Quick Answer

When you need to remove 2-5 mm of concrete, start at a coarser grit than you think—usually 16/20 or 30/46—and step through 60, 120, 200, 400 before resin. Skipping a grit wastes time because the next finer disc cannot erase the previous scratch.

Standard Sequences

Job	Metal-bond sequence	Resin sequence
Heavy stock removal (2-5 mm)	16 → 30 → 60 → 120 → 200	50 → 100 → 200 → 400 → 800 → 1500 → 3000
Light grinding (0.5-1 mm)	30 → 60 → 120 → 200	50 → 100 → 200 → 400
Maintenance / coating prep	60 → 120	Skip or 100 → 200

Our R3 round-segment shoes is stocked in 30/46 and 60 grit; ask for other grits.

Why You Cannot Skip Grits

Each grit cuts a specific depth of scratch. If you jump from 30 to 120, the 120 disc cannot erase the 30 scratch pattern—you will see it through every later step, even under polish.

How to Speed Up Heavy Removal

• Use taller segments (10-15 mm).
• Run two passes in opposite directions.
• Do not force the machine; let the diamonds cut.
• Keep the plate flat. Tilting creates gouges that take extra grits to fix.

Browse concrete grinding discs category for the full metal-bond range.

Frequently Asked Questions

Q: Can I start at 16 grit on a residential floor?

Only if you need to remove significant concrete. On a normal floor, 30 is aggressive enough.

Q: How do I know when to move to the next grit?

When the previous scratch pattern is fully gone. Walk the floor in raking light.

Q: Do I need resin pads after metal bond?

For polished concrete, yes. For epoxy prep, metal bond 120 is the finish line.

Conclusion

Heavy grinding rewards a strict grit ladder. Start coarse, step every grit, and do not skip. contact JOY TECH for a full set sized to your project area.