MIG welding is a versatile method that uses a consumable metal electrode for the welding process.
Although shielding gas is an important part of MIG welding, there is a way to weld even without it.
Technically, you will still be providing gas to the weld pool to protect it from contamination, but the gas won’t be coming from a shielding gas tank.
In this article, I will be sharing in-depth details about how you can use a MIG welder without using gas.
So, without any further ado, let’s get right to it.
Understanding Gasless MIG Welding – Flux Core Arc Welding (FCAW)
The gasless MIG welding process is known as Flux Core Arc Welding (FCAW) or simply Flux Core. It’s a bit different from the traditional MIG welding process.
In this method, you will be using a special welding wire known as flux core wire that has a coating on the wire.
The burning of the wire will produce a cloud of gas that will protect the weld pool just like inert gas. The best part, you don’t have to carry a shielding gas cylinder around with you.
There are two kinds of wires that are used in FCAW. Gas-shielded and flux-cored shielded wires. These wires have an outer sheath covering which makes up the flux.
The flux includes metal power including alloys and deoxidizers that protects the weld pool from contamination.
While FCAW seems like a better method than gas MIG welding, it is not. It really limits the application of the welding process.
The gas-shielded flux core welding still requires the shielding gas, but the self-shielded one doesn’t. That’s why this option is preferred for outdoor welding even in windy situations.
However, because of the ease of the process, it is considered ideal for beginners.
Step-by-Step Guide to MIG Weld Without Gas
Here is a step-by-step guide that can help you MIG weld without using gas.
Step 1: Gather the Equipment
Most of the equipment will be the same. You will need a MIG welding machine and all of the accessories and consumables, except for the shielding gas.
Instead of the shielding gas cylinder or bottle, you will use a special welding wire that comes with a flux coating.
Step 2: Safety Precautions
You will need a similar protection just like the one you use for the welding process. There should be no compromise on safety.
You must wear proper welding shoes, gloves, helmets, goggles, and fire-resistant apparel. Flux welding produces intense fumes and light, so protection is a must.
Step 3: Clean the Base Metal
Before you start the welding process, you must clean the base metal to remove all signs of dust and debris.
You can use a welding brush, steel wire, or aluminum to clean the metal. You might have to use sandpaper or a grinder depending on the condition of the base metal.
Step 4: Adjust the Welding Parameters
Once the equipment has been gathered and the base metal properly cleaned, you then have to adjust the welding parameters.
Calculate the amperage you will need based on the type and thickness of the material you are going to weld.
You can use charts or online tools to calculate the approximately required amperage. Thicker material will require more amperage as compared to thinner material.
Wire-speed will also depend on the welding specifics. You can also calculate the wire speed based using charts or online tools.
There is no need for adjusting gas flow as you won’t have a cylinder or gas regulator, which makes this form of welding more convenient.
Step 5: Start the Welding Process
Once the welding machine is set, you can start the welding process. Initiate the arc to see if the machine is working properly.
Remember to take guidance from the user manual. Each MIG welder is different and might come with slightly different settings.
Step 6: Fine-Tune the Weld Settings
The charts and online tools only give you the approximate settings required for a particular weld.
You will have to achieve the precise settings by fine-tuning the device using the welder first on a piece of scrap metal.
This fine-tuning prevents any problems that you might face while welding the precious base metal and will set the weld settings accurately for a smooth welding process.
Step 7: Weld the Joints
Now it’s time to begin the welding process. Move the welding gun along the joint to create the weld.
The flux coating on the wire will automatically transform into gas to protect the weld pool and create the joint.
Adjust the welder travel speed according to the specific requirement of the welding. You might need to make a couple of passes through the same spot to strengthen the weld.
Step 8: Finishing and Cleaning
FCAW creates more spatter than gas MIG welding, which means you will have to do more cleaning afterward.
Just grind the weld joint to clean it properly and polish it to give it a clean look. Once the spatter has been cleared, the weld joint will get a polished look.
Advantages of MIG Welding Without Gas
Here are some of the key advantages of gasless MIG welding or FCAW:
- Flux core arc welding provides you with a high deposition rate, so you will be able to fill up joints much faster.
- It is known as an all-position welding process, which means it can be used in any position.
- Not all materials can be welded using this process.
- You won’t be able to see the weld pool.
- Produces more noise than gas MIG welding.
- Much more convenient than normal MIG welding, as the preparation and welding process doesn’t require shielding gas usage.
- More economical than conventional MIG welding.
- Ideal for beginners.
- Much lighter in total weight as you don’t have to carry the shielding gas bottle or cylinder around with you.
- This welding process is reliable for welding thicker metal sheets.
- Can deal with dirty or even rusty metals without much cleaning.
- FCAW produces strong welds which can be strengthened by doing multiple passes along the same spot.
- The consistent production of gas clouds on contact makes this process ideal for outdoor welding needs even in windy conditions.
Disadvantages of MIG Welding Without Gas
Just like every other method, gasless MIG welding also comes with some limitations.
- The arc initiation requires contact between the electrode and base metal. There is a risk that the process will fuse both together.
- If the gas doesn’t escape from the weld pool quickly, it can lead to porosity in the weld.
- Aluminum doesn’t work well with the flux coated welding process. The process is also weaker when welding thin sheets of metal.
- The process produces more fumes than gas MIG welding, which can be an issue if you have respiratory issues.
Can You MIG Weld Without Using Shielding Gas & Flux Core?
Well, that will be true gasless MIG welding, but unfortunately, it is not possible. Although technically, you can still make the joint, it will just be too weak and brittle and will easily break.
The gas exists for the purpose of protecting the weld pool from atmospheric contaminants. Whether you are using shielding gas or flux core method, both will release a gas cloud to protect the weld pool.
The absence of that gas cloud will leave the weld pool vulnerable to all of the contaminants which will result in a contaminated and much weaker weld.
So, although you can still weld without gas, it won’t yield a good result.
Related: What Can You Weld with a MIG Welder?
Frequently Asked Questions
Is it possible to MIG weld without using any gas?
If you are not using the shielding gas, then you can use flux-coated welding wire. The process is known as Flux Core Arc Welding. The coating has materials that produce the gas cloud to protect the weld pool from contamination.
What if you MIG weld without shielding gas?
You can use the Flux Core Arc Welding method to weld without using shielding gas. However, if you are not planning to do that then you cannot proceed with MIG welding. Welding without gas will produce a weak weld.
Is gasless MIG welding any good?
The FCAW is a very efficient and reliable welding process with tons of applications. It is very easy for beginners to learn and has tons of advantages. Read the above guide to know more details about the process.
How does a non-gas MIG welder work?
The process uses a specialized wire known as the flux-coated wire that has a hollow space in it that contains powdered materials. When burned, they form a gas cloud that protects the weld pool from contamination.
How do you set up a gasless MIG welder?
Setting up a gasless MIG welder is more convenient as compared to a gas MIG welder. You don’t have to worry about the shielding gas tank, or regulator or adjusting the gas flow, which makes the process a whole lot easier.
To sum it all up, gasless MIG welding is also a popular and reliable welding process. Though it has fewer applications than gas MIG welding and comes with some limitations, it also has plenty of advantages.
Gasless MIG welding or Flux Core Arc Welding is particularly beneficial for beginners as it is much easier to learn and get a hold of.
The above guide shares in-depth details about the welding process and its various aspects.
Still, got some questions? Drop them in the comments section below and I will get back to you as soon as I can. Happy Welding!
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