Leica Geosystems’ Guidance System Speeds Slope Cutting by 30 Percent

Wed August 10, 2011 - National Edition

Leica PowerDigger 2D used to precisely cut slopes.
Leica PowerDigger 2D used to precisely cut slopes.

An Oregon excavating contractor has found that a 2D guidance system from Leica Geosystems improved the productivity of an excavator by 30 percent when cutting slopes to a precise grade.

About a year ago, Pihl Inc., a grading and excavation contractor based in Banks, Ore., bought the PowerDigger Plus guidance system from Leica Geosystems and fitted it onto a Kobelco 235 excavator. The system features a display screen in the cab that shows actual bucket position relative to the design grade.

“The guidance system has done a very nice job for us,” said Matt Pihl, owner of the company. “We use it to cut a lot of slopes. If you have a certain slope to cut, it has to be done precisely. You can make a big mistake if you make one gouge into the slope.

“The PowerDigger makes our excavator 30 percent faster when you’re on the final grade,” said Pihl. “But the best thing is that it eliminates a grade checker. That saves us significant money. And it’s safer, because you don’t have somebody walking around the moving equipment.”

Pihl recently used the guidance system to help cut a 1:1 slope involved in the site preparation for Progress Ridge, a 14-acre retail shopping plaza in Beaverton, Ore. The big 1:1 slope measures 30 vertical ft. (9 m) from top to bottom and is 400 ft. (122 m) long. To cut the slope, Pihl used two excavators — a Komatsu PC 450 and the Kobelco 235 with the PowerDigger guidance system. The Komatsu began the mass excavation by loading two off-road trucks and building a bench about half-way down the tall slope.

Next Pihl positioned the Leica-equipped excavator on the bench and cut the 1:1 slope exactly to grade.

“Then we cut out the first bench with the big excavator, and also used it to cut a second and final bench below the first,” said Tomas Zilka, Pihl’s surveying manager. “After that we could move the Kobelco down to the second bench and finish cutting out the slope.

Zilka was pleased with the PowerDigger Plus.

“For our purposes it is absolutely perfect,” he said.

For more information, visit www.leica-geosystems.com/machinecontrol.