If you have a broken piece of cast aluminium outdoor furniture, you may be tempted to throw it away. Cast aluminium is notoriously difficult to weld. Unlike other metals, aluminium does not turn red as it heats, so it's hard to monitor the temperature as you're welding. However, if you have the right tools, it can be done. Alumaloy welding rods work well with cast aluminium. All you need to do the job is the rods and a handheld propane torch.
Thoroughly clean the area you want to weld. It must be totally free of oil or any other dirt.
Preheat the Alumaloy rod using the flame of the handheld propane torch.
As the Alumaloy starts to melt, press the rod into the surface of the aluminium.
Continue to heat the aluminium while dipping the rod in and out of the molten puddle until you have built up the desired amount of Alumaloy.
Let the metal cool completely before touching.
Alumaloy also manufactures welding rods for cast iron and stainless steel.
Protect your eyes with a good pair of welding goggles or a welding helmet.