What Is Car Body Glass Coating?

Glass coating is an inorganic material made of a Silica or a Quartz-Silane-based compound. It is used to protect the painted surfaces of car bodies. It is less likely to stain. Unlike traditional wax, its luster and protection can be long-lasting once it is applied. This is because they do not contain materials that oxidize (bind with oxygen). Oxidation weakens the original protection and shine of many car products, thus rendering the car surface prone to damage. It is easy to maintain, provides clean, shiny surfaces and long-lasting protection.

What is the difference between coating and wax?

The main component of wax is carnauba wax oil, which is extracted from palm trees. In recent years, some waxes have added petroleum. Higher quality waxes contain more carnauba oil. Carnauba wax is oil based, so it has water-repellent characteristics and can obscure scratches. However, there are also disadvantages. Waxes can easily become dirty because oil has a high viscosity (thick and sticky). This means dirt can stick to it. Also, wax can easily melt and deteriorate because it is sensitive to heat. Sunshine or engine heat can promote deterioration and cause wax to melt off the car’s surface. Wax can also break down in the rain or when the car is washed.

On the other hand, coating has a chemical composition of silicon, silica, fluorine and titanium. These molecules form a film coating that penetrates between the molecules of the car’s painted surface, creating a very powerful protective layer. Resistant to dirt, heat and rain, coating’s protection and shine will last over a longer period than wax.

There are various kinds of coatings that range in application complexity from simple, which any consumer can apply, to products for professional use only.

During its application, if the car’s surface is dirty and rough, materials will not adhere to car body paint, so surface preparation before application is important.

Types of Glass Coatings

Glass-based coatings can be broadly divided into two categories: quartz-silane based coatings and silica-based coatings.

The quartz-silane-based glass coating, also known as “completely cured glass film type” achieves very high gloss and strong durability. It protects the car body by creating a cured coating of silica on the car’s surface. However, it takes about three weeks for the coating to be fully cured, which is a drawback. It is also expensive because it takes a long time for the product to be formulated.

The silica-based glass coating, also known as “glass fiber type “, also makes a film, coating the surface of the car body. It is fixed to a silicon polymer molecule. It is an easy formulation and, therefore, is costs less to produce. However, its durability and water repellency is inferior compared to the quartz-silane-based.

In addition, some of the fluorine-based coatings, such as Teflon, are used to coat car bodies. They are excellent in durability. However, they are inferior compared to glass coatings and more expensive to formulate. As a result, glass coatings are on the cutting edge of technology’s focus of exploration.

A Glass Coating Hybrid

Currently, there is debate about whether hydrophilic (attracts water) products are more effective than hydrophobic (repels water) products for car care. Glass is hydrophilic. The new types of glass coatings are hybrids, adding a silicone resin layer to the existing glass layer to change the hydrophilic trait of glass to hydrophobic, thus creating a strong water repellant product.

Drop Coating Metallic Auto Body Paint

Drop coating is an important skill that every auto body paint sprayer should aspire to master. Drop coats are administered during the last phase of the spraying process when metallic paints are used. When applied to an auto body panel correctly, drop coats offer full color coverage, perfect metallic content distribution and a better paint base that can accept lacquers with ease.

Applying Metallic Paint

Drop coating should be used with all metallic auto paints. Many paint sprayers apply metallic base coats using the same methods with which they apply solid colors, and this is a common error that compromises an otherwise perfect job. While horizontal arm movements are perfect for most solid color spray jobs, metallic auto body paint should be dropped onto the panel as soon as basic coverage has been achieved, and it is equally as important to cross coat the final application in horizontal and vertical directions.

Ensuring Uniform Paint Coverage

Before drop coats can be applied, the prepared car panel must be adequately covered with metallic auto body paint to help avoid primer transparency. Once the color is activated, a full wet coat of paint should be sprayed to the surface of the panel. It is essential that each horizontal spraying movement blends into the previous one to guarantee uniform coverage and distribution (overlaps of 30% to 40% are perfect). As soon as a single we coat has been applied, the auto body paint must be left to dry for around 10 minutes. Never spray a second coat until the first one has achieved a matte appearance.

Applying a Second Coat of Metallic Paint

Personally, I like to spray the next coat of paint in a different direction to the first, especially when the panel has been taken off the car. Sometimes, this isn’t possible on vertical panels, such as fenders and doors, if they are still fitted to the vehicle so don’t be too concerned if you are happier using a typical horizontal spraying pattern. The second application must be sprayed in a similar manner to the first coat, but try to achieve 80% wetness in comparison to the earlier application. Once more, the auto body paint must be left to dry for around 10 minutes until matte.

Applying the Drop Coat

If the metallic paint is still transparent, an additional coat may be required but this won’t be necessary in most cases. To spray the actual drop coat, position the spray gun 18 to 24 inches away from the surface of the panel and reduce gun pressure by 20% to 30%. Spray the auto body paint horizontally, moving the arm slowly across the panel so the metallic color drops (or falls) onto the surface. Maintain uniform coverage until the spraying process is complete. Recoat the panel from a similar distance straight away, but swap the horizontal movements for a vertical direction so the subsequent coat crosses the first. As well as guaranteeing even paint coverage, crossing the drop coat offers uniform metal distribution and a superior surface that will accept lacquer correctly.

Tacking the Drop Coat

Allow the drop coat to dry before visually inspecting the metallic auto body paint. Check for patches where coverage might be inconsistent and spray a further drop coat if necessary. With solvent-based auto body paint, it is always a good idea to run a tack rag over the vehicle panel as soon as the drop coat has dried. Specialist tack rags can be purchased for water-based auto body paint, but it is preferable to waive the tacking process as high paint build-up can peel back the color and this can lead to frustrating rework.