Ultimate Guide To GMAW For Successful Aluminum Welding
Aluminum welding techniques have come a long way from a basic welding technic to todays GMAW (Gas-Metal-Arc-Welding). Nowadays, it is one of the most dominating processes among the fabricators across the world.
Mastering welding means to deliver a custom-made aluminum sheet metal fabrication without any flaws. GMAW comes with a set of challenges which hampers a welder/fabricator. To overcome these challenges, learning the basic technics could make a great difference. The following basic guidelines will help you to successfully weld aluminum.
Preparation of Base-Metal
The first step a operator needs to do is to clean the base material. Typically there is aluminum oxide or hydrocarbon on the metal, it should be removed for an effective welding process.
Aluminum oxide on the surface tends to melt at 3700 F, whereas the base material underneath will melt at 1200 F. Hence, leaving any oxide on it can adversely affect the procedure of welding.
Handling of Weld Gun
When it comes to using a welding gun, it becomes necessary to hold it correctly. Pushing it away from the aluminum instead of pulling can help you reduce weld contamination, resulting in better cleaning. Besides the proper use of the welding gun, travel speed is what matters the most in successfully welding two pieces of aluminum sheet metal together. It needs to be done with an approach of ‘hot and quick.’ Should your travel speed be to low, there is a high chance to burnthrough, especially when welding thin material.
- Apart from handling a welding gun, there are several other dos and don’ts which a welder should know.
- For aluminum welding, the specific gun liner should be used.
- Restraining both the ends of the liner would eradicate the gap between it and the gas diffuser of the gun.
- To restrict wire-feeding problems, using a contact tip which is 0.015 inch (approx.) larger than the diameter of filler metal can work wonders.
- If a welding current exceeds 200 A, using a water-cooled gun can help you to minimize heat buildup which will reduce the difficulty of wire-feeding.
How to Select Correct Welding Wire?
Choosing an aluminum wire as a filler that has the same temperature as the base material can be a great idea. The similar melting range to the metal can make it easier to weld it. However, getting the accessibility of welding entirely depends upon how large diameter is.
Which Power-Source to Prefer?
First of all, a welder needs to make a choice which method of transfer he will be using, i.e. whether to opt for spray-arc or pulse. If you go for the first one, using constant current (CC) and constant voltage (CV) machines can help you attain optimum results. On the contrary, pulse transfer can be performed on inverter power supply.
Following these basic guidelines will give you a good start in aluminum welding. You can order a custom-made aluminum sheet metal fabricated box with welded corner on our website. We cut it. We bend it. We weld it for you.
