Answer
Return to 180 on rough spots, then finish with 220 after the surface feels even.
Why it happens
The roughness was not fully removed at the earlier grit or the grain was raised.
Recommended grit
Return to 180 if roughness remains, then finish with 220.
Wet or dry
Dry.
Success check
The surface feels even with no rough islands.
What to do
- Identify whether roughness is across the whole surface or only spots.
- Return to 180 on rough areas.
- Sand evenly, then clean.
- Use 220 for final prep.
Avoid: Do not polish rough wood with 320 before it is leveled.