Gas-less MIG Welding is it any good?
Are you curious about a welding? Have the words Gas-less MIG caught your eye?
If you are looking to start welding or just want to carry out a simple repair set-up costs are a big consideration. From repairing gates and garden furniture to tackling DIY metal projects, gas-less MIG is a good entry point into the world of welding.
Welding as I’m sure you might be aware. Is a process used to join two or more pieces of metal by applying heat to fuse them together. Unlike other joining methods such as soldering or brazing, welding melts the base metals to form a strong, permanent bond. Depending on the Process you chose, welding is generally made up of three elements, Power (Electricity), A filler Material (Wire) and Shielding Agent (Gas).
Gas-less MIG—also known as flux-cored arc welding (FCAW)—uses a special type of wire filled with a flux, eliminating the need for a separate shielding gas. This is what makes it different.
In this blog post, we’ll break down the Pro’s and Con’s of gas-less MIG welding—how it different, what you’ll, where it works and where it falls short.
Ultimately, is it really worth it?
So, what is MIG Welding first and foremost. MIG Welding Stands for Metal Inert Gas Welding.
MIG welding works on the following principle. Using electricity, the machine produce an electrical arc which is created between an end of the wire and the parent metal that’s being welded. The electrical arc is very powerful and melts the filler wire and subsquently the base metal which is all then fuses into the joint and a weld is created.
Modern MIG welding machines use a spool of wire which is continually fed through the machine. Which meets in the MIG Welding Torch or GUN!
At the same time, a shielding gas (typically argon, carbon dioxide or a mixture) is fed into the back of the machine and eventually into the torch via a Solenoid. When you pull the trigger Wire comes out of the machine alongside inert Gas. The gas, which is critical to the welding process protects the weld pool from contamination. That contamination is typically caused by oxygen in the atmosphere. Being inert - it’s not flammable, breathable or reactive - it blocks Oxygen from reaching the weld pool making sure fusion between the base metal and welding wire can take place.
Wire Comparison. (Top) Solid MIG Welding Wire (Bottom) Flux Core Wire
What makes it Gas-Less?
Well, being gas-less isn’t truly accurate. What they mean by Gas-less is that is doesn’t require an additional gas bottle of Argon and Co2 plumbed into the back of the machine.
Instead, you insert a wire into the machine which is different to the solid wire used in MIG Welders that use a gas bottle. This wire is actually hollow and within the wire is a Flux Powder. When you start welding, the wire melts and the flux burns releasing a shielding gas that protects the weld from contamination.
Therefore, you no longer need a gas bottle.
So, really Gas-less MIG Welders are just about the wire you put in the machine. This wire is called a Flux Core Wire. For those who like the proper names it’s called flux-cored arc welding (FCAW).
Why are gasless MIG Welders Cheap?
You might have seen a fairly big price difference in MIG Welders and Gasless MIG Welders. Why is this, I hear you ask?
Well, if the supplier is selling a Gas-less MIG Welder cheaply, it is likely it doesn’t have a solenoid. A solenoid is the critical part that makes MIG Welders what they are. When you pull the trigger the solenoid valve magnet opens, firing in shielding gas (Argon & Co2). When you release the trigger the solenoid closes stopping the gas-flow.
Being a more complicated electrical part these are not included in some Gas-Less MIG Welders reducing the cost of the item. However the supplier can provide you with a machine which continually feeds a wire spool out.
Benefits of Gas-less MIG Welding (Flux Core Wire).
There are benefits of using a Gas-less MIG Welder or Flux Core wire. Its main application is in large industrial applications where people might be in drafty warehouses or outside. Where using a gas bottle is not practical or efficient. Other considerations are;
Cost - Gas-less MIG Welders are cheaper than a fully fledge Gas MIG Welding Option. This is great for small DIY Jobs that you might find about the home.
Portability - You don’t need to lug around a gas bottle with you if working off-site.
Save money on a gas bottle - We use Hobby weld gas bottles which are lower cost but this can still add up. Having a gas-less (Flux Core Wire) options means no deposit, no paying for gas.
Works Well Outdoors - If you operate in Windy or drafty spaces. Flux Core Wire delivers a shielding gas straight to the weld pool meaning no chance of the gas being blown away.
Disadvantages of Gas-less MIG Welding (Flux Core Wire)
More spatter Produced - Flux core welding creates more sparks, fumes - which means more cleanup.
Slag Removal - Flux Core Wire Welding produces a Slag, much like MMA Welding Processes do. this needs to be removed post welding.
Limited to certain materials – It’s not ideal for very thin metals.
More fumes – The Flux creates smoke, so good ventilation or proper PPE is essential, especially indoors.
Higher wire cost – Although the machines are cheaper. The spools of wire Flux-cored wire can be more expensive per roll than solid MIG wire.
Can I put Flux-Core Wire in my MIG Welder?
Solid MIG Welding Wire. Copper Coated 0.6mm and 0.8mm thick.
Yes, if you own a MIG Welder which has used a gas bottle. You can certainly use a flux core wire to weld. It would save you having to buy a gas bottle.
If you own or Brought a gas-less MIG Welder but wanted to use a gas bottle. You would have to check there is a gas inlet for you to plum in a gas bottle. If not this machine is just for Flux Core Wire.
Gas-less MIG Welding (Flux Core Wire) vs MMA Welding?
Some people will see the similarities of MMA Welding and Flux Core Wire Welding. On the face of it, Flux Core Wire is like MMA Welding but simpler?
For those unfamiliar with MMA Welding. it stands for Manual Metal Arc Welding and uses Electricity to melt a Flux coated metal rod. The end of the rod burns along with the flux which releases a gas that shields the weld puddle from contamination. A lot of people find MMA Welding challenging at first as it’s about the operators skill and requires practise.
However, it’s main benefits which is attractive to users is its low set-up and running costs. The challenging nature of MMA Welding sometimes put’s people off using this process. Plus it is not suitable for very thin (1.5mm / .9mm thick) material.
You could say, Flux Core Wire or Gas-less MIG Welders are a bit of a happy medium. Offering Low cost welding with simplicity of operation.
So, is it any good? LETS COMPARE!
You ultimately have to decide for yourself. Below we have provided example of joinery that use a Flux Core Wire compared to a MIG Welder that uses a gas bottle.
Flux Core Wire
Spot Welding
Weld with Slag on
Weld with spatter / slag removed
A big difference you will notice is the amount of spatter produced by Flux-Core Wire. Although you a reduce this with anti-spatter spray the process still produced spatter which needs to be removed via grinding.
Gas MIG Welding (With a bottle)
Work piece spot welding / tacked up. Limited Spatter.
Work piece welded up.
Work piece afterwards. Very little spatter.
Gas-Less MIG Welding Top tips?
if you decide that flux core wire is the right options for you well that is ok. Generally speaking we found that the majority prefer welding with a shielding gas coming from a gas bottle. It’s easier to see what you are doing - due to the lack of smoke and overall reduces the amount of cleaning up.
Some tips to help you with your Gas-less MIG Welding.
Using a lot of anti-spatter spray before welding
Use a Wire Wheel an angle grinder to clean up the joins.
Use proper Personal Protect Equipment as it produces more smoke and heat than the gas bottle option.
You might find you have to increase the wire feed speed more than normal as the wire metals faster being hollow.