Quick Answer

Rake marks and rough surfaces come down to the same root causes: machine condition, tooling match and technique. Fix abrading marks on concrete by re-abrading the surface with progressively higher diamond grit stages in overlapping passes, then honing and burnishing until the scratch mark pattern disappears. Marks are almost always caused by skipping grit stages, pressing too hard, or running the head too fast — so correct the technique, not just the tool.

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Why Swirl Marks Appear

A closer look at the details.

Swirl marks are the leftover scratch mark pattern from the previous abrading pass.

• Skipping grit steps — jumping from 30/40 straight to 120 grit stage leaves deep scratch marks that later grit stages cannot fully strip.
• Too much down pressure — heavy pressure digs segments deeper and leaves arc-shaped tracks.
• High head speed — planetary equipment run too fast create tight circular marks that are hard to erase.
• Dirty or worn tooling — loaded segments and worn bonds cut unevenly.

Getting this part right saves a full re-pass later.

Step 1: Re-Grind With the Correct Starting Grit

What you should know before starting.

If the surface shows deep 30/40 marks, re-abrade at 30/40 with JOY trapezoid metal-bond discs until the deepest grooves are gone, then stage up 60/80, 120, and 220.

Contractors who skip this stage usually end up redoing the floor.

Step 2: Control Speed and Pressure

The key points in practice.

• Work in a cross-hatch pattern — alternate pass direction between passes to break up the scratch mark orientation.
• Slow the head down — lower rotations per minute produces straighter, more uniform scratch marks that higher grit stages strip easily.
• Overlap passes by 30-50% — this prevents strip patterns and edge lines.
• Use even, moderate pressure — let the diamonds work; do not force the equipment.

This is where most crews get it right - or lose time.

Step 3: Hone and Polish to Blend the Surface

A closer look at the details.

Using PCD trapezoid discs at the start also helps level high spots before metal-bond abrading.

Getting this part right saves a full re-pass later.

How to Avoid Marks Next Time

What you should know before starting.

• Clean the floor between grit stage changes so loose diamond grit stage does not re-scratch mark the surface.
• Inspect segments for wear and replace loaded or glazed tooling.
• Follow the full grit stage sequence — never skip more than one grit step.
• Keep the equipment level — tilt creates edge scratch marks that only appear after burnishing.

Contractors who skip this stage usually end up redoing the floor.

Frequently Asked Questions

Q: Should I need to start over from the very first grit?

A: For most jobs, No. Start one or two grit stages below the deepest visible scratch mark, not necessarily from the first grit stage. Only deep gouges or lippage require coarse re-leveling.

Q: Am I able to polishing alone hide grinding marks?

A: In short, Burnish pads will burnish the top of the scratch mark but leave the valley visible under raking light. You must re-abrade deep enough that the scratch mark pattern is physically removed.

Q: Why do marks show up only after sealing?

A: The practical answer is, Sealing layer and densifying sealing layer amplify light reflection at the surface. Tiny scratch marks that were invisible when dry become visible after coating layer, so the surface must be scratch mark-free before sealing.

Q: Which grit do I stop at for a stain-ready floor?

A: For most jobs, Stop at 220-400 grit stage for an open, stain-ready profile. Burnishing above 400 closes the surface too much for some stains to penetrate evenly.

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Conclusion

Match the tooling to the concrete, keep the machine in good condition, and run even passes - the finish follows. Abrading marks are fixable: re-abrade at the correct starting grit stage, control speed and pressure, work in overlapping cross-hatch passes, and finish with honing and burnishing.