Soot
When welding aluminum with a “pull” technique (torch angled backward), soot often forms on the weld surface. Aluminum quickly develops an oxide layer, which is not sufficiently broken up with the wrong torch angle. As a result, the shielding gas cannot protect the weld pool effectively. For this reason, aluminum should always be welded with a “push” technique (torch angled forward) to prevent soot and oxidation.
How to avoid it:
- Always use push welding technique for aluminum
- Maintain a steady torch movement and correct welding angle
- Ensure stable gas flow and proper torch positioning
