Laser and GPS systems increase the versatility of pull scraper systems when properly set up. We turned to four earthmoving professionals to get the inside scoop on how they're using grade control to enhance the performance of their equipment.
An efficient, flexible solution
Evans, GA-based Garnto Gearig Brothers Construction is a grading and utility contractor that grades large commercial sites, as well as a few residential projects. "We move anywhere from a million yds. down to 50,000 yds.," says Travis Gearig.
The company uses Reynolds 18-cu.-yd. CMX and 14-cu.-yd. 14 CS scrapers pulled by 436-hp Case IH 430 tractors. "We pull some tandems and some triples depending upon what kind of situation we are in," says Gearig. The six scraper operators vary from two to seven years of experience.
Gearig explains the benefits of the pull scraper systems. "Pull scrapers work a lot better as far as regular dirt, not wet dirt and rock. You don't have to have a dozer pushing like with a rubber-tire scraper. You cut the dozer out, and you reduce fuel consumption," he notes. "[Pull scrapers] are more efficient for hauling up to 3,000 or 4,000 ft. After that, a lot of times, we will get trucks in there."
But even on longer hauls, there are advantages to a scraper system vs. trucks. With the scraper system, one operator can load and dump. "With a truck, you have to have a trackhoe to load it and a bulldozer to knock [the soil] down after you dump it. Then you have to come over it and fine grade it," Gearig points out.
For precision work, a carry-all scraper is equipped with a Trimble laser system. "We can get to half a tenth," says Gearig. "If we have a building pad that you have to get 'dead on,' then we will have the motor grader work with the scrapers." Once the scraper does its pass, the motor grader with a laser performs the final grade to get within a couple hundredths of an inch.
In certain rough grade applications or where the tolerances aren't quite as tight, a carry-all scraper equipped with a Leica GPS has proven effective. "If we are building a lot that [requires] within a tenth, we can have the GPS on the scraper," says Gearig. "You can probably get closer than that, but we don't ever figure any closer than a tenth.
"The GPS is a lot more versatile," he adds. "With a laser, you can only shoot a flat beam."
Some roads raise and drop in elevation. "You really can't do that with a laser unless you check each point with a stick laser," Gearig states. "You just cannot beat the GPS for a road. You are not going to get it within a hundredth, but for rough grading, you can't beat it."
Construction of the electronic maps is outsourced. "They put all of the points in, then we will download that and put it in our GPS," says Gearig.
Once on site, Gearig claims it takes a little less time to set up the GPS system than the laser after you get past initial startup. "If you are starting a job, it takes longer to set the GPS up," he admits. "But once you have all of your points in there, the GPS takes less time."
One trick the company uses to save install time is to cement a pole in the ground for the base station. "We just screw our base station down on it," says Gearig. "So you don't have to go back and reprogram it."
The laser and GPS systems, in conjunction with the pull scrapers, have helped Garnto Gearig Brothers Construction succeed in a competitive market. "We can definitely be more competitive on price than the wheel scrapers," Gearig asserts.
Developing a competitive niche
Reid Laser Leveling, Ontario, Canada, has been in business since 1990. The company started out leveling fields and evolved into construction of large greenhouse sites. "I did one and it just snowballed from there," says Jim Reid.
He recently completed a 30-acre greenhouse project. Precise grading is important on such large sites, because once the water travels to each plant, it moves to the outer edges where it is picked up and sent around again.