In the latest installment of Products Finishing's (PF) On the Line, we caught up with Connor Callais, product manager at Hubbard-Hall (Waterbury, Connecticut), to talk about the fundamentals that finishers most often get wrong in parts cleaning and pretreatment, best practices for bath chemistry maintenance and regulatory trends shaping the industry. Callais, a member of PF's 40 Under 40 Class of 2023 and a regular contributor to the PF's Ask the Expert column, draws on his years as a technical application specialist working hands-on with customer lines to explain where finishing operations tend to go wrong — and how closer monitoring and earlier conversations with suppliers can prevent it.