Aluminum welding is a complex skill and the more you know before taking on a task, the better you are likely to be at it. This handy set of tips about aluminum welding will be particularly useful to all beginners and focuses on skills that might take months to acquire through practice alone.
Heat the Aluminum
Try running a blowtorch over the aluminum before you begin welding. This will minimize the amount of distortion you often find when the heat of a welding torch causes a local hotspot on the aluminum.
The aluminum welding will be completed faster and also be more accurate if you remove the oxide layer from the aluminum first. Do this with a wire brush made of stainless steel and clean the edges of the aluminum with a file.
It’s possible that you could have contamination on the tungsten tip of your welding gun. If this happens, you need to stop working immediately. This is something that can happen quite regularly and whenever it does, you need to resolve the problem before continuing.
Welding aluminum needs to be done quickly. Once you begin you have to keep going otherwise there’s a real danger of burning through the aluminum because it becomes overheated. The welding gun should keep moving along the weld and the practice is very different to welding steel.
You need to be particularly accurate with aluminum welding. You must always try to fit the pieces together tightly before you begin a weld to ensure it’s accurately set and properly cleaned . With aluminum, there’s no possibility of filling the gaps between surfaces in the same way you can manipulate steel.
TIG Versus MIG
Welders agree that TIG welders are the best equipment for aluminum welding. They’re relatively easy to use and do the job quickly. However, the expensive prices associated with TIG welders mean that they’re out of the financial range of most home welders. This is why most people use MIG welders. They are more affordable but, unfortunately, they’re much harder to use. If possible, use a TIG welder for your job. Hiring can be a consideration if it can ultimately proves to be cost-effective.
Your welding gun requires inert gas for aluminum welding. Ideally you should use pure argon but, depending on the equipment you have, you can also use a mix of argon and helium.
The spring tensioner on the wire needs to be tightened so the wire reel doesn’t unravel and the first 3 inches of wire has to be very straight. This stops damage to the liner as the wire is fed through in the welding gun.
Try removing the tip from the welding gun before you feed the wire through although you should never attempt this when the tip is hot. At times the wire can snag in the welding gun. If this happens, try pulling it back onto the reel then run the gun a little as you try to push the wire back through.
Use a brass heat sink for aluminum welding. Clamp it behind the aluminum to be welded. It takes heat out of the weld and allows you to be slower and more accurate. This will ultimately result in a neater weld.