Longtime friend, expert fabricator, and instructor Mark Prosser returns to the podcast to demystify the intimidating world of aluminum TIG welding. Mark breaks down the physics of aluminum, explaining how to manage high-maintenance oxide layers, why modern AC polarity does the heavy lifting, and how to master fast travel speeds. He and the guys also debate the merits of table heat sinks, analyze torch angles, and discuss why old-school pure green tungsten belongs in the trash compared to modern Trimix.