Welding is a process widely used for industrial applications. Professional welders have plenty of work in the construction and manufacturing industries. DIY enthusiasts often weld for repairs and other home projects.
However, unlike DIY enthusiasts, professional welders master several welding methods. Commonly, different welding methods are grouped into four categories:
- Gas Metal Arc Welding or GMAW, in which the welder uses a wire as the electrode;
- Gas Tungsten Arc Welding or GTAW, in which the welder uses a tungsten electrode;
- Shielded Metal Arc Welding or SMAW, in which the welder uses a consumable metal stick as the electrode. This is by far the most popular welding method and the preferred by DIY hobbyists;
- Flux Cored Arc Welding or FCAW, in which a wire with a flux core is used as the electrode.
Of the above welding methods, GTAW is the most common for non-ferrous metals. This is also one of the most difficult welding methods to learn and master. Common metals, for which this welding technique is quite effective, include aluminum and copper.
This is the reason why some industries in which these materials are used demand GTAW professionals constantly. One of these industries is aerospace manufacturing.
How GTAW Works
For this technique, also known as Tungsten Inert Gas (TIG) welding, the welder uses a tungsten electrode. However, unlike other methods, the electrode is not consumed while welding.
An inert gas, commonly argon, is used to shield the welding area. The welder must have very precise control of the electrode. This precision is needed since just a small distance separates the arc and the metal being welded. The result, however, is a weld of superior quality.
Both resistance and finish of the weld are of unmatched quality with this method. This technique is suitable for thin metal.
Welding aluminum with this technique is difficult. Not every welder has the skills to do it. There are many details that the welder must take into account for a successful weld. Failing to observe all those details will inevitably result in faulty and/or poor-quality welds.
Hence, this article aims to give the professional welder 8 tips to ensure the welding job with aluminum is done properly. These tips are the result of many years of experience from professional welders. Hence, rest assured you are getting sound advice.
Tips to Weld Aluminum Using GTAW
If you already know the basics of GTAW and want to become an expert at welding aluminum, learn these tips. However, remember that mastering a welding technique takes a lot of practice.
Hence, apply these tips whenever you have the opportunity to weld aluminum. Practice makes the master. With these tips and a lot of perseverance, you’ll be a proficient aluminum GTAW welder in no time.
Tip 1. Make Sure You Weld on a Clean Surface
Many welders that are familiar with SMAW know that they don’t need to clean the weld area. Stick welding, as SMAW is also known, will work on rusted or painted metal. But this is not the case with GTAW. This is particularly true with aluminum.
Before you even begin to set up your welding equipment, clean the metal surface thoroughly. Even though not easily seen, aluminum gets rusted when it is exposed to the weather elements for a long time.
Failing to clean the surface properly will result in a faulty weld. Moreover, you’ll have a lot of spatter and sparkle when you weld.
Tip 2. Set the Welding Machine Properly
This is something that you will have to learn very well. Setting the welding machines is of paramount importance for GTAW. This is particularly true for welding aluminum.
Not setting the machine properly will result in an unstable arc. Hence, read the manual of your welding machine and abide by the recommendations to weld aluminum.
Tip 3. Amperage is Critical
Unlike other metals like steel, aluminum is a very good conductor of electricity. Hence, you have to control the amperage properly to prevent heat buildup.
You control the amperage with a pedal. It will take some practice to control the electrical current while you weld. Don’t give up.
Tip 4. The Arc Length Plays an Important Role
Welders that are used to welding steel and other ferrous materials don’t care much about the arc length. In most cases, the arc length is not so critical when welding steel. But with aluminum, the arc length plays a very important role.
Use an arc that is too short, and the metal won’t heat up properly. Contrarily, using an arc that is too long will create a lot of spatter. Hence, you will have to learn to control the arc length to always get optimal results.
Tip 5. Keep the Electrode Clean
We already mentioned the importance of cleaning the metal surface that will be welded. Well, no less important is keeping the tungsten electrode clean. This is particularly critical when you weld aluminum. Dirt will result in a sooty weld.
Again, this may not be so important when you weld steel. Welding aluminum, on the other hand, requires that both the metal surface and the electrode are free of dirt.
Tip 6. Don’t Weld at an Obtuse Angle
You cannot use excessive tilting with GTAW; otherwise, you will end up melting the tip of the electrode. This can happen with any metal, but aluminum can be particularly disastrous.
Tip 7. Use the Proper Electrode
Not only do you need a clean tungsten electrode but also the right one. Some machines need an electrode made of pure tungsten. However, other machines such as TIG inverters need an electrode made of tungsten alloy.
Besides a faulty weld, the use of the wrong electrode can result in permanent damage to your welding machine.
Tip 8. Size Matters
If you have some experience welding steel with this technique, the chances are that you use a standard electrode of 3/32” in diameter. This electrode size will cover most scenarios when you weld steel.
For aluminum, however, the size of the electrode matters. Depending on the thickness of the metal, you may need a thinner or thicker electrode. So, besides the standard 3/32”, always carry with you 1/16” and 1/8” electrodes.
Conclusion
This article has given you tips from professional welders to weld aluminum using GTAW/TIG. Use these tips whenever you weld aluminum.
Most importantly, practice all the time. These tips won’t do anything to improve your welding technique if you don’t practice.
