Whether you are repairing an exhaust or doing bodywork on a car, it's important you know what type of welding is needed for the job. What are the differences between MIG vs. TIG welding, and which should you use? In this guide, we evaluate TIG vs. MIG welding to help you decide.
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MIG Vs. TIG Welding: Key Differences Explained
Strength
The strength is a significant factor between TIG welding vs. MIG. TIG is going to produce a narrower, more focused arc that penetrates metal better, allowing the weld to be stronger. Because there should also be fewer defects with the TIG beads, you can count on the joint to only get stronger.
Don’t get the wrong idea about TIG vs. MIG welding strength. MIG welding doesn’t provide a weak bead. As you decide between the TIG vs. MIG welder, you see that both can produce a strong weld when used correctly. Just make sure you invest in good equipment and materials to ensure the strongest weld is applied.
Diversity
Figuring out when to use a MIG vs. TIG welder comes down to the job you are performing. MIG welding is great for working with large amounts of filler materials. It can also create long runs while freeing up your spare hand. MIG welding is a great option for beginners that are just getting started.
On the other hand, the MIG weld vs. TIG weld needs to be examined if you are working with thin materials. In this case, TIG welding is going to be a better option. Plus, MIG vs. TIG welding for beginners shows that this option is ideal for a welder with experience since there can be a learning curve involved. TIG welding is also preferable when working with non-ferrous metals. Additionally, TIG welding is recommended for bench work, short runs, and delicate materials.
Speed
Let’s look at the speed between the TIG weld vs. MIG weld. Overall, MIG welders are faster, but the TIG weld is clean and better looking. To achieve this level of quality, you can’t accomplish anything quickly. The TIG welder requires a slower process to ensure the weld puddle is adequate.
Additionally, the TIG welder torch can get hot when you attempt to do long runs. To fix this, you would need to invest in a water-cooled versus an air-cooled torch. If you are trying to get the weld done fast and you don’t need professional quality, the MIG welder will get you back to life sooner.
Gas
Shielding gas is important to evaluate between MIG vs. TIG vs. stick welding. These gases keep the reactive gases in the air from contaminating the weld puddle. If you don’t use the right type of gas, there will be impurities.
TIG welding requires argon gas in pure forms. You don't want any oxygen or carbon dioxide because the tungsten electrode is very sensitive. However, MIG welding uses a blend of argon with carbon dioxide, nitrogen, or helium. The additional gas helps to stabilize the welding arc for good penetration. You need to choose the right gas based on what material you are working with.
Aesthetics
Is it best to use a MIG welder vs. TIG vs. stick when you want the best appearance? The TIG welder is going to create the most professional beads, with minimal spatter and no need to polish. These are the best when you aren’t painting or coating the material.
However, MIG welds aren’t unsightly. If you have some experience, you can lay great beads with a high-quality MIG welder. If you plan to coat stainless steel, this won’t even be a big concern.
For Materials
Should you perform MIG vs. TIG welding for stainless steel? Stainless steel doesn’t retain heat the same way as milder steel. For this reason, it can warp easily. That’s why you want to use a TIG welder for better heat control. You also want to have a lot of experience.
What’s more appropriate, MIG vs. TIG welding for aluminum? Again, TIG welding is usually best, but not because of the heat. Aluminum conducts heat well, but oxide forms when it is exposed to air, causing trouble with the arc. TIG welding provides an alternating current that cleans off the oxide quickly.
Difficulty to Learn/Ease Of Use
A big TIG vs. MIG welding difference is the level of expertise that’s needed. TIG welding is more difficult to perform because you must move the torch with your dominant hand and feed the rod with your other. You will also use a foot pedal to adjust amperage along the way. It can take a lot of skill to master all of these movements at once.
MIG welding is much easier to learn, which is why it’s often recommended for beginners. You only need to use one hand, giving you time to get some of the movement down before moving up to a TIG welder.
Cost
What is going to cost more - MIG welding vs. TIG? TIG welding involves a lower deposition rate and slower nature, making the cost higher per foot of welding bead. The machinery is also more expensive. However, you will need to purchase equipment more frequently for your MIG welder. While the machinery isn't much cheaper, the consistent cost of supplies can become overwhelming.
In the grand scheme of things, you won’t notice a substantial difference between the cost of the two, especially because you can find machines at any price point.
MIG Welding For Mechanics (Overview + Pros & Cons)
As you decide between MIG welding vs. TIG welding, let's start with the more popular option. Metal inert gas welding, or MIG welding, is one of the most popular forms for the everyday enthusiast. It can also be called gas metal arc welding or GMAW. Either way, a semi-automatic or automatic arc is required to perform the weld. The shielding gas and consumable wire electrode are fed through the torch or welding gun.
The wire electrode acts as the filler material for the weld, so the composition and diameter vary. You will choose what's best based on the metal type you are working with, the configuration of the join, and the material thickness. Additionally, the wire feed speed must be adjusted to ensure the proper amount of weld material for the joint.
The shielding gas is typically 75% argon combined with 25% carbon dioxide. With this blend, you achieve great weld penetration without too much porosity.
As a mechanic, you may need to MIG weld when you have cracks or rust to repair on a car. It’s also a helpful procedure if you have a cracked muffler or damaged oil pan.
Advantages
Drawbacks
Mechanical TIG Welding (Overview + Pros & Cons)
Let’s examine the other option between the MIG welder vs. TIG. Tungsten inert gas welding or TIG welding is also known as gas tungsten arc welding. This process requires an arc, just like MIG welding, but it is produced by a non-consumable electrode with a consumable filler material instead.
You will feed the rod of material manually into the puddle with your spare hand while the tungsten electrode is responsible for making the arc. The size and composition of the filler rod varies based on what type of weld you need. With the TIG shielding gas, you are typically looking at 100% argon instead of a blend. If there was carbon dioxide involved, it would only promote tungsten oxide formation that would wear down the electrode. It could also contaminate the weld.
The TIG welder also has a foot pedal that allows you to change the amperage during the welding process. With this feature, you can adjust the heat that’s needed, giving you more control over the weld you create.
Mechanics also use TIG welding for the same type of work. However, it requires a lot more expertise to get a high-quality weld. Therefore, it's not the best option for beginners.
Advantages
Drawbacks
Common MIG & TIG Welding Questions
Can you MIG weld inside?
MIG welding is highly affected by external contaminants. For this reason, MIG welding should only be performed indoors, thereby ensuring the integrity of the bead. Flux-cored welding is best for outdoor assignments.
How does Arc welding differ from MIG & TIG?
Looking at the arc welder vs. MIG vs. TIG, we see this technique requires an electric arc created from intense heat, either produced manually or mechanically. It's not the easiest technique to learn, so not something for beginners.
Can you TIG weld without gas?
You should never use your TIG welder without shielding gas. It is needed to protect the tungsten electrode. Plus, the shielding gas protects the weld pool from contamination from oxygen.
Is cold welding the same as TIG welding?
No. Cold welding requires no heat. It relies on resistance that’s created when the electric current moves through two metal alloys. On the other hand, heat is involved with TIG welding.
Conclusion
What is TIG welding vs. MIG welding, and which one should mechanics use? While both of these welding techniques can supply a great weld, the decision comes down to your experience level and the materials you are working with.