produce a LOT of nasty smoke, so are best used in the open air. And that really is the only place I would advocate using self shielding wire, in the open air and even then, only when its too windy to use solid wire and gas.
Self shielding mig wires were first developed in the USA for use on the vast prairie farms of the mid west. A small hand held mig welder was developed that would operate off a deep cell, 24v Tractor battery. This welder was part of a tool kit carried by the farmer and used to carry out on the spot repairs to gates etc out in the fields.
Self shielding mig wires found their way into the UK DIY welder market in the 80’s, before disposable gas cylinders became available.
By far the most common and best way to use a Mig Welder is with solid wire and a cylinder of gas. With this system, the Mig Welder pours gas over the weld pool as you weld, thus keeping Air/Oxygen from contaminating the weld.
Solid Wire + Gas is easier to use and produces better quality welds
I’ve written a separate Blog article called:
What Gas do I need for Mig Welding and Tig Welding which you may find useful
In my opinion, if you have a Gas/No Gas Mig Welder you should always use it with Gas, unless you absolutely have to use self shielding wire.
I personally, would prefer to protect the work area from wind with screens etc than use self shielding wire, but as I said earlier, I’m not a fan 🙂
We offer a full range of Mig Welding Wires for most materials, including Solid and Self Shielding wires for steel.
No, a Mig Welder will be designed to either use Wire with Gas, Self Shielding (gasless) Wire, or both (Gas/No Gas).
The difference lies in the Polarity of the Torch.
To use Self Shielding (Gasless) wire, the Torch needs to be NEGATIVE (-).
To use Solid Wire with Gas the Torch needs to be POSITIVE (+).
A machine that can operate with both Solid Wire + Gas AND Self Shielding (gases) wire will have a way of quickly and easily changing the Polarity. These machines are normally marketed as “Gas/No Gas” Mig Welders.
If you’re not sure what type of Mig Welder would best suit your needs, get in touch, you can write via our Contact Us page, or phone and ask for me! (numbers at the top of this page)
I hope you found this useful.
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