There are various kinds of welding machine types available when one needs to join metal. One of the most common types nowadays is the MIG welder. MIG welders traditionally feed a solid piece of wire through the welding gun which is then melted by extreme heat created by the electrical arc. While this happens a shielding gas is sprayed out of the welding gun nozzle to protect the molten metal and keep it free of dirty or weakening particles in the air.
Many are wondering “can you use a MIG welder without gas?” There is a long and short answer to this question. The short answer is yes, but it changes the material required to do the job. Let’s discuss the specifics of MIG welding without gas, what the differences are between gas and no gas, and how to properly go about the job!
Mig Welding vs No-Gas Mig Welding
MIG welding traditionally uses gas because it creates a good shield around the drying weld joint that prevents bad particles in the air from binding with the metal and making it weaker. It’s very necessary to keep the metal as pure and clean as possible when welding with a quality MIG welder because those dirtied joins at the very least result in a do-over. Worst case scenario sees your finished work falling apart while in use. That being said, gas is not the only way to protect your welds from unhelpful particles.
Welding without gas is done by way of a different kind of wire. The wire is hollow inside and contains something called flux. This flux either runs to the surface of your weld pool, creating a semi-hard layer of protection, or it burns and releases a gas that immediately surrounds your work, thus providing the same protection. There are actually certain situations where using flux over gas is highly preferable, not just an alternative.
The most obvious situation is if you are forced to weld outside on-site and there is wind present. If you MIG weld with gas in these conditions the wind will simply remove your gas cloud from your work, exposing it to the particles you are trying to avoid. Using flux that creates a layer atop your work deals with this problem very effectively. The techniques used in the welding process remain more-a-less the same.
How to Use a Mig Welder Without Gas – the Basics
1. Safety First
Welding is by nature a dangerous affair and requires safety equipment in order to be safe. The arc created when welding is extremely bright and emits UV rays. As such, a welding mask is a non-negotiable. This mask will protect your eyes from the light and your face from the UV rays as well as any stray sparks flying in your direction.
When welding you are literally heating metal to its melting point and as such need to be very careful not to touch surfaces you just welded. In addition to the helmet you also need to wear some welding gloves and a welder’s apron. All your exposed skin needs to be covered so that it is protected from the UV exposure as well as sparks.
2. Metal Preparation
It is vital that the metal you are binding is as free and clear of rust, dirt, paint, and other such things. The cleaner the surface, the better the weld. Use some steel wool or an angle grinder to properly clean your metal before welding it.
3. Equipment Preparation
The first thing you want to do is change out the standard wire rollers in your welding gun for flux-specific rollers. These are gentler on the wire which is needed as flux is hollow.
Once that’s done check all your connections to your machine, power source, grounding clamp, and welding gun. Ensure everything is in good order and safe to use.
You also need to set your polarity to negative. Ensure there is no left over weld material on your contact tip or around your welding gun.
You also need to make sure you have suitable tension on your wire line. It needs to be tense but not so stiff that the rollers stop working.
4. Wire Selection
The first thing to keep in mind if you’re MIG welding without gas is that of course, your wire needs to be flux wire that is used in flux-core arc welding!
If you intend on welding standard steel of medium thickness or in that general range, E71T-11 is the versatile wire type you are looking for. Try out a thickness of around 0.030 as this is for most standard weld thicknesses.
If you intend on MIG welding stainless steel without gas, I’d suggest going for a slightly thicker wire such as a 0.035.
If you plan on welding aluminium without gas try out a thinner wire, perhaps a 0.028. Aluminium is thin and thicker wire may pose the threat of burning through the metal.
The best way to get these setting right is good old-fashioned trial and error. Your welding box will have a loose guide to help you figure out the basics based on things such as how thick the metal you are welding is, but these are rough guides that will only really get you in the general ballpark of what you will need. The rest is up to you to try, set, and re-set as you go along.
6. Working Position
This rests mostly on personal preference. Situations may dictate your position for you, such as needing to weld over-head because what you’re welding is above you and cannot be moved. But whatever the position, make sure you are comfortable and have full control of the welding gun, and freedom to move along your work area. Ensure the space you are working in is free of any obstructions that could get in your way mid-weld.
If at a table, try crossing your weak arm in front of you and leaning the gun over your wrist. This gives you both stability and control as well as freedom to move along as you need to.
Learn how to use a MIG welder correctly for the best outputs. MIG welding without gas definitely has its place in the world and workshop. It can also be slightly cheaper as you don’t need to purchase and refill gas. Additionally, it means you don’t have to cart a gas canister around when needing to weld. Be sure to give both kinds of MIG welding a shot and see what best suits your common situations and preference. Happy welding!
Brent lives in Wisconsin and is a woodworker, custom cabinetmaker, interior consultant, and a freelance writer who got the opportunity to write several magazine articles for different publications on home … Read More