We’ve all seen amazing epoxy pour videos and beautiful finished river tables on social media. But what does it take to get those perfect results?
Surface preparation is one of the most important aspects of any epoxy coating project. It’s also often the most overlooked. There is nothing more heart breaking than seeing a beautiful epoxy floor start to chip and break shortly after completion. Most of the time this is due to poor surface prep. Consider checking their epoxy floor map listing for comprehensive services and expert guidance throughout your epoxy project.
Epoxy is a material that does amazing things. It acts as everything from a filler to a coating and adhesive, offering exceptional strength, chemical resistance and dimensional stability. It is a powerful solution that has ushered in a new wave of modern hard working surfaces.
Despite the fact that epoxy sticks to just about anything, it requires proper preparation on the substrate in order to adhere well. There is nothing more heart breaking than watching a client’s beautiful epoxy floor begin to chip and break just a few weeks or months after it was completed. Almost always these chips and breaks can be traced back to poor surface prep.
There are many different methods of preparing a substrate for epoxy, but one thing that all professionals agree on is the need to thoroughly clean the substrate. This means that the surface needs to be sanded down and cleaned in a way that will remove all dirt, grease or oils. Once the surface is sanded down, it should be rinsed with water in order to ensure that it is completely clean. The rinsed water should also be used to remove any lingering dust or debris.
The next step in proper substrate prep is a seal coat. This is a coat that is applied to the surface in order to create a barrier that will prevent air from escaping during the flood coating or deep pour coating process. This will greatly reduce the amount of craters and blemishes that can appear on the finished product.
It is also important to note that the seal coat must be left to cure until it is tack free. Once the seal coat has cured, it will have a very slight tacky consistency that is comparable to masking tape. This is the point at which it is ready to be coated with more epoxy. As long as the room temperature is within the manufacturers specs, this will allow for a strong primary (chemical) bond to form between the two layers of epoxy. It is also worth mentioning that the more porous the substrate, the more likely it will need a seal coat.
Clean Work Area
The work area and all of the tools used must be kept clean. This is a major factor in the success of an epoxy application, and one that many people overlook. It is possible for contaminated hands to transfer contaminants from the epoxy mixture to a newly coated surface, and this can cause blemishes or poor adhesion in subsequent layers of the epoxy coating. The best practice is to avoid touching surfaces with bare hands until they are fully cured. Even then, this should be done as seldom as possible. The oils produced by human skin can contaminate the epoxy and create problems.
The working environment must be adequately ventilated to prevent overheating and condensation. This is especially important when applying multiple coats of epoxy, as each successive layer requires adequate ventilation to cure properly. The ambient temperature of the work site should also be taken into account, as higher temperatures can reduce the epoxy’s open time. In this case, it may be necessary to use a slower hardener or to mix smaller batches of the epoxy in order to extend its open time.
It is a good idea to store the epoxy in a clean, plastic or metal container rather than a glass or foam one. A clean container will help to keep the epoxy’s color consistent and free of stains and marks. It is also a good idea to store the container in a cool location to allow it to come to room temperature before use, as this will extend its open time.
When it comes to preparing a substrate for epoxy, a thorough sanding is the first step. This will provide a good mechanical ‘key’ for the epoxy. It is a good idea to thoroughly sand hardwoods and non-porous surfaces with 80-grit aluminium oxide paper to a dull finish, and to remove all dust from the surface after sanding.
Some materials, such as polyethylene and polypropylene, are impervious to acetone, and epoxy will not bond to them. For these types of plastics, a flame oxidising procedure can be used to improve the adhesive properties of the material and ensure good adhesion.
In addition to clean surfaces and tools, it’s vital that you wear proper hand protection when working with epoxies. Epoxy resin systems contain many chemicals including solvents, hardeners, and fillers, which can cause skin problems if they come into contact with your hands. Gloves offer the most effective way to prevent such contacts. It is best to choose gloves that are chemically resistant to the specific mixture of ingredients in your epoxy system. A table in the MSDS (Material Safety Data Sheet) can help you to select the best gloves for your specific application.
Nitrile gloves offer an excellent level of chemical resistance and are the best choice for handling epoxies. They are also harder wearing than Latex and do not irritate sensitive skin. Some people also use cloth gloves under their nitrile gloves to provide extra gripping power and reduce the permeation of epoxy.
Be sure to clean your gloves regularly. Wash them in running water and a mild soap like GoJo or an alcohol-based hand sanitizer. Always use a fresh pair of gloves after cleaning and before using again.
When you’re working with a new set of gloves, a quick test can be helpful to see how well they work with your particular type of epoxy. You can test your nitrile gloves by trying to pick up a piece of sticky tape and if the glue easily comes away then they are ready for you to start work on the surface.
You can also test the permeability of your gloves by spraying them with a chemical such as acetone. Acetone goes right through the gloves, so if it stays on the glove you’ll need to change your gloves or get some that are more chemically resistant.
Before applying an epoxy coating, you should sand the surface to remove any loose debris and create a texture that will “key” into the epoxy. This will help ensure a strong bond and longer product life.
Be sure to follow all product instructions and review a copy of the MSDS for your specific product. If you need help obtaining an MSDS, ask your product supplier or call the manufacturer’s customer support line.
Although epoxy can withstand the use of many different chemicals, you will need to keep your tools and equipment clean as you work. This will help to prevent bubbles that can form on the epoxy surface during and after application. Gently passing a heat gun over the surface can help to dissipate these bubbles and make your finished surface look better.
It is also important that you do not touch the project surfaces with your bare hands. This is because human skin contains natural self-protective oils that can end up tarnishing the epoxy coating over time. Instead, wear gloves. The best type of gloves to use are butyl gloves because they are highly resistant to abrasions and chemicals.
When working with epoxy, it is also recommended that you use a respirator and work in a well-ventilated area. This is because epoxy produces volatile compounds during the curing process. These compounds can irritate the respiratory system and cause headaches. In addition, the vapors from the epoxy can also irritate the eyes and nose.
It’s also important to note that epoxy is a flammable material. As such, it should never be applied in an area that is not properly ventilated or protected with a fire suppression system.
In addition to the environmental and safety precautions outlined above, you should always follow the manufacturer’s instructions, warning labels, and MSDS sheets when working with epoxy and other chemical products.
The surface you are bonding to must be free of any loose panels or areas where the substrate is buckling or shifting. It is also important that the ambient temperature of the working area be within the manufacturer’s specifications.
Lastly, if you are applying the epoxy to a wood surface, it is important that it be solid and free of any loose, cracked, or peeling areas. This will ensure that the epoxy can adhere properly to the surface.
You should also lightly sand the wood surface with 80-grit aluminum oxide paper to abrade the surface and create a rough texture for the epoxy to “key” into. After sanding, you should wipe down the surface with a lint-free cotton rag wetted with denatured alcohol. This will remove any waxes or other oily contaminants that may interfere with the adhesion of the epoxy.