In the last article, I discussed the debate between staining and scratching of concrete countertop sealers, and I mentioned the importance of repairing any scratches that do occur.
Omega Concrete Countertop SealerTM is easily repairable by either a professional re-application of Omega or by a homeowner process using readily available materials (automotive clearcoat paint touchup pen). The homeowner process is fully explained in a document available after purchase of Omega. The document is designed for you to print out and give to clients upon installation. There is also a Care & Maintenance document provided.
This article focuses on the professional scratch repair process for Omega. The process is straightforward: first clean the countertops, then sand out the scratches, then reapply at least 2 finish coats to restore the surface.
Step One – Clean the countertops
Evaluate the extent of the damage. The easiest repair is one where the cuts or scratches don’t penetrate the sealer and expose the underlying concrete. These scratches can be handled with minimal effort: simply proceed to Step 2.
If the scratches were touched up by the client using the CCI Scratch Repair Instructions, then the touchup pen clearcoat should be first removed before resealing. Use a paper towel and straight acetone to scrub away the touchup clearcoat, ensuring all of it has been removed prior to resealing. Proceed to Step 2.
If the cuts or scratches penetrate into the concrete, more work may be needed to restore the countertops. All stains and damage must be eliminated before resealing, otherwise, they will be permanently locked into the concrete.
First, remove any stains that may have occurred. Stains (mustard, wine, etc.) can be bleached out using household bleach. Soak a folded paper towel or cotton ball with straight bleach and set it on the stain. Cover with a plate, cup, or glass to keep the bleach from drying out. Check the stain every 15 minutes until it’s disappeared. Clean up with water and a mild cleaner like Windex. Allow the area to completely dry out.
If the scratches are dark but dry, then oil has penetrated into the concrete. This can be challenging to eliminate, as oil is difficult to get out of the concrete. The process is to use a poultice made of baking soda (sodium bicarbonate) and acetone. Make a paste, thickly smear it over the oil stain, and cover and tape down plastic wrap to prevent the acetone from evaporating. Allow the poultice to sit overnight and draw the oil out. The process may need to be repeated to eliminate as much oil as possible. Bear in mind you may not be able to get all of the oil out of the concrete.
Step 2 – Sand out scratches
Once all stains are eliminated, clean the surface that is to be resealed to remove any traces of dirt, oil or other contaminants (like wax). Surface dirt, debris, and oil can be removed by first using household cleaners (Windex, Simple Green, etc.), and then made very clean using a lint-free cloth wetted with a mixture of 50% acetone and 50% water.
Lightly dry sand the surface to be resealed with regular 320 grit sandpaper to remove any ridges in the sealer. Do not sand down to bare concrete. Scratches in the surface will gradually be filled during the resealing process. Evenly sand to achieve a smooth, well-scuffed surface over the entire surface of the slab.
Step 3 – Apply 2 finish coats
Spot repairs can be done, but there may be a sheen difference between the existing surrounding sealer and the new repair. Ideally, you reseal the whole countertop, seam to seam, in order to maintain an even sheen across the whole slab. No priming is necessary. Apply 2 finish coats over the sanded areas.