Tungsten Inert Gas (TIG) welding offers unsurpassed control, with the ability to weld virtually any metal. If your goal is to learn the fine art of TIG, also known as gas tungsten arc welding (GTAW), you might be wondering if you can teach yourself how to weld this way.
Can you really teach yourself TIG welding? It is not recommended to teach yourself TIG welding, the learning curve for TIG is much steeper than other types of welding, and it takes time to develop a proficiency with the process.
While learning how to weld is a very extensive process, understanding a few basic concepts may give you a better idea of what you need to do. In this article, we’re going to go over some of those concepts so that you can have a good grasp of what you might be going into when trying to learn how to weld.
Basics of Welding
All welding processes are essentially methods for applying heat to metals being combined in a controlled manner. TIG welding does this with a tightly focused electric arc, shielded from the atmosphere with an inert gas. With the TIG process, you have the potential to make a weld with a prized “stack-of-dimes” or rope look.
In the field, TIG welding is applied to a variety of different tasks. From welding sheet metals for the food industry to working on race car frames. TIG welding isn’t just for companies, however. Anyone can use TIG to complete at-home welding projects or creating metal art pieces.
If you want to learn TIG welding on your own, however, it is recommended that you get some type of proper training to help you learn the basics and to avoid unnecessary mistakes.
Learning TIG Welding
Any sound structure needs a solid foundation, and it’s no different when learning how to TIG weld. Learning, training and practicing are keys to becoming a proficient welder.
If you teach yourself, no one is there to correct your bad habits or stop you from doing something wrong. Also, you won’t have the access to hands-on training and advisement or the ability to learn tricks of the trade.
What You Will Learn
It takes time, skill and coordination to TIG weld correctly. By getting proper instruction, here are some of the things you will learn:
- Cleanliness – In TIG welding, cleanliness is of the utmost importance. Your surface area needs to be free from dust and debris and, most importantly, you need to keep your tungsten free from contamination. When preparing the tungsten, oils from your finger or residue from your glove can easily damage the weld.
- Setting the TIG machine polarity – When preparing to TIG weld, you need to adjust the polarity to either AC (for aluminum) or DC (for most any other metal). When we talk about polarity in welding, we are talking about the flow of energy. Welding can either have a positive or negative polarity. Polarity plays a big part in the overall quality of a weld.
- Setting the machine heat (amps) – Different machines will have different dial setting such as fine-tuning controls or basic amps. A good rule of thumb when setting the heat is that you’ll need a minimum of one amp for every 1/1,000 inch of metal thickness (45 amps for 18-gauge steel, for example). Most decent TIG machines allow you to vary the heat as you weld, either with a foot pedal or control on the torch body.
- Using the right shielding gas at the right flow – Using the proper shielding gas (mainly argon) is essential to a good weld. The release of the shielding gas can happen at different speeds. These speeds are measured in CFH or cubic feet per hour. If you aren’t using enough gas, it won’t be adequately protecting the weld pool from the atmosphere. Air contains nitrogen, oxygen, and carbon dioxide, which will all contaminate the weld. Aluminum, for example, requires around 17 CFH to weld correctly.
- Holding the rod at the correct angle and feeding it correctly – The angle of the torch is a very important part of the process. It makes sure that the amount of burn-in is correct and provides enough shielding gas to the weld pool. If the torch is pointed too directly at the base material, it can result in unsightly burning and brittleness.
- Using the right size of electrode – Tungsten electrodes come in a few different sizes, each tailored to a specific job. It’s important to know which one is right for your job. The wrong electrode can negatively affect the appearance and strength of a weld. Using an electrode that is incongruent with the job can even be dangerous for the welder.
What You Need for TIG Welding
One of the reasons that it is so challenging to learn TIG welding is because there are a lot of different skills to master. You not only have to learn how to properly hold the torch and move it consistently, but the timing for adding the rod and dabbing it on in a clean manner need to be mastered as well.
Here’s a closer look at some of the essential details and tools needed for TIG welding:
TIG welding uses a variety of equipment types. If you are just starting out, an inexpensive, entry-level machine should suit you well. The least-expensive machines are DC only, which is fine for most metals but will not work for aluminum or magnesium. Most mid- to upper-range machines will have both DC and AC output.
Another feature you might want to look at is the frequency of the circuit. Circuits with high frequencies will allow the arc to form without contact between the weld and the electrode.
Without this high-frequency circuit, the weld may need to scrape the electrode against the metal first to establish the arc—a technique referred to as a scratch start. Scratch starting can easily contaminate the electrode, however, causing significant issues with your weld.
The piece of equipment that you are going to have your hands on for the most part is the torch. The filled rod is added with the other. Air-cooled torches are simpler to use and adequate for most jobs. Water-cooled torches are smaller and better suited for high-amperage welding.
To adequately use a torch, you’re going to need to hold it at a 15-degree angle towards the weld. This is going to give you more control, which makes the weld look more attractive overall.
The electrode used is sanded down, to where it almost comes to a point. The sanding should be in the direction of that point and it should come out looking almost like a pen in shape. The point is going to help with the precision of the weld. This is especially important when dealing with detailed jobs or thin materials.
The collet, the device that holds the electrode in place, should stick out 1/8 to 3/16 of an inch. A ceramic cup (available in a variety of sizes) surrounds the electrode and directs the flow of the inert shielding gas.
As you could probably guess, the electrode is going to need to be a certain distance away from the weld. For sheet metal, anything over 1/8 of an inch thick can make the puddle so large that it falls through, leaving a hole. It’s wise to keep a number of sharpened electrodes close by when welding to minimize your trips to the sander to re-point them.
Trubleshooting Your TIG Welds
Once you learn the basics of TIG welding, you will need to understand some of the complications that can arise with the process. Below are a few of the signs you might see in your welds.
- Brown or Black Smudge – A brown smudge on steel or a black smudge on aluminum is a sign of a contaminated electrode. These smudges are going to make your weld much less attractive, so try to avoid this.
- Porosity – This indicates insufficient shielding gas coverage or some sort of contamination, possibly from any leftover paint or grease that wasn’t cleaned from the metal. This is one of the most common problems to come by because it is so easy to forget to clean your materials. That is why it is crucial to remember this step.
- Lack of Bonding – Insufficient heat can cause the weld to not fully bond with the metal. This is very clearly a problem, making your weld basically useless. Understanding the heat levels and polarity needed for your weld job is going to help you miss mistakes like this in the longrun.
A good weld should show evidence of the penetration on the back while being a little bit fuller at the top where the excess metal cooled.
As you have read, there is a lot to learn about proper TIG welding, and you may not ever get it right without someone helping you.
Whether it’s through a community or technical school, a private tutor or through online courses, learning how to TIG weld with the help of a trained professional will make all the difference in your welds.