Answer
For 3D prints, use 220 or 320 for layer lines, then 400, 600, 800, and finer.
Why it happens
Layer lines and plastic material need careful progression to avoid gouges or heat marks.
Recommended grit
Use 220 or 320 for heavier layer lines, then 400, 600, 800, and finer.
Wet or dry
Dry for early shaping; wet for fine stages.
Success check
Layer lines are reduced and the surface pattern is even.
What to do
- Remove loose strings or burrs first.
- Start with 220 or 320 only if layer lines need leveling.
- Use light pressure.
- Refine through 400, 600, and 800 or finer.
Avoid: Do not overheat or gouge the plastic.