MIG Shield Gas Selectionit is extremely critical to the quality of all your soldering.
Understanding this importance led us to produce this EXCLUSIVE guide on selecting MIG Shield Gas for your projects.
After reading this guide you will understand:
- Why do we need shielding gas for MIG welding.
- A list of 10 factors that influence your choice of MIG Welding Gas.
- 03 Fundamental properties of MIG welding gas.
- 04 Basic Types of Gas MIG Welding
Ready for new knowledge? Let's go!
- Why do we need shielding gas for MIG welding?
- TEN FACTORS THAT INFLUENCE YOUR SELECTION OF MIG WELDING GAS
- THREE Fundamental Properties of MIG Welding Gas
- 1. Shielding gas ionization potential
- 2. Shielding gas thermal conductivity
- 3. Chemical reactivity between shielding gas and molten pool
- FOUR basic types for your MIG welding gas mix
- 1. Inert MIG shielding gas
- 2. Reactive MIG shielding gas
- 3. Two-part MIG shielding gas mixtures (binary mixtures)
- 4. Three-part MIG shielding gas mixture (ternary gas mixture)
- Optimal flow rate for your MIG welding gas
- Basic MIG Shield Gas Selection Guide
- Frequently Asked Questions About Selecting MIG Welding Gas
Why do we need shielding gas for MIG welding?
The main purpose of using shielding gas tosunny day meIt is to protect the welding area from gases in the air, such as oxygen, nitrogen, hydrogen, propane, etc.
Without the application of shielding gas, your weld pool will be exposed to gases and contaminants from the atmosphere.
This exposure causes some welding defects, such as: fusion defects, porosity (holes inside the weld bead), metal embrittlement and excessive spatter.
In contrast, using a suitable shielding gas produces cleaner and faster MIG welds:
- Cleaner welds are due to protection from atmospheric contaminants as mentioned above.
- Faster welds are possible thanks to the absence of interruptions between weld runs to replace contaminated electrodes (as in the case of stick welding).
TEN FACTORS THAT INFLUENCE YOUR SELECTION OF MIG WELDING GAS
The use of shielding gas in MIG welding has proven to be extremely effective.
However, the proper choice of MIG welding gas is influenced by many different factors.
We've researched and compiled the following list of 10 factors that all manufacturers should carefully consider before selecting shielding gas for their MIG projects.
Here is the list:
- Factor 1: TheMIG welding wire selection.
- Factor 2: The mechanical characteristics of the deposited weld metal.
- Factor 3: The thickness and type of joint on your workpiece.
- Factor 4: The condition of your workpiece (whether mill scale, oil or corrosion).
- Factor 5: TheMIG metal transfer modes.
- Factor 6: The welding position.
- Factor 7: The mounting conditions.
- Factor 8: The desired penetration profile.
- Factor 9: The desired appearance of your weld bead.
- Factor 10: The total cost (perhaps the most important factor of all).
A shortcut to optimal shielding gas selection is to consult your MIG wire supplier.
Give your supplier a good idea of the details of your MIG welding project so they can offer you some suitable options, taking into account many of the above factors.
Also, be sure to check out the MIG welder recommendation guide found atindoor panel welder.
THREE Fundamental Properties of MIG Welding Gas
In this part you will learn about 03 fundamental properties of MIG Welding Gas, which are:
- Ionization potential.
- Thermal conductivity.
- Chemical reactivity with the molten solder puddle.
1. Shielding gas ionization potential
The ionization potential refers to the amount of energy required to ionize the shielding gas.
Energy is measured in eV (electronvolt).
You may ask, why do we need to ionize the gas?
Well, ionization helps make the shielding gas conductive (a conductor of heat and electricity).
When the shielding gas is conductive (i.e. a plasma), it can transfer heat and electricity to your workpiece and make your MIG welding project possible.
That is all! So, in short, to do MIG welding, we need to ionize the shielding gas, for power.
Each type of gas has a different ionization potential.
- HIGH ionization potentialmeans that the gas requiresbut energybe ionized.
- LOW ionization potentialmeans that the gas requiresless energybe ionized.
One example is argon and helium, the two most common shielding gases for MIG welding.
If you notice, argon can start the arc faster than helium.
This is because it is easier to ionize argon than helium.
Argon has a lower ionization potential (15.7 eV), while helium has a higher ionization potential (24.5 eV).
2. Shielding gas thermal conductivity
Thermal conductivity refers to the ability of the shielding gas to deliver thermal energy or heat to your workpiece.
It is considered the most important consideration when you are selecting a shielding gas for your welding projects.
As with ionization potential, different shielding gases have unique levels of thermal conductivity.
This property affects the arc shape and depth of penetration.
- HIGH thermal conductivity(from helium, for example) creates awider arc zoneswindlershallower penetration.
- LOW thermal conductivity(of argon, for example) produces aminor arc area, but onedeeper penetration pattern.
3. Chemical reactivity between shielding gas and molten pool
Well, the title pretty much says it all.
Chemical reactivity here refers to the most fundamental property of the shielding gas, whether it is inert or reactive with the weld pool.
Unlike TIG welding, in MIG operations you have more usable options for shielding gas, including inert gases (argon, helium) and reactive gases (oxygen, CO2, etc.)
The main consideration here is that reactive gases are much more accessible (cheaper) than inert gases.
So if you're on a budget, you might want to use reactive gases.
FOUR basic types for your MIG welding gas mix
As mentioned above, there are two groups of MIG welding gases: inert and reactive.
The four most common types of shielding gas for MIG operations are: Carbon dioxide (CO2), Argon, Helium and Oxygen.
Each option offers unique enhancements, as well as drawbacks, to your MIG's performance.
In this part, you'll learn about each one and how to mix them together to produce the most effective shielding gas for your MIG projects.
So don't blink and make sure you follow it all the way.
1. Inert MIG shielding gas
There are many factors that go into choosing a shielding gas, especially for the MIG welding process, as you have a wider range of options.
One factor is the material type of your weld metal (Remember Factor 2 mentioned above?)
If the metal being welded isnon-ferrous(meaning it doesn't contain iron), so congratulations, becausePure inert shielding gas is your best choice.
With inert shielding gas for MIG welding, you can chooseargon or helium.
Argon is probably the most widely used inert shielding gas.
As we discussed, Argon hasLOW ionization potential, like thisLOW thermal conductivity.
This produces a deep, narrow penetration pattern that looks like a finger, which is excellent for both butt and fillet joint types.
It is also easier to start an arc using argon as the shielding gas.
Argon is widely used in MIG welding of non-ferrous metals such as titanium, copper, nickel, aluminum and magnesium.
Argon is also a basic component to mix with other gases to create binary (two-gas mixture) or ternary (three-gas mixture) in MIG welding, which will be discussed later in this article.
Everything about Hélio is loud:HIGH thermal conductivity,HIGH ionization potential, and HIGH price too.
Due to its high price, helium is often added to a mixture of gases and not used in its pure form.
In addition to non-ferrous metals, helium is also applied for MIG welding of stainless steel and aluminum, especially for parts thicker than 1 inch (25 mm).
When you use helium it can produce a wider penetration profile but not as deep as argon.
One special thing about Helium is that it can increase your productivity.
This is possible because the helium creates a hotter arc, forcing you to move your MIG gun faster (increased traverse speed) and eventually finishing your MIG welds faster.
2. Reactive MIG shielding gas
Reactive shielding gases used for MIG operations include: Carbon dioxide (CO2), Oxygen, Nitrogen, Hydrogen, etc.
Reactive gases can chemically react with the weld pool to create a desirable characteristic.
(a) Carbon dioxide (CO2)
CO2it's the only reactive gas you can use in its pure form (without any inert gas mixtures).
Thanks to this, CO2is considered the most affordable option.
CO use2As a MIG shielding gas, it provides a wide and deep penetration pattern (discussed in more detail later).
This feature makes CO2the ideal choice for MIG welding of thick materials.
However, of the 4 metal transfer modes,pure CO2it is only suitable with short circuit mode.
Furthermore, the use of pure CO2creates more spatter than when mixed with other gases.
Therefore, its use is recommended for projects with low aesthetic requirements, such as a car body.
This is the basics for CO2!
The following content goes a little deeper into why CO2provides a wide and deep penetration pattern.
CO2it only becomes reactive with the molten solder puddle after being ionized.
Such a penetration pattern is possible thanks to two processes called “dissociation"eu"recombination”.
- Dissociation: In the anode region (DC+), the CO2molecule breaks down into free carbon, oxygen and carbon monoxide (CO).
- recombination: In the cathode region (DC-), which is the workpiece itself, the components released from CO2molecule recombines to form CO2. This creates a high level of energy, which leads to a wide and deep penetration pattern.
the amount of CO2used as a shielding gas can seriously affect the appearance of your finished weld.
*** HIGH level of CO2
A high level of CO2will release more free oxygen after going through dissociation and recombination processes.
This free oxygen will react with your metal alloys (silicon, manganese, iron, etc.) to form an oxide layer.
The oxide layer then floats to the surface of the weld pool and solidifies there, creating slag.
*** LOW level of CO2
On the other hand, a low level of CO2it will release less free oxygen and therefore will not create an oxide layer for the final slag to form.
Therefore, perform MIG with low CO2you can preserve all the alloying elements in your workpiece and improve the maximum tensile strength of your finished MIG welds.
(b) Oxygen (O2)
Oxygen (O2) will certainly react with your melt pool to form oxides.
Therefore, it should be kept at low levels (1-9%) and should be mixed with an inert gas.
OU app2Helps improve weld pool flow, arc stability, and weld appearance.
O2It's good forMIG Welding Stainless SteelyMild Steel MIG Welding.
Esprohibiteduse the2with non-ferrous metals such as copper, aluminum, magnesium, as it may cause oxidation.
(c) Hydrogen (H2)
Hydrogen (H)2) is also used in small amounts (1-5%) and is mixed with an inert gas (probably argon).
It has HIGH thermal conductivity which helps create a smoother puddle and allows for faster travel speeds.
Hydrogen can be applied in high temperature design for austenitic stainless steels.
(d) Nitrogen (N2)
Nitrogen (N)2) is often used for MIG welding of stainless steel pipes, primarily as a return gas.
It can also be mixed with Argon and used as a shielding gas for MIG projects on stainless steels.
3. Two-part MIG shielding gas mixtures (binary mixtures)
Two-part MIG shielding gas mixtures, also known as binary mixtures, are typically the combination of: argon + helium; Argon + CO2; or Argon + O2.
(a) Argon + Helium
The mixture of Argon and Helium is normally applied toAluminum MIG Welding, nickel and stainless steel.
Axial sputtering and pulsed sputtering transfer are the preferred metal transfer modes for this mixture.
The addition of helium to these binary gas mixtures improves the fluidity of the molten pool and therefore increases the displacement velocity.
Helium also reduces the finger pattern found when applying pure argon, especially on aluminum.
In summary, while argon facilitates the arc and helps with the cleaning action (on aluminum), helium increases travel speed and reduces the finger-like penetration pattern.
There are two common binary mixtures for argon and helium:
- In the first place, It is75% Argon + 25% Helium. Compared to pure argon, this mixture improves the pool flow and penetration profile for aluminum, nickel and copper MIG welding.
- In second place, It is25% Argon + 75% Helium. Higher levels of helium further increase thermal conductivity, pool fluidity and broaden the penetration profile. Finally, it provides a higher scrolling speed.
(b) Argon + CO2
A mixture of argon and carbon dioxide (CO2) is good for stainless steel and mild steel MIG welding.
All metal transfer modes can be used with this gas mixture.
However, it depends on the level of CO2, the proper metal transfer mode is different
- you are CO2the content isless than 4%,pulsed spray modemust be used, especially for stainless steel.
- you are CO2the content isless than 18%,axial spray modeIs a good choice.
- you are CO2the content reachesmore than 18%,short circuit modeit is more effective
Normally, CO2the level ranges from 5% to 25% in the mix.
The addition of CO2provides better arc stability and reduces spatter than Pure CO2could cause.
But be careful, higher levels of CO2increases the possibility of splashes and burns.
Here are some common combinations for this gas mixture:
|binary mixtures||Feature||Metal Transfer Mode|
|75% Argon + 25% CO2(also known asC25)||Prevents spatter and improves weld bead appearance in mild steel applications.||Short circuit|
|80% Argon + 20% CO2|
|98% Argon + 2% CO2||Provides high fluidity of the puddle and high displacement speeds with carbon steel or stainless steel electrodes.||Axial spraying / Pulsed spraying|
|95% Argon + 5% CO2||It improves the fluidity of the puddle, with carbon steel electrodes. Suitable for thicker workpieces.||pulsed spray|
|92% Argon + 8% CO2||Suitable for carbon steel applications.||Axial spraying / Pulsed spraying|
|90% Argon + 10% CO2||Suitable for carbon steel applications. Provides a wider arc and reduces the depth of the finger-like penetration pattern.||Axial spraying / Pulsed spraying|
|85% Argon + 15% CO2||Improves sidewall fusion in sheet metal. Provides less heat and reduces the risk of burns.||Axial spray/pulsed spray/short circuit|
|82% Argon + 18% CO2||Can be used for various weld thicknesses. Produces a broad penetration pattern.||Axial spraying / Short circuit|
(c) Argon + O2
The use of the mixture of Argon and Oxygen allows to increase the displacement speed in thin materials.
This mixture is popular in stainless steel and mild steel MIG welding.
However, the level of O2used shall not exceed 5%.
Here are the 3 best mixtures of argon and oxygen:
- 99% Argon + 1% Oxygen: This mainly applies to MIG stainless steel projects. However, it produces a grayish appearance on your stainless steel.
- 98% Argon + 2% Oxygen: this can be used for both mild and stainless steel MIG applications. But this mixture creates a dull gray look on your stainless steel parts.
- 95% Argon + 5% Oxygen: This is usually used with axial spray or pulsed metal transfer spray mode. It is good for thicker mild steel parts. However, due to high oxygen levels, the base metal must be free of contaminants to prevent oxidation.
4. Three-part MIG shielding gas mixture (ternary gas mixture)
The three-part MIG shielding gas mixture, also known as a ternary gas mixture, comprises at least 3 different gases, one of which is inert (eg argon).
Ternary gas mixtures are very popular for MIG welding of stainless steel, carbon steel and even nickel alloys.
Here are the 4 best ternary gas mixtures that you can find in many stores:
- 90% helium + 7.5% argon + 2.5% CO2: This mixture is perfect for short circuit transfer mode in stainless steel MIG welding projects. The high level of helium provides excellent fusion and travel speed. In addition to short circuit mode, it is also used in pulsed spray mode for stainless steel and nickel materials thicker than 1.6mm.
- 55% helium + 42.5% argon + 2.5% CO2: this mixture provides a cooler arc, suitable for pulsed spray transfer mode. It can also be used for axial and short circuit spray transfer mode.
- 38% Helium + 65% Argon + 7% CO2: this mix allows for a wider penetration pattern and is a good choice for short circuit transfer in mild steel MIG welding.
- 90% Argon + 8% CO2+ 2% O2: This mix greatly reduces splashing (due to the high inert gas content). Works well with short circuit, pulsed spray and axial spray transfer modes for MIG welding on mild steel projects.
Optimal flow rate for your MIG welding gas
The ideal flow rate for MIG welding gas depends on 4 main factors:
- Weld geometry:Flat surfaces will require a higher gas flow than rough materials as the gas spreads out more.
- Travel speed:Higher speed MIG welding simply requires more gas to shield the weld pool.
- Electric current setting:Higher current settings require more volume of shielding gas, especially helium, to completely cover the weld pool.
- Metal transfer mode for MIG welding:The 4 main variations of MIG welding have different requirements for shielding gas flow.Short circuitypulsed spraythe modes need about20 pies 3/hr.globular transferdemands on30 pies 3/hr, whilespray transferworks well with more40 pies 3/hr.
Basic MIG Shield Gas Selection Guide
As mentioned above, the choice of MIG shielding gas depends on up to 10 different factors.
Shielding gas selection is also a crucial step in setup.Correct MIG welding parameters.
So this is an important but difficult decision to make.
We've compiled a table below, which we hope will reduce complexity and help you make a decision faster.
|material base||type of electrode||metal transfer mode||MIG Shield Gas Selection|
|Carbon steel||ER70S-3 ER70S-4 ER70S-6 E70C-6M||GMAW-S or STT||100% CO275-90% Argon + 10-25% CO2|
|Axial spray or GMAW-P||82-98% Argon + 2-18% CO295-98% Argon + 2-5% O290% Argon + 8% CO2+ 2% O2|
|light alloy steel||ER80S-Ni1 ER80S-D2 ER100S-G ER110S-G E90C-G E110C-G||GMAW-S or STT||100% CO275-80% Argon + 20-25% CO2|
|Axial spray or GMAW-P||95% Argon + 5% CO295-98% Argon + 2-5% O2|
|Aluminum||ER1100 ER4043, ER4047 ER5183, ER5356 ER5554, ER5556||Axial spray or GMAW-P (not GMAW-S)||100% argon 75% helium + 25% argon 75% argon + 25% helium 100% helium|
|austenitic stainless steel||ER308LSi ER309LSi ER316LSi||GMAW-S or STT||98-99% Argon + 1-2% O290% helium + 7.5% CO2+ 2,5% O255% helium + 42.5% argon + 2.5% CO2|
|Axial spray or GMAW-P||98-99% Argon + 1-2% O298% Argon + 2% CO297-99% Argon + 1-3% H255% helium + 42.5% argon + 2.5% CO2|
|nickel alloys||ERNi-Cr3 ERNiCrMo-4 ERNiCrMo-3 ERNiCrMo-10 ERNiCrMo-14 ERNiCrMo-17||GMAW-S or STT||90% helium + 7.5% argon + 2.5% CO275% Helium + 25% Argon 75% Argon + 25% Helium|
|Axial spray or GMAW-P||100% argon 75% helium + 25% argon 75% argon + 25% helium 97-99% argon + 1-3% h2|
|duplex stainless steel||2209 2304||GMAW-S or STT||90% helium + 7.5% argon + 2.5% CO298-99% Argon + 1-2% O298% Argon + 2% CO2|
|Axial spray or GMAW-P||75% helium + 25% argon 75% argon + 25% helium 100% argon 100% helium|
|Copper and nickel alloys 90/10||ERCuNi type 70/30||Axial spray or GMAW-P (not GMAW-S)||100% argon 75% helium + 25% argon 75% argon + 25% helium|
|copper leagues||ERCu (deoxidized)||Axial spray or GMAW-P||100% argon 75% helium + 25% argon 75% argon + 25% helium|
|Silicon bronze and brass||ERCuSi||GMAW-S ou STT Axial sputtering ou GMAW-P||100% argon|
|aluminum bronze||ERCuAl-A1 ERCuAl-A2 ERCuAl-A3||Axial spray or GMAW-P Limited GMAW-S||100% argon|
That's the end of all the fundamentals about MIG Shield Gas and how to choose the right one for your project.
After reading this article, we hope you understand the factors that influence MIG gas selection, key shielding gas properties, and certain types of gas/gas mixtures.
- Welding Principles and Practices (Fifth Edition) – McGraw Hill Education. Edward R. Bohnart. 
- Gas Metal Arc Welding: Product and Procedure Selection – Lincoln Electric. 
- gas metal arc welding. . . . Wikipedia, the free encyclopedia. Retrieved on September 28,
- How to weld with wire feed. Welding seat. Accessed September 28, 2020.
- Fundamentals of Shielding Gas for MIG Welding. Bernardo. Accessed September 28, 2020.
- The fundamentals of MIG welding fumes. Tip of the American Torch. Accessed September 28, 2020.
- MIG welding gases. GoWelding. Accessed September 28, 2020.
Frequently Asked Questions About Selecting MIG Welding Gas
1. Can you MIG weld 100% argon?
2. Does MIG welding require gas?
3. How to stop spatter in MIG welding?
4. What is the best gas for MIG welding of carbon steel (low carbon steel)?
5. What is the best gas to use for stainless steel MIG welding?
6. What is the best gas for aluminum MIG welding?
7. What is the best CO2 - Argon mixture for MIG welding?
What gas should I use for MIG welding? ›
The most common of the reactive gases used in MIG welding is Carbon Dioxide (CO2). It is the only one that can be used in its pure form without the addition of an inert gas. CO2 is also the least expensive of the common shielding gases, making it an attractive choice when material costs are the main priority.What should argon gas be set at for MIG welding? ›
A good starting point is 20 to 25 CFH. Keep an eye on the weld surface and the area around weld toes. If you notice porosity, increase the flow.What is the best gas for MIG welding mild steel? ›
There are two main industrial gases used by welders for MIG welding mild steel - 100% carbon dioxide (CO2) or 25-75 mix of CO2 and argon (known as NMAC25T in Simcoe Gase's lineup of speciality welding gases).What voltage and wire speed should I set my MIG welder? ›
The voltage and wire feed speed vary though. A 0.024-inch wire would operate at 13 to 15 volts (electrode positive) with a wire feed speed of 130 to 160 ipm, whereas the 0.30-inch solid wire would require 15 to 17 volts and 75 to 100 ipm wire feed speed.How much does a bottle of argon cost? ›
100% Argon Gas Tank Costs.
|Size||Initial Cost (full)|
|125CF||$350 to $400 (example)|
Can You MIG Weld Steel Using 100% Argon Gas? It's a question every welder will face at some point, and yes, you can MIG weld steel if all you have is pure Argon.Do you push or pull MIG welding? ›
Push or pull: Here the rule is simple. “If it produces slag, you drag,” says Leisner. In other words, you drag the rod or wire when welding with a stick or flux-core wire welder. Otherwise, you push the wire with metal inert gas (MIG) welding.What is the best argon mix for MIG welding? ›
If you're going to be MIG welding, there are two main gases that are used: pure argon and an argon/carbon dioxide mix. The most common (and recommended) Ar/CO2 mix is a 75/25 ratio, with 75% of it being argon and 25% of it being CO2.Can you have too much gas when MIG welding? ›
Operating with an excessive gas flow rate can cause turbulence to occur at the base of the welding gas nozzle. Turbulence means air gets sucked into the flow of welding gas. This can result in the appearance of porosity, inclusions, and spatter – all the issues that welding gas is meant to prevent in the first place!What is the easiest metal to gas weld? ›
Steel is the easiest metal to weld, hence why it is the most popular form of metal for welding. In fact, carbon steel is the cheapest metal to buy on the market. Steel welding often involves stick welding, MIG welding, and tig welding.
What is the best gas pressure for MIG welding? ›
The ideal pressure range for most standard MIG welding jobs is between 3 to 8 PSI.How do I get good MIG welds? ›
- Clean, Clean, Clean. ...
- Get a Great Ground. ...
- Keep Your Stickout Short. ...
- Use Both Hands. ...
- Listen To Your Welder. ...
- Keep The Arc Up Front. ...
- Match Drive Rolls, Gun Cable Liner, Contact Tip to the Wire Size. ...
- Push or Pull.
Since welding requires a lower frequency and more precise handling, most MIG welders operate with DC rather than AC.How many amps is a good MIG welder? ›
Basically, the spray transfer process requires a MIG welder in the 200+ amp category.Can you store argon bottles laying down? ›
Section 1926.350(a)(9) provides that compressed gas cylinders must be secured in an upright position, regardless of whether they are in use or in storage.How do I know what size argon bottle I need? ›
The easiest and safest way to determine the contents of a gas cylinder at your business is by checking the label. The cylinder labels will tell you everything you need to know about the gas specifications inside the cylinder, the potential hazards and safety warnings.How long will a bottle of argon last? ›
In an average goldsmith's workshop, one filling of a 10-liter bottle will last for about 6 to 12 months, depending on how intensively welding is done with the PUK.Can you MIG weld without shielding gas? ›
There's 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 Wire is actually “Self Shielding”. Self Shielding Mig Wire is a tube of metal with a flux core.Can I MIG weld aluminum? ›
Material thickness: Most reputable MIG machines can be used to weld aluminium down to 3mm thickness. To successfully weld materials thinner than 3mm, it may be neccessary to use specialist MIG or TIG welders with pulse capability. (Note: to TIG weld aluminium, you will need an "AC/DC" machine such as the 202T).Can you MIG without shielding gas? ›
“MIG,” short for metal inert gas, actually tells a lot about this method of welding. It actually requires gas for shielding: the gas involved in the welding process prevents the molten welding pool from interacting with the surrounding gases in the air.
Do you weld uphill or downhill with MIG? ›
By welding uphill you'll be able to penetrate deeper into the metal, stacking the weld up and giving it time to penetrate into the joint. For thin metal, such as on automotive welds, you can weld downhill and even do a stringer.What angle should you hold a nozzle when MIG welding? ›
In most cases, the gun should be angled slightly in the direction of motion. This is called the travel angle, and 15 degrees is a good place to start. Looking at the gun from the end of a seam, the angle of the gun to the work is called the work angle. For a butt joint, 90 degrees is ideal.What angle should torch be for MIG welding? ›
Flat position. When welding a butt joint (a 180-degree joint), the welding operator should hold the MIG welding gun at a 90-degree work angle (in relation to the work piece). Depending on the thickness of the base material, push the gun at a torch angle between 5 and 15 degrees.What is 75% argon 25% CO2 used for? ›
The 75/25 mix of Argon and CO2 is chosen most often as it delivers consistent results, ensures arc stability, maintains puddle control, and has low spatter. The mixture also allows for spray transfer. This makes the welding process easier, more productive, and yields visually appealing results.What size argon tank do I need for a MIG welder? ›
Popular Welding Gas Bottle Sizes for MIG and TIG. There are many size gas MIG/TIG tanks on the market. But the three main sizes a homeowner, or hobby welder will most likely use is the 40, 80, or 125 cubic feet (“cf”) tanks of Argon or MIG gas mixture (75% Argon, 25% CO2).Can I weld aluminum with argon mix? ›
The gas for aluminium welding can be argon or helium. These two gases are used pure or mixed. Pure argon is the most popular. However, the ionization potential and thermal conductivity of helium are much higher than for argon.Why do I get shocked while MIG welding? ›
Primary shock happens when you touch a “hot component” inside the welding machine while touching the welding case or other grounded metal. Depending on your specific machine, primary shock involves anywhere from 110 volts to 600 volts or more.Why am I getting bubbles in my MIG welds? ›
Watch your voltage / arc length. The further away the gun is from the weld site, the more likely air and gas will seep into the weld puddle causing bubbles to form which will in turn make a weak weld. Preventing porosity in your weld will overall increase the durability and purity of your weld.What are 7 common mistakes people make when they start MIG welding? ›
- No. 1: Repurposing old equipment.
- No. 2: Using the wrong MIG gun size.
- No. 3: Purchasing filler metals based on cost only.
- No. 4: Improper weld preparation.
- No. 5: Improper preheat or interpass temperature control.
- No. 6: Shielding gas inconsistencies.
- No. 7: Improper filler metal storage and handling.
- Titanium and steel.
- Aluminum and copper.
- Aluminum and stainless steel.
- Aluminum and carbon steel.
What weld is the hardest to make? ›
TIG welding is the hardest form of welding to learn for a variety of reasons. The process of TIG welding is slow and takes time to get used to as a beginner. A TIG welder requires a foot pedal to feed the electrode and control the variable amperage while maintaining a steady hand at the welding torch.What metal can't you weld? ›
Some examples of material combinations that cannot be fusion welded successfully are aluminum and steel (carbon or stainless steel), aluminum and copper, and titanium and steel. Nothing can be done to alter their metallurgical properties.What is one of the most common problems with MIG welds? ›
Wire feed speed/amperage too high - Setting the wire feed speed or amperage too high (depending on what type of machine you're using) can cause poor arc starts and lead to an excessively wide weld bead, burn-through and distortion.Should you weave when MIG welding? ›
Most welders agree that pulling a MIG weld is the easier option because you're simply drawing a straight line. You can do some weaving while pulling if you like, but it will not be as smooth as a pushed and weaved bead.What are the 3 tips to MIG welding? ›
- Keep a 1/4 to 3/8 in. ...
- For thin metals, use a smaller diameter wire. ...
- Use the correct wire type for the base metal being welded. ...
- Use the proper shielding gas. ...
- For steel, there are two common wire types. ...
- For best control of your weld bead, keep the wire directed at the leading edge of the weld pool.
MIG welding aluminium can be a lot faster than using TIG, and you can stick to your standard DC settings, so you won't need a machine with AC/DC capabilities.Do you weld aluminum on AC or DC? ›
DC is used for TIG welding Mild Steel/Stainless material and AC would be used for welding Aluminium.What should I set my MIG welder at? ›
- 30-130 amps: .023 inch.
- 40-145 amps: .030 inch.
- 50-180 amps: .035 inch.
- 75-250 amps: .045 inch.
Welding 1/4-inch steel in a single pass requires roughly 180 amps. The phrase in a single pass is the key.How thick of metal can a 110V MIG weld? ›
For example, a 140 amp, 110V welder will be fine for metal up to 1/8", but you should pay attention to the lower end of welding output. With MIG welders, that's most commonly 20-30 amps, so you want to go as low as possible with thin metals.
Is co2 or argon better for MIG welding? ›
TIG Welding requires pure Argon gas, which produces a clean weld with no oxidisation. MIG Welding requires an Argon-CO2 mixture for higher penetration and heat. The purpose of the gas in the MIG process is to protect/shield the wire, the arc and the molten weld metal from the atmosphere.Can I MIG weld without argon? ›
While it's technically impossible to MIG weld without gas, it's very possible to weld without lugging a gas cylinder and other equipment around. Self-shielding welding with flux core wire is a great option for many hobby users, and with the right welding supplies you can achieve great results!Can you use 75 argon 25 co2 to weld aluminum? ›
OK, so 75/25 doesn't work for Aluminum.Can you use a MIG welder without argon gas? ›
There's 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 Wire is actually “Self Shielding”. Self Shielding Mig Wire is a tube of metal with a flux core.Which is cheaper argon or Co2? ›
Active gases are used for Mig Welding most metals (except Aluminium and Mig Brazing, where pure Argon is used). Co2 is the lowest cost of the Active Gases, but is far from the best. Co2 produces a cooler, coarser, more spattery arc and a marginally harder weld.Can you MIG weld aluminum with 100 argon? ›
Choose the right gas: Because aluminum is a non-ferrous metal, it requires a 100 percent argon shielding gas. Flow rates of 20 to 30 cubic feet per hour are recommended. What process should you use? When MIG welding aluminum, the desired mode is spray transfer.Are gasless MIG welders OK? ›
A gasless MIG welder produced more smoke and fumes, meaning it's not a great choice for indoor welding. You can't weld all material with a gasless MIG welder. Flux core wire can be damaged if not handled properly. The MIG welding machine you use must be able to support flux core wire welding.Is gasless MIG as good as gas MIG? ›
The answer? Gasless. Gasless (flux-cored) welding creates a lot more fumes than when using a shielding gas, thanks to all the things in the flux that work to protect the weld. That's why gasless welding is much better for outdoor use.What is the best gas for MIG aluminum? ›
The two gases used for MIG welding aluminum are argon or helium. They can be used in their pure form, or as a mixture of both. Typically, pure argon is the most popular of these gases to use as a shielding gas in MIG welding aluminum. Pure argon is commonly used up to a sheet thickness of approximately 12.5mm.What is the best gas for aluminum MIG welding? ›
Welding gas for aluminum
The most common gas used for MIG welding aluminum is 100% argon. This gas allows you to get into a spray transfer or pulsed spray transfer mode easily for aluminum due to its low ionization value. Another benefit of 100% argon gas is that it can also be used for TIG welding aluminum.
Can you MIG weld aluminum? ›
Material thickness: Most reputable MIG machines can be used to weld aluminium down to 3mm thickness. To successfully weld materials thinner than 3mm, it may be neccessary to use specialist MIG or TIG welders with pulse capability. (Note: to TIG weld aluminium, you will need an "AC/DC" machine such as the 202T).Is gasless MIG better than stick welding? ›
Starting off with gasless MIG welding, this process is perfect for both thin and thicker sections and is faster than stick welding as it is semi-automated, however, it has a more expensive setup cost and more variables that can potentially cause downtime if not setup correctly.Can any MIG welder use flux core wire? ›
Most MIG welders are designed to be compatible with flux core wire, however, some MIG welders may not mention this. If your MIG welder does not say, it can most likely weld with a flux core wire with a few changes to the machine.