Problem Solving Forum
February 11 - February 15, 2019
Can you provide recommendations on ways to make sure an acid stain can be successfully applied to an existing horizontal concrete surface? I understand that residues such as coatings, curing agents, waxes, or other materials will interfere with the stain’s reaction with the concrete, but can I find out what the substances are so I know how to remove them?
Clay Carson of Act One on
February 20, 2019:
I tend to agree with Zenith. In general, do your c ...read more I tend to agree with Zenith. In general, do your client a favor by walking away. Vertical grinding, while theoretically possible as a prep method, is miserable on knees and shoulders. And then you face the gravity issue - how can you follow directions to 'keep the surface wet for x minutes'? You'd have to keep applying it as it keeps running down the wall. The only time it might be worth trying is a small area, a highly motivated client, a very large hourly budget, and mainly a sense of artistic adventure. In other words, a client who says 'I know, but I NEED to have this 10 square feet of artwork in my living room and I'll pay you regardless of how ugly it comes out, half upfront'...
Zenith Czora of Durotech Industries, Inc. on
February 16, 2019:
Acid stain cannot be applied to any surface that a ...read more Acid stain cannot be applied to any surface that already has a concrete sealer or curing agents or is treated with penetrating water-repellent or is an older concrete surfaces where free lime already leached out. Surface preparation and the condition of the concrete itself will determine the outcome. In order to have a successful concrete staining, the acid stain should penetrate into the concrete, allowing the carrier acid to react with the free lime in the concrete. Removing old coatings, sealers or waxes from the concrete surface are not good enough to unblock the pores on the concrete surface unless you grind the concrete, making it porous enough to allow penetration of the acid stain.