Case Study: Hulbert Finish Grading achieves pinpoint accuracy and on‑schedule grading with Trimble GCS600

Trimble Technology Tames Rugged Site

Hulbert Finish Grading, a Phoenix-based contractor, was hired to build a 130,000 sq. ft. Home Depot pad on an 88-acre, hilly Payson, AZ site riddled with granite outcroppings and steep 3:1 slopes. The crew faced severe weather (heavy rain and snow), tight drainage and property-line constraints, and a $16,000/day liquidated-damages deadline while needing subgrade accuracy to ±0.25 inch.

They installed Trimble’s GCS600 Grade Control System on a Komatsu LaTerra GD655-3 motor grader, using more durable masts, protected sensors and a higher-performance receiver to achieve full 100% cross-slope control and quick transmitter reacquisition. The system kept the project on schedule despite the weather, produced exceptional precision (survey checks averaged within 0.02 in. across the pad), reduced manual layout time, and handled the rocky, steep terrain—results that convinced Hulbert to continue using the GCS600.