How to coat a concrete countertop 

EX-74 ADVANTAGES:

EX-74 is an extremely clear, tough, high gloss surface coating formulated to produce a deep glass-like appearance in a single layer on a sealed surface. Two or more layers are often applied for added depth and protection. EX-74 has been formulated for improved UV resistance to reduce yellowing and surface degradation from UV exposure. EX-74 has an extended  “open time” which allows up to 5 minutes in the mixing container at 70*F  and up to one hour working time on the surface being coated. EX-74 is waterproof, heat & alcohol resistant.

PREPARATION: 

Protecting work area: Cover all exposed cabinets, etc. with plastic drop sheets before starting your project. Tape in place as required. Note, many of the chemicals used during this process may damage the cabinets and their existing finish if not protected.

NEW CONCRETE COUNTERTOPS:

Newly poured concrete surfaces should cure for a minimum of 28 days prior to coating. This allows moisture to dissipate from within the concrete. Coating too soon will often result in a slightly cloudy or gray appearance between the coating and the concrete as well as pour adhesion; this is due to trapped moisture. Once the concrete has cured 28 days and is thoroughly dry, the surface will need to be abraded with a low-speed grinder or belt sander with diamond grit. Note, concrete supply outlets and some rental companies offer various grinding and diamond polishing equipment. Once the surface has been evenly abraded, vacuum, then acid etch the entire surface. Acid etching helps to remove containment’s which may prevent good adhesion. Acid etching is done with a 50/50 solution of Muriatic Acid and water, applied with a sponge. After etching rinse area with water. Make sure that all safety precautions are carefully understood and in place prior to this procedure. This includes protective eye-wear, rubber gloves, protective clothing, and shoes. Proper ventilation is required during this process. Important; Allow the concrete to dry thoroughly 924 to 48 hours) before proceeding to seal/coating.

EXISTING CONCRETE COUNTERTOPS (finished):

If the concrete top was previously finished, one should remove the existing surface with an abrasive. For good adhesion, one must cut into the concrete surface with a low-speed grinder or belt sander using diamond grit. Note, concrete supply outlets and some rental companies offer various grinding and diamond polishing equipment. As with most projects, proper prep and cleaning of the surface is the key to a successful job. If the concrete counter has been in service for some time, it is essential that great care is taken in removing all stains, grease, wax, etc. Multiple cleanings may be necessary with a strong grease remover, specifically around stove tops! Once the surface has been cleaned, degreased and abraded, vacuumed, then acid etches the entire surface. Acid etching helps to remove contaminants which may prevent good adhesion. Acid etching is done with a 50/50 solution of muriatic acid and water, applied with a sponge, After etching, rinse the area with water. Make sure that all safety precautions are carefully understood and in place prior to this procedure. This includes protective eye-wear, rubber gloves, protective clothing, and shoes. Proper ventilation is required during this process. Important; Allow the concrete to dry thoroughly (24 to 48 hours) before proceeding to seal/coating.

SEALING:

Sealing the surface: Exposed concrete is not uniformly porous and therefore will absorb EX-74 at different rates. You may find some areas have completely absorbed the coating, While other areas have not. To avoid this uneven absorption issue, apply two or three thin seal coats. To seal the surface, measure and mix approximately 2 ounces per square foot. Pour onto the surface and spread with a stiff piece of card stock or plastic spatula. There should be just enough material to “wet” the surface without any build or thickness. Apply to the entire top area and sides as required. Remove all excess material. Allow this surface seal coat to cure 24 hours, then apply a second seal coat in the same manner and allow it to cure. The second seal coat now cured, should have a slight uniform sheen with no dull or flat spots. If dull or flat spots appear, then repeat the process until the surface has a uniform sheen when cured.

CAUTIONS:

Extreme heat from stovetops set into a countertop may cause the cured surface to discolor. Avoid placing hot items directly onto the surface as this may result in discoloration or blistering. Do not cut directly on the cured surface as this may damage it, always use a cutting board.

COATING:

Before measuring EX-74 ensure that the resin & hardener bottles are slightly warm to the touch (70*F). If not, place both bottles in warm, not hot water for 5 to 10 minutes prior to using. As a result, the resin and hardener will measure easier and mix better with fewer bubbles.

(1). Measure EX-74 in exact amounts by volume. Do not guess at the proper ratio or just empty the two bottles into your mixing container. Unless you measure equal portions of resin and hardener, your ratio will very likely be inaccurate, resulting in a soft sticky coating! Determine the amount of fluid to be used by measuring the top and sides of your project. On average use 4 to 6 ounces of EX-74 per square foot. EX-74 will not level correctly if spread too thin.

(2). Mix measured resin and hardener in a clean, straight-sided, flat bottom container. Stir until thoroughly blended scraping sides and bottom continually while mixing is a must! Mixing should be completed after 2 minutes of vigorous mixing. To ensure a thorough mix, have two mixing containers ready. Begin mixing in your first mixing container, After one minute of vigorous mixing, transfer contents into a second mixing container continue mixing for two minutes. Improper mixing will result in soft or tacky spots that will not cure! We do not recommend mixing more than one gallon of fluid at a time.

(3). Pour, do not wait! Pour as soon as thoroughly mixed. Pour over the surface in a circular pattern. Start close to the edge and work towards the center of your work. This will allow the EZ-74 to level from the center out to the edges of your work surface. Help spread where necessary with a stiff piece of paper or plastic spatula. Be careful not to spread too thin resulting in a wavy surface. Use a helper for mixing and pouring large objects. One person can mix while the other pours the coating. Caution; If EX-74 is left in the mixing container, it will become hot and set up rapidly!

(4). Working time with EX-74: If you pour immediately after mixing, you will have approximately 25 minutes of working time at 70*F, less time for warmer temperatures.

(5). Removing bubbles: Within 10 minutes of pouring, air bubbles created while mixing will rise to the surface and begin to break. Exhaling across the surface at this point will break bubbles. However, on large surfaces, the use of a small propane torch is the easiest and most effective method of removing air bubbles. The reason for this is that EX-74 contains no flammable solvents. The carbon dioxide-rich exhaust gases from a propane flame effectively release trapped bubbles. With a moderate flame, pass the torch over the surface with a swift, even, sweeping motion. Never hold torch closer than 3 to 4 inches from the surface. Sweep past the ends of your work so that the torch never stops on your fresh coating! Avoid over torching which may scorch the surface. Warm room temperatures will result in better bubble release. Note: We do not recommend the use of a hairdryer for removing bubbles. Hairdryers will blow dust from the surrounding air onto your work! Caution; Although Ex-74 contains no flammable solvents, the objects you are coating, as well as surrounding table covers, etc. may be flammable.

(6). Cover your work: Use a plastic drop cloth to keep dust and lint particles off while EX-74 sets.

(7). Flat straight edges: After a number of EX-74 coats, wide flat edges can become slightly wavy, Sand the wavy edge flat using 120 grit sandpaper. Wipe edge clean and apply your final flood coat. Do not sand in your clean coating area.

(8). Drips: Drips that have accumulated on the bottom edge can be removed by sanding after the EX-74 hardens. To easily remove drips, apply 2” wide plastic tape to the bottom of project along edge prior to the coating surface. Do not use masking tape. Press firmly to work out trapped air. Once the surface is coated and cured, use a sanding block and sand through the coating on the bottom edge. Then peel the tape off removing drips!

SURFACE CARE:

Furniture polish will prolong the life of the surface and remove smudges, etc. Heavy objects, when left for a period of time may leave impressions on the Ex-74 surface. Once the objects are removed, the impression will disappear in a few hours at normal room temperatures.