Quick Answer: Move a floor machine across concrete at about 0.3 to 0.6 metres per second with a half-head overlap, and a hand grinder at a similar steady pace in overlapping passes. Speed matters less than consistency: the same feed rate, overlap, and pressure on every pass keeps the floor flat.

Feed Rate: The Number That Matters

Grinding too fast removes less material and leaves a wavy surface; grinding too slow dwells and over-cuts a band. A steady walk-pace feed of roughly 0.3 to 0.6 m/s works for most floor machines, and a hand grinder should move at a matching slow, deliberate rate. The goal is even contact time everywhere, so measure your pace on the first pass and reproduce it on every subsequent pass rather than aiming for a precise number.

Overlap and Direction

Overlap the previous pass by about half the head width on a floor machine, and by about a third of the disc diameter on a hand grinder. Run passes parallel to one another, then turn 90 degrees on the next grit step so any grinding lines cross and cancel. On very uneven slabs, tighten the overlap on the first coarse pass to catch the low spots, then widen it as the floor flattens.

RPM and Disc Pressure

Run the machine at the RPM the tooling was designed for. arrow-segment cup wheel, usually printed on the pad or disc. Too slow makes metal bond rub and glaze; too fast overheats resin pads. On hand grinders, keep the disc speed high and the feed slow, using pressure only to keep the disc flat. A single-row cup wheel cuts fast at full RPM, while finer resin pads need a gentler touch. resin polishing pads and a slower machine speed to avoid burning.

Adjusting for Concrete Condition

Hard, dense concrete needs a slower feed and a coarser bond; soft concrete cuts quickly and can over-remove at a normal pace, so slow down. Surface coatings and glue call for PCD tooling at a steady pace rather than speed. Check the floor with a straightedge every few passes; if the flatness drifts, change the feed or overlap before the whole floor follows.

Is it better to grind fast or slow?

Slow and steady. Speed removes material less efficiently, leaves vibration marks, and makes the job inconsistent. A consistent moderate feed with correct overlap flattens the floor faster in practice.

How do I know if I am going too fast?

If the floor shows bands or the disc skips across high spots instead of cutting, slow down and tighten the overlap. Vibrating passes and loud bouncing are signs of a feed that is too fast for the tooling.

Conclusion

Grind flat concrete at a steady 0.3 to 0.6 m/s feed with consistent overlap, correct RPM, and even pressure. Consistency across every pass is what keeps the floor level, so set the pace once and repeat it on every grit.