Quick Answer

A glass-like finish on concrete requires the complete grind-and-polish sequence with a planetary grinder: coarse metal segments (30-60 grit), transitional pads (80-200), a densifier after 200-400 grit, resin polishing through 800, 1500, and 3000 grit, then final burnishing. The planetary motion removes the directional scratches that single-disc machines leave, which is exactly why it produces a cleaner, mirror-like gloss.

Why a Planetary Grinder Is Best for Glass Finishes

• No swirl marks — the counter-rotating planetary heads cancel directional scratch patterns.
• Even pressure — the machine sits flat, so the whole disc path polishes evenly.
• Efficient coverage — wide tooling area shortens the total grit cycle on big floors.
• Consistent overlaps — passes blend into each other, which matters at high grits.

The Grit Sequence That Delivers Glass

Step	Tooling	Grit
1. Open the surface	Metal-bond trapezoid discs	30-60
2. Remove coarse scratches	Ceramic / copper transitional pads	80-200
3. Densify	Lithium densifier	after 200-400
4. Refine	Diamond resin pads	400-800
5. Polish	High-grit resin pads	1500-3000
6. Burnish	White pad / burnishing pad	final

Tips That Make or Break a Glass Finish

• Clean between every grit step — stray abrasive particles scratch the floor at the next step.
• Dry-polish the final grits — water can dilute the resin action and leave a hazy matte; a dry polishing sponge pad helps finish edges clean.
• Use a white resin pad like diamond white resin floor polishing pads at the top grit for a bright, clear reflectivity.
• Overlap passes by 50% — gaps show as matte bands under raking light.
• Burnish in crosshatch directions — final passes at 90° to the previous direction even out the gloss.

When Glass Is Not the Right Goal

A full 3000-grit glass finish is more slippery under wet conditions and shows scratches more easily in high-traffic retail areas. Many showrooms prefer a satin 800-1500 finish that looks premium but hides wear. Reserve true glass for lobbies, display floors, and spaces with low, controlled traffic.

Frequently Asked Questions

Q: Do I need 3000 grit for a glass finish?

A: Yes, for a true mirror look. Stopping at 1500 gives a high satin; 3000 plus burnishing produces the reflective glass effect.

Q: Can a single-disc machine get a glass finish?

A: It can, but swirl marks are harder to avoid. A planetary grinder cancels directional scratches and is the reliable route to a mirror finish.

Q: Why does my floor look hazy after 3000 grit?

A: Usually a skipped grit step, polishing wet at the top grits, or not cleaning between steps. Go back one grit, clean, and re-run the sequence.

Q: How much does a glass finish cost more than a standard polish?

A>Expect 20-40% more labour and material cost versus a standard 800-grit satin polish, mainly from the extra grit steps and burnishing.

Conclusion

A glass finish on concrete is achievable with a planetary grinder when you respect the sequence: full grit steps, densify mid-sequence, clean between passes, and finish with white resin pads and burnishing. Match the target gloss to the traffic — glass looks stunning in lobbies, satin serves busy retail floors better.