In order to bring a concrete floor to a high polish, concrete floor grinders must be used to remove fine particles of the concrete. Choosing the best concrete floor grinders starts with determining the size of the job or jobs you will perform, as well as the frequency. These machines can be quite expensive, so you will need to decide if it will be worthwhile to buy new, buy used, or rent. If you will only be doing one project, it is best to rent, but if you own a business or will be doing jobs frequently, consider buying.
The size of the job or jobs you must do will dictate which sizes of concrete floor grinders will be best for you. Exceptionally large floors, such as garage or basement floors, will require the use of a much larger unit, while small slabs may require a small unit or even an edging unit. Edging units are designed to fit into tighter spaces and corners, making it an appropriate machine for getting into the spaces a large grinder cannot reach. It may be necessary to rent or buy more than one type of grinder to accommodate your needs.
The smallest type of concrete floor grinders are handheld and can be used for other types of concrete projects as well. Handheld angle grinders can be fitted with the appropriate grinding discs for grinding concrete; these smaller power tools are great for getting into tight corners and other tight spots a larger unit cannot reach.
Look for concrete floor grinders that feature dust collection systems. When concrete is ground dry, a significant amount of dust will be raised, and it will contain silica. Silica is dangerous to breathe in and can damage the lungs, so it is important to collect most of the dust before it enters the air. A dust collection system on the unit will help prevent excess dust build-up, though it will still be necessary to wear a breathing mask and eye protection when operating any concrete floor grinders that are grinding dry.
Concrete can be ground wet, as well, which helps abate some of the dust created by the grinding process. If you intend to grind the surface of the concrete when it is wet, be sure the machine you choose is intended for wet grinding. Most manufacturers will clearly state whether the machine is appropriate for dry grinding, wet grinding, or both.