A concrete grinder has a variety of uses for the DIYer. You can use the grinder to smooth and polish concrete floors or to roughen up a floor's surface in anticipation of applying a tile or hardwood floor covering. A grinder can remove old paint from a floor's surface, or even out high and low points to create a level slab. All of these uses require essentially the same procedure in using the grinder, varying only in the grinding pad attached to the machine. Because of this, learning to use a concrete grinder properly can extend your remodeling abilities, making existing concrete just one more modifiable surface that you can work with.
Attach the grinding pad securely to the bottom of the grinder. Choose your pad according to the amount of material you wish to remove from the concrete surface. Harder pads can grind away more material in a single pass, but softer polishing pads are necessary to create a gloss finish on the concrete. Use an adjustable wrench to screw the pad into place.
Attach the hose from the grinder to a vacuum for dust collection.
Turn on the vacuum. Move the grinder to the far edge of the concrete surface that you intend to grind. Set the wheels on the grinder for grinding mode.
Turn on the concrete grinder and wait as the motor attains operational speed. You can determine this point because the motor no longer revs up but evens out to a constant pitch. Lower the grinder head to the concrete and move the grinder along the surface using a small circular or side-to-side motion to keep the grinding even. This prevents creating low spots in the surface or swirl marks on the concrete. Push the grinder in a straight line along the edge of the concrete surface, applying light pressure onto the pad to grip the concrete.
Turn off the grinder at the end of the row. Set the wheels on the grinder for transport mode and go back to the beginning of the row. Place the grinder so that it covers the uncovered space next to the already ground area, slightly overlapping the first row by about 2 inches. Turn on the grinder and cover the second row of concrete surface. Continue in this manner until you've covered all of the concrete surface. Turn off the vacuum at the end of the room coverage along with the grinder.
Sweep away any grinding residue missed by the vacuum attachment.