Walk-behind grinders are widely available for grinding slabs and floors, from single-disc machines for working in small areas to dual-, triple- and four-disc machines for grinding large slabs at high speeds. Single-disc grinders cover ten to twelve inches in one pass, while dual-disc machines cover more than 20 inches. The rotation speed of a disc can range from 250 to 3,000 revolutions per minute. Multi Disc grinders usually have discs that counterrotate to provide balanced torque so the grinder won’t pull from side to side.
In order to produce more even grinding, some machines are also equipped with floating heads that follow the contour of the floor and adjustable wheels on the rear for leveling grinding discs. Most manufacturers offer a selection of power options, including electric, gasoline, and propane. Some machines are equipped with vacuum ports for dust-free dry grinding. In some models, you can also attach wet- or dry-cutting attachments using the water mist system.
Grinders for Hand-Held Use
You can buy handheld grinders for working in tight places, such as corners and close to walls, where larger units cannot maneuver, even though walk-behind machines are best suited for profiling large slab surfaces. With grinding diameters ranging from five to twelve inches, these machines are ideal for smoothing vertical surfaces and grinding concrete countertops, as well as removing bumps, form marks, and graffiti. Portable units have the same kind of grinding accessories as their larger cousins, and they can also be connected to an industrial vacuum system for dust control.
How To Use A Concrete Floor Grinder
Grinder models of today can typically handle multiple functions, and are generally more adaptable than other types of surface prep equipment.
The following applications are suitable for concrete grinders:
- When applying thin coatings or paint on floors, profile them so ridges will not appear, as can happen with scarifiers
- Removing dirt, grease, and other industrial contaminants
- Leveling uneven joints or high spots
- Removing paint, sealant, or any other coating
- Polishing concrete surfaces (grinders with finer-grit abrasives)