How would you troubleshoot poor fusion at the base metal when TIG welding a stainless steel butt joint?

• A. Replace welding machine
• B. Check shielding gas pressure only
• C. Increase travel speed
• D. Inspect joint fit-up and root gap, verify cleanliness and oxide removal, check shielding gas coverage, adjust heat input and travel speed, and confirm compatible filler metal.

Answer: (D)