Learn the Tips & Techniques You Need for Learning to Weld Aluminum
You are probably no stranger to the look of a quality aluminum weld. Skilled welders around the world use aluminum welding to great effect in the automotive, aerospace, and construction industries. You may have heard that if you learn to weld aluminum blindly, you may face significant challenges. But what does it take to weld aluminum? Should you use one welder over another? What does the entire aluminum welding process involve? In this article, we at Weldpro will cover the aluminum welding techniques, technologies, and basic mechanical requirements needed to achieve a high quality aluminum weld using the GTAW (Gas Tungsten Arc Welding) or TIG (Tungsten Inert Gas) processes. Learning to weld aluminum-based materials can be a challenge at first – many aspects of aluminum welding can be confusing to the uninitiated. We hope this beginner’s welding guide will help you overcome some of the confusion and doubts.
Learning to Weld Aluminum: AC vs. DC
Using the right equipment for aluminum welding is vital. To achieve a proper weld on aluminum, you must have an AC TIG welding machine such as the Perfect Power
TIG 200 AC DC TIG Welder.AC refers to what is known as “alternating current” and is in direct contrast to direct current or “DC”. AC power is more suitable for aluminum welding equipment than DC power because the positive half of the AC power has a cleaning effect, while the negative half has a penetrating effect. When learning to weld aluminum, the cleaning and penetrating abilities of AC TIG welding machines are the best way to ensure a gorgeous weld.
THE TOP BENEFIT OF AC WELDING ALUMINUM
When learning to weld aluminum, it’s critical to be aware that aluminum requires comparatively higher temperatures to get a quality weld. When looking at TIG welding for beginners, you’ll find that these machines are more commonly used in the aluminum welding process due to their simplicity when compared to MIG welders. Because AC welding is the best power supply for TIG welders, most aluminum products are manufactured using AC welding.
AC PROVIDES BALANCE CONTROL IN TIG ALUMINUM WELDING EQUIPMENT
Prior to the 1970s, the negative and positive half cycle of alternating current was a simple 50/50 approach. Modern aluminum welding equipment now uses what is known as balance control for a more streamlined approach to create the ideal arc for all applications. As a beginner TIG welder working on aluminum, AC-capable machines that feature balance control are essential for making the job easier with better results.
When using AC current, the fluctuation between positive and negative poles occurs very rapidly. The term “alternating current” refers to this reversal in electron flow – something that doesn’t happen with DC. As mentioned, when you use AC aluminum welding equipment, you must control how much balance there is between the polarities. Running a TIG torch on a full DCEP (direct current electrode positive) balance will destroy the tungsten electrode and possibly the torch. DCEP places great heat into the torch and tungsten, while DCEN (direct current electrode negative) current places the heat into the workpiece.
For this reason, we need to be able to balance the polarity heavily on the DCEN side. Typically, this will average out to about 70%. However, there are exceptions to this – such as having oxidized or dirty base material. If you’re working with this type of material, it is essential to have the capability to adjust the balance more to the DCEP side, which allows the cleaning action to happen on the workpiece. The Weldpro TIG 200 has a balance control built-in that works seamlessly, making TIG welding for beginners easier to manage. Balance control can be adjusted anywhere from 30%-70%, depending upon cleaning needs.
Four Top Aluminum Welding Techniques & Tips
Learning to weld aluminum is a complex skill that requires proper knowledge before you take on the task. Keep these aluminum welding techniques in mind to help you focus on the skills you need to master to get the job done right.
1. Preparing the aluminium
When aluminum is cooled in the factory, an oxide layer naturally forms on the exterior. In addition, cleaning oils and contaminants can remain on the surface of aluminum when it is handled. The aluminum welding process always starts with cleaning the surface before you even think about switching on the TIG welding machine. The quality of the weld is significantly different when working on a clean surface. Firstly, it is best to clean the surface with acetone to ensure that it is completely free of oil and any other contaminants. To remove the oxide layer, you will need to use a stainless steel brush. This isn’t difficult, but if you don’t use acetone, you’ll push contaminants deeper into the material and compromise the quality of the weld.
Tig welding tips for beginners always mention the need to preheat the aluminum before you start welding. Essentially, this step in the aluminum welding process will make aluminum easier to work with. Preheating the aluminum with a torch before starting to weld will minimize the distortion that occurs when the heat from the torch creates localized hot spots in the material.
2. Learn how to set up an aluminum tig welder
We’ve already discussed the importance of using AC rather than DC power, but learning to weld aluminum means understanding which electrode to use for a tig welding machine. Tig welding electrodes should always use pure tungsten electrodes, which offer better durability and purity than other types of electrodes. Your electrode should also not be sharpened, as rough alternating current can cause the electrode to fall out into the weld. A common aluminum welding technique used by the masters is to use pure argon as a shielding gas. This gives you the best purity and performance of the weld when welding aluminum.
3. Learn to work fast
A particularly hard step in welding for beginners to master is speed. This is especially important for learning how to weld aluminum, as there’s a real danger of overheating your material if you take stops rather than moving on.
4. Use a radiator
Using a brass or copper heat sink is the best practice when learning to weld aluminum. Since aluminum transmits heat exceptionally well, clamping your project to a heat sink can take the heat out of the weld and allow you to be slower and more accurate. If your weld gets hot enough to start melting, the entire project can begin to shrink and warp. A heat sink is one of the best pieces of aluminum welding equipment to use as a beginner when you’re still trying to work on your speed.
Aluminum Weld Pools Explained for the Beginner TIG Welder
Beginner TIG welders working on aluminum will notice that the weld pool of the material can look very different than when working on mild steel. The weld pool is orange and noticeable on mild steel. However, on aluminum, the weld pool looks more like a small, wet reflective puddle.
Understanding what this puddle should look like is one of the primary principles of welding for beginners to know. It can help you avoid overheating your workpiece while attempting to achieve a weld pool that simply will not happen. Controlling amperage while welding aluminum is very important. You can accomplish this by making good use of the foot pedal. There is often the need to continuously increase and decrease amperage while welding aluminum to achieve a symmetrical weld pool.
For this reason, you must have a TIG welder with a quality foot pedal. The foot control included with the Weldpro TIG 200 package is another reason it can be considered one of the best welding machines for aluminum. It is made to be highly durable, and it consists of high-quality steel and electrical components. It also responds exceptionally well to slight changes and is comfortable to use for long periods.