This is decorative concrete staining how-to at it’s very basic.
This is part 4 of an on-going series on Decorative Concrete, and is an explanation of the hand-application of RAC stains.
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Hand application of RAC stains, using various methods and tools, can create a nearly endless variety of effects. Alternative application tools, include rags, sea sponges and various sized brushes. The use of alternative methods of applying RAC stains to borders, accents and other small areas, are very effective and add creative touches to your projects.
Brush marks can, in themselves, produce interesting effects; such as hair on a bear, or the look of texture and depth on a geometric design. Brush marks can be diminished or eliminated with multiple coats.
Dabbing in colors with natural sea sponges or rags, leaves a faux, or marbling look. The twist of your wrist, during application, can create yet another different effect.
Allow at least four hours for the RAC stain to fully react. You must then neutralize and scrub the floor. Use either a mix of a one pound box of baking soda and five gallons of water, or a mix of eight ounces of ammonia with five gallons of water to neutralize the surface.
Either of these mixtures should be broomed into the work surface. To remove stain residue on interior floors, you may use brushes with long handles and manually scrub the floor.
Or you may use a floor machine, sometimes called a buffer, with a nylon bristle brush. During and after the brushing, or floor machine scrubbing, you must wet vacuum the liquid residue off the surface.
Failure to vacuum the residue, and get a thoroughly clean surface, could result in a sealer failure at a later date.
Care must be taken to remove all water that collects near the walls. Any standing water along the walls could affect wooden studs and could ruin drywall, baseboards and paint.
A rotary deck washer works well outdoors. Care must be taken when using a deck washer so you do not remove too much color from the concrete. Reduce the pressure to only the amount needed to remove the stain residue from the surface.
Floor machines usually do not work well on groomed finished surfaces, however rotary deck washers work very well. If you do not have a rotary deck washer, use a pressure washer or long handled nylon scrub brushes.
If using a pressure washer, turn the pressure down to minimum. Then increase the pressure as you see that the color is holding and will not wash away. Be cautious with a pressure washer; too much high pressure water, too close to the surface, will leave ugly fan marks.
Rinse exterior walls often. Remember stain residue can discolor surrounding items; such as gutters, sidewalks, concrete foundations and painted surfaces. It may be helpful to pre wet surrounding objects before beginning the residue removal and rinse phases.
Residue can likely discolor gutters. Before the application of rack stains begins, apply a water based clearcoat to any concrete like gutters, walkways and foundations that may be inadvertently exposed to stain or stain residue.
Water based clear sealer is used here, so as not to darken the areas to be protected. To prevent stain freckles from happening, splatters must be removed from the clearcoat of protected areas.
Depending on the regulations in your area, you may need to collect the wash water and properly dispose of it.