Acid Stain Technique
- 1). Combine 1/4 cup TSP with a gallon of warm water in a bucket. Put on a pair of rubber gloves and dip a large scrub brush into the mixture. Wash down the concrete, removing caked-on grease, dirt and oil. Re-dip your scrub brush as necessary to ensure you do a thorough job.
- 2). Rinse with a hose and check for water absorption. If you see water beading on the concrete in any area, that means that area is not going to absorb the stain. Thus, you'll have to wash again with TSP.
- 3). Tape off areas that you don't want the stain to penetrate. Use painter's tape and drop cloths if necessary. Create a 3 percent stain dilution with three parts stain and 97 parts water in an acid stain sprayer. That's about 4 oz. of acid stain for 1 gallon of water.
- 4). Shake the acid stain sprayer well. Put on protective eye wear. Spray the acid stain in a circular motion from left to right, gradually covering the concrete. Let the stain dry completely. Add a second coat with the same amount of stain and water, or add a higher percentage of stain for a darker color. It's up to you and what results you desire.
- 5). Apply the second coat in the same manner, spraying in a circular motion, moving from left to right, until you cover all the concrete. Allow it to dry completely.
- 6). Apply two coats of nonyellowing sealer for outdoor or indoor uses, depending on your needs. Apply the sealer with a nylon brush for smaller jobs or a paint roller for larger jobs.
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