Aluminium Welding Print
Written by Greg Holster   

Aluminium Welding

Part 4: Basics of aluminium welding, the fourth in a series of how to weld

Aluminium alloys are used in so many different applications in our modern world, from motorbike frames and boats, big and small, to superyachts. The list is endless. So when it comes to building, manufacturing and repairs, welding is often the best solution. Most aluminium alloys are weldable, but it is important to understand the special aspects and quirks of working and welding aluminium and the welding technique.

Easily the most overlooked problem in welding aluminium is not having a clean welding preparation. So first up, cleanliness is of the utmost importance. When faced with repairs in the shed or workshop, you will find aluminium that is old, dirty, or with an oxidised surface will need to be cleaned.

TIG welding uses a non-consumable tungsten electrode surrounded by a ceramic shield which controls the flow of the protecting argon gas. Argon gas shields the molten metal from the oxygen and nitrogen in the atmosphere which would otherwise oxidise the metal and rod. The argon also acts as a carrier for the current which is the heat source.

The electrode tip in the TIG torch for steel or stainless steel is very pointed and made of thoriated tungsten. For aluminium welding, the TIG torch tungsten electrode should be blunt, the corners ground off and is made of zirconiated tungsten. The tungsten electrode has a white tip for aluminium and a red tip for steel.

Read more in the latest issue of The Shed