Answer
Between shellac coats, use 400 or 600 very lightly after the coat dries.
Why it happens
Light scuff sanding can remove nibs, but shellac films can be thin and easy to cut through.
Recommended grit
Use 400 or 600 very lightly between coats.
Wet or dry
Dry.
Success check
The surface feels smooth and is ready for the next coat.
What to do
- Let the shellac dry.
- Scuff lightly with 400 or 600.
- Remove dust with a clean cloth.
- Apply the next coat lightly.
Avoid: Do not sand through thin shellac layers.