Answer
For rusty metal patio furniture, use 80 or 120 on heavy rust, then 180, 220, or 320 before primer.
Why it happens
Outdoor metal needs rust removal, edge blending, and scuffing before primer or paint.
Recommended grit
Use 80 or 120 for heavy rust, then 180, 220, or 320 before primer.
Wet or dry
Dry.
Success check
The metal is clean, dull, and ready for primer.
What to do
- Remove loose rust and peeling paint.
- Use 80 or 120 on heavy rust spots.
- Refine with 180 or 220.
- Use 320 for smoother visible paint prep.
Avoid: Do not paint over loose rust or flaking paint.