Aluminum Welding Guide

Most importantly, purchase Hobart products with controlled diameter, stiffness, cast, pitch, surface finish and low surface sliding friction. Secondly, always use a welding system that is designed specifically for welding aluminum like the Miller aluminum welding packages shown on pages 39 and 40 of this brochure. Welding systems like the Miller AlumaFeed have been specially developed and tested to provide high performance and to help eliminate the typical problems experienced when welding aluminum.

Check List:

• Check and tighten electrical connections and grounding.
• Ensure that the base metal is not contaminated with water stains, moisture, heavy oxide, or hydrocarbon containing materials.
• Check that feed rolls, guides and contact tips meet Hobart’s specified profile and surface polish recommendations. They must be free of burrs and machining marks. Use a push-pull wire feeder or spool gun for optimum feedability. See page 40 in this booklet.
• Match the contact tip size to the wire size being used (wire diameter + 10%).
• Caution: steel welding wires are produced to different sizes than aluminum. Using a contact tip designed for steel will cause excessive burn backs with aluminum wire because of inadequate diametrical clearance.
• Contact tips must be recessed in the gas cup 1/8 to 1/4 inch for proper gas cooling of the tip and spatter control. Do not use joggled contact tips.
• Prevent overheating of the gun and contact tip by operating at a reduced duty cycle or switching to a water cooled gun.