Answer
For painted metal fence prep, use 120 or 180 on rust and loose edges, then 220 or 320 before primer.
Why it happens
Loose paint, rust, and glossy old coating need different sanding stages before repainting.
Recommended grit
Use 120 or 180 on rust and loose paint edges, then 220 or 320 before primer.
Wet or dry
Dry.
Success check
The fence is clean, dull, and free of loose edges.
What to do
- Remove loose paint and rust first.
- Use 120 or 180 on rough edges and rust spots.
- Refine with 220 or 320.
- Clean dust before primer or paint.
Avoid: Do not paint over loose rust or glossy old coating.