Concrete is a semi-liquid or plastic state of matter when it is freshly poured into a wall form or horizontal slab. Concrete must be helped along by using tools specifically designed to place and finish it. Wall pours use concrete vibrators to consolidate the plastic concrete to minimize ‘honeycombing’, which is air trapped along the surface of the forms that leaves ‘bug holes’ on the face of the walls after the wall forms are stripped. Vibrators can be gas powered or electric. Electric vibrators are typically powered by generators and long lengths of extension power cords, all can be supplied by A.H.Harris. Finishing tools such as hand trowels are used at the top of the wall to smooth out any irregularities that will be seen in the final product. Wall form scrapers are typically used to clean the faces of the forms after they are stripped from a wall pour. Wall form stripping tools are used to release the forms from the initial bond the concrete has on the form face. Wall tie break-off tool snaps off the part of the wall tie that is exposed past the face of the wall. A.H.Harris carries several brands of vibrators and concrete finishing tools and our team is looking forward to discuss your options in person or over the phone. Horizontal concrete slabs on grade or elevated structural concrete slabs have an exposed top surface that will be finished to the project specifications. The following tools are typically used:
- Cumalongs: Used to drag or push concrete along a horizontal surface.
- Bull Floats: Used as the ‘first pass’ finishing tool over freshly placed concrete. Typically, magnesium floats are used on the first pass. This type of float leaves an open face to the surface allowing the surface to breathe so bleed water can rise to the surface and evaporate. Steel floats might follow the first pass to give the surface a ‘tighter’ finish, or smoother surface.
- Finish Trowels: This tool determines the final finish that will be seen and felt and is typically used after bleed water has evaporated off the surface of the slab. Finish hand trowels come in steel, magnesium, and wood. Each type will create a different surface finish. Steel will give the tightest or smoothest surface. Magnesium will leave a more open face not typically seen by the naked eye. This finish will have the least amount of surface problems such as scaling. Wood will leave a rougher surface when friction may be required such as sloped ramps. Edgers are used to create a rounded or chamfered edge to the slab. Groovers are used to create a ‘v’ shaped depression in the surface of a concrete slab that provides a plane of weakness needed to control shrinkage cracking during the curing stage of concrete.
- Power Trowels: A gas powered machine, sometimes called a whirlybird or helicopter that is typically used on larger slabs. These machines come in different models and sizes. There are walk-behinds and ride-on models. Finish blades can be switched out to float, finish, or burnish which creates the hardest and smoothest surface
- Other Tools: Finish brooms leave a concrete surface with a raised profile as can be seen on sidewalks. Tine brooms are used when a more aggressive profile is specified.
Find these and many more concrete tools in our brand new catalog, available free at your local Harris or via delivery to your home or business. We also carry a variety of power tools like concrete saws (e.g. Husqvarna), drills and polishers. See some of the tools in action in our stamped concrete demo video.