How to Grind Concrete Floors to Expose the Aggregate
- 1). Open all windows and exterior doors. Place box fans in the windows and doors on the downwind side of the room with a concrete floor.
- 2). Equip a hand-held angle grinder with a 16-grit concrete-grinding pad. Use a grinding pad designed for the angle grinder -- a 4-inch grinding pad fits a 4-inch grinder, an 8-inch grinding pad fits an 8-inch grinder, and so on.
- 3). Put on safety glasses, ear protection, leather work gloves and a dust mask.
- 4). Turn on the angle grinder and remove an 8-inch-wide strip of the top layer of concrete from the floor's corners and along each wall. The angle grinder polishes hard to reach areas of the floor.
- 5). Place a 16-grit concrete-grinding pad on a floor grinding machine, using the grinding machine's instructions.
- 6). Grind the surface of floor with the floor grinding machine, starting at one end of the room and work across the room in circular motions. Blend the body of the floor into the polished 8-inch-wide edge. Keep the grinding machine moving across the floor at all times.
- 7). Clean the concrete floor with a broom and dustpan.
- 8). Switch the grinding pads on the hand-held grinder and the floor grinding machine to 32-grit grinding pads.
- 9). Grind the concrete floor's edges and corners, using the hand-held angle grinder. Remove the top layer of the concrete floor's body with the floor grinding machine, blending the floor's body into the edges.
- 10
Grind the concrete floor with the hand-held angle grinder and floor grinding machine until it has the desired finish, using the same method used on the first and second pass. The third pass should use at least a 64-grit pass and the forth pass should use at least a 128-grit pad. Continue to double the grinding pad's grit with each pass.
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