Quick Answer

Smooth a concrete countertop by grinding out trowel marks with coarse metal (50–100), then polishing with resin pads through 400 → 800 → 1500 on a variable-speed grinder with a small pad holder. Work the edges with a hand polisher and finish with a food-safe sealer.

Key Features of Countertop Finishing

• Trowel marks: deep ridges need grinding, not sanding, to remove.
• Small format pads: 3–5 inch pads fit grinder edges and tight corners.
• Wet or dry: wet keeps the dust down; dry needs a vacuum and mask.
• Sealing: countertops must be sealed for food contact and stain resistance.

How to Choose the Pad Size

Area	Pad Size	Tool
Large surface	5 inch	Variable-speed grinder
Edges and radius	3 inch	Hand polisher / pad holder
Tight corners	Hand pads	By hand

How to Use It

• Grind trowel marks flat with coarse metal before any resin step.
• Step through triangle resin floor polishing pads or small round pads from 100 to 1500.
• Keep the grinder moving in overlapping passes to avoid dwell marks.
• Clean, let dry, then apply 2–3 coats of food-safe sealer.

Frequently Asked Questions

Q: What grit removes trowel marks?

A: Start at 50–100 metal to grind the ridges flat, then refine with 100–400 resin.

Q: Do countertops need 3000 grit?

A: Not usually — 800–1500 plus a good sealer gives the smooth satin-to-soft-gloss finish most people want.

Q: Can I polish a countertop with a floor polisher?

A: No — use a variable-speed angle grinder with small pads. Floor machines are too large and too fast for counters.

Conclusion

Grind the trowel marks out, step up through resin pads, and seal for protection. Use triangle resin pads for edge work and a small round set for the face.