We have covered the basics of infield mixes, what makes up a mix, SCR and EST, and drainage, so let’s move on to grading.
Simply stated, laser grading is the use of laser technology to grade an infield. The laser is set up on a fixed point, depending on which type of laser is used, and sends a laser beam to a receiver mounted to a pole on the box blade. As the blade is pulled or pushed across the infield the receiver will direct the hydraulics to automatically move the blade up or down to provide an accurate and consistent grade. How accurate? I like to see +/- 1/8 in.
Typically two different types of lasers are used. A dual slope laser grades in a slope or crown. These lasers are typically used to grade football and soccer fields, but can be used on baseball and softball fields, especially older fields. A conical laser grades in a cone. When a conical laser is used all three bases are at the same elevation. Conical lasers are the industry standard for new infield construction.
As was stated in the drainage post, infields should always be laser graded. After laser grading, especially in new construction, a survey referred to as an existing topographical survey should be taken and reviewed with the owner and contractor. This will assure the owner of the property that the surface was graded properly.
Why is all of this important? As the drainage post explains, surface drainage is the best and only way to effectively drain an infield. If there are irregularities in the grade, i.e. – “bird baths” water will hold in the areas and make the infield unplayable after rain events. Remember – water does not run uphill!
Always ask your grading contractor if they implement laser technology, and ask them to explain their grading plan to you before materials are moved on your playing surface.