A three-head planetary machine covers more area per pass and flattens better than a single head, but only if the passes are planned. Run it like a single-head machine and you get swirls, waves and an uneven gloss that shows under raking light.

Machine behaviour to plan around

Characteristic	Effect on the floor	Response
Counter-rotating heads	Very flat cut, low swirl	Fewer passes, but keep them systematic
Wide footprint	Fast coverage, hard to feel edges	Mark lanes, overlap deliberately
Weight	Aggressive at low speed	Speed up before increasing pressure
Water spread	Dries unevenly at lane edges	Water the lane before the pass

Pass sequence

1. Divide the floor into lanes one machine width plus 100 mm and mark them with chalk.
2. Run the first direction north-south, overlapping 30-40 % between lanes.
3. Run the second direction east-west at the same grit, so every point is crossed twice.
4. Change grit only when the whole area shows the previous scratch pattern uniformly.
5. Repeat the two-direction pattern at every grit; do not shortcut the cross pass at 400 and 800.
6. Finish with a slow single direction pass at the final grit for a uniform direction of polish.

Speed, water and pressure

• Keep a steady travel speed; stopping in one spot with three heads burns a ring fast.
• Water lightly ahead of the machine so the heads always cut wet, never flooded.
• Use machine weight for pressure; leaning on the handle tilts the head and leaves waves.
• Change or clean pads every 300-400 m2; loaded pads polish unevenly and hide defects.

Checking the result

After each grit, stop and look across the floor at a low angle from two directions. Any remaining pattern from the previous grit will be magnified by the next one. Mark problem zones and re-run them at that grit before moving up, not after the polish is finished and the defect is locked in.

Plan the lanes on paper before the machine starts. The sequence is the quality control, and it costs nothing but a chalk line.