Using the correct size and shape of silica sand is very important to each specific coating or repair product used in tennis court resurfacing. The right kind of sand is integral to the performance of each tennis court coating, patch material, or crack filler. Without the proper sand type and amount, a coat cannot achieve its purpose.
Tennis Court Coating Coverage Rates
Tennis court coatings are squeegee applied. The squeegee floats at the highest point of a coating, so if you are using a larger silica sand, the squeegee rides higher. This will generally yield a thicker coat and use more coating, unless there are lots of asphalt voids and the sand it pushed down into them. If a finer sand is used, as in the color coats, you will use a little less material and put a thinner coat.
Silica Sand for Acrylic Resurfacer and Acrylic Patch Binder (50-60 Mesh)
The size and shape of silica sands both have a specific purpose. The lower the number, the larger the particle size (in the AFS scale of measurement). Since Acrylic Resurfacer and Acrylic Patch Binder are both filling voids in asphalt and concrete, the larger mesh size is better. Also the angular shape allows the sand to key together and form a nice, strong base film or patch. Acrylic Resurfacer is also designed to provide a consistent, but somewhat rough surface. This helps the color coating grab on and apply at the correct thickness for good coverage and long wear.
Silica Sand for Tennis Court Color Coatings and Line Paint (Rounded 80-100 Mesh)
The silica sand that is commonly used in color coatings is finer and mostly rounded. The rounded shape helps the sand to roll under the squeegee, instead of dragging through like a small stone that fell into the puddle. This helps to minimize surface streaking and provide a smoother, blemish-free surface. The smoother finish also reduces the amount of tennis ball fuzz, which creates more housekeeping issues in indoor tennis clubs and facilities.
SportMaster tennis court coatings are manufactured with fibers, which will also minimize tools marks and streaks in the color coatings. The use of fibers is a big help, since many court owners and players are looking to slow down the play by using larger and more angular-shaped silica sands in the colored tennis court surface coatings. The fiber-containing formula of SportMaster enables them to have the surface speed they want, with less streaking than most other brands.
Acrylic Resurfacer is a product that is commonly used when resurfacing tennis courts and other sport surfaces. All major manufacturers of acrylic sport surfaces produce this product and recommend using it on both new and existing court surfaces. Even though many installers think of Acrylic Resurfacer as a primer, it serves specific purposes not entirely related to good adhesion.
First of all, Acrylic Resurfacer is a filler coat. It is designed to suspend large amounts of silica sand for the purpose of filling minor voids in the surface. Asphalt is a common pavement used for tennis court construction. Mostly comprised of asphalt binder and rock, asphalt can exhibit a wide variety of porosity from one location to another. Many factors can influence the pavement porosity, from available regional and local sources of aggregate to project specifications. Acrylic Resurfacer can fill the surface voids to produce a tight surface without voids and pits that show through the pigmented surface layers. If the surface voids are not properly filled, they can lead to some of the following problems:
- Pitting on the playing surface
- Surface pinholes that are created from air in the voids during application of tennis court color coatings
- Poor coverage rate on the pigmented surface coatings
Secondly, Acrylic Resurfacer creates or restores texture to the surface prior to application of the colored surface coatings. Existing acrylic sport surfaces tend to become smooth with years of wear. The fine silica sand that was in the coating eventually rolls out and the acrylic color surface becomes polished and smooth. The resurfacer uses an angular sand to create a sandpaper-like texture to better accept the color coating layers. The colored tennis court surfaces contain a very fine, rounded sand to minimize surface streaking and application marks. If resurfacer is not applied to create proper texture, the color coating can be applied too thin by the application squeegee. An example for comparison would be cleaning a glass window with a squeegee. Since the window is very smooth, the liquid glass cleaner is wiped almost completely off. If there is no texture on a tennis court, the surface coatings will not be applied in an adequate thickness. This will minimize film solids and shorten the life of the court surfacing system.
With its heavy body, one or more coats of Acrylic Resurfacer can also be used for shimming rough surface repairs, and hiding patches from depression or crack repairs. After application, resurfacer dries to a firm, hard film and can be scraped and sanded prior to application of the acrylic color surfacing coats.
Finally, the only situation where Acrylic Resurfacer is not required is when you have an existing acrylic surface with adequate texture. This occurs when the courts have been properly maintained and resurfaced before the original texture is lost. Visit SportMaster for a tennis court maintenance manual and for further care instructions on extending the life of the sport surfacing system.