A hand-held grinder could be one of the most versatile items in your tool box. It's a fast solution for smoothing out bumps and other irregularities in both horizontal and vertical concrete surfaces. You can also use it to remove graffiti and worn coatings or paint and to roughen up floor surfaces in preparation for coating application.
With grinding diameters of 5 inches or less, these tools can't replace walk-behind surface preparation machines for profiling large areas of concrete.
But they work easily in tight areas where the larger units can't manoeuvre, such as in corners and close to walls.