Answer
For concrete countertops, wet sand through 400, 600, 800, 1000, then 1500 or 2000 before sealing or polishing.
Why it happens
Concrete needs a gradual grit progression before sealing or polishing steps.
Recommended grit
Use 400, 600, 800, 1000, then 1500 or 2000 for a smoother finish.
Wet or dry
Wet.
Success check
The surface has a consistent fine finish with no obvious scratch lines.
What to do
- Clean loose dust and debris.
- Wet sand with 400 or 600 to refine the surface.
- Progress through 800, 1000, then 1500 or 2000.
- Clean slurry before sealing or polishing.
Avoid: Do not skip grits when trying to remove visible scratches.