Answer
For trim before painting, clean first, then scuff with 180 or 220. Use folded paper for profiles.
Why it happens
Trim needs cleaning and scuff sanding so primer or paint can bond to the old finish.
Recommended grit
Use 180 or 220 for scuff sanding. Use 320 lightly between cured coats.
Wet or dry
Dry.
Success check
The trim is clean, dull, and evenly scuffed before paint.
What to do
- Clean the trim before sanding.
- Scuff glossy areas with 180 or 220.
- Fold the paper for profiles and grooves.
- Remove dust before primer or paint.
Avoid: Do not paint glossy trim without scuff sanding.