Preparing Cement for Epoxy Coating
It is important to prepare a cement floor before applying epoxy coating to ensure that the epoxy will last longer. There are several ways to prepare concrete for epoxy coating.
Shot blasting is a process in which special equipment is used to help prepare the concrete or cement before epoxy paint can be applied. Only trained professionals use this method because it requires special training skills. Shot blasting can remove sealers on concrete services.
Sand blasting is the process of propelling very fine bits of material, usually sand, steel grits, copper slags, walnut shells, at high-velocity to clean or etch a surface. Just like Shot blasting, equipment is used for this method.
Grinding is another method used to prepare cement for epoxy coating. Grinders are used to clean and remove existing coating on the concrete. Usually a diamond grinding disk is used although there are other types of abrasive disks, this one is commonly preferred. Acid etching is the most serious surface preparation method available for do-it-yourself enthusiasts because it does not require the use of special equipment and can be easily achieved.
Chemicals such as muriatic acid, phosphoric acid or sulfamic acid are used to prepare the cement for epoxy paint. Extreme caution should be practiced when using this method because the chemicals can cause severe harm if not used or diluted properly. Since acid etching is the method that can be done without the use of equipment to prepare cement before applying epoxy paint, here is the step by step guide on how to do it properly.
Step 1 – Clean the Cement Floor
The first thing you need to do is sweep or vacuum any dirt or dust on the surface. After making sure that dirt and dust has been vacuumed or swept, wash the floor with a liquid soap or detergent. Watch out for areas that create water beads, this means that that area needs more cleaning because it may have grease or oil on it.
Step 2 – Choose an Acid Solution
Please use a mask before proceeding. Only use plastic or acid resistant containers, and remember to add acid to water and never water to acid. If using muriatic acid, dilute 10% to 15% with water, use 1 gallon for every 40 to 50 square feet. If your choice is the phosphoric acid, a 20% to 40% Phosphoric acid solution should be okay. Sulfamic acid is a white powder that should be dissolved in hot water. Mix a pound of sulfamic acid with 1 gallon of warm water to treat 300 square feet.
Step 3 – Apply the Acid Solution to the Floor
You can either pour it from a can or use an acid proof pump spray unit. Spread the acid evenly. Wait for it to settle for 5 to 10 minutes.
Step 4 – Rinse the Floor
Mop up excess water and dry cement. When the cement is completely dry, you can vacuum once more.
Step 5 – Apply the Coating
When you are satisfied with how the cement has been cleaned then now you can apply the epoxy coating.