How to operate a Motor Grader?
A good operator is essential to maximize cutting edge life. "The operator is the main controller of the wear on the cutting edge, " says Woody Ferrell, Champion Motor Graders. "Make sure you understand what type of application you are operating in for optimal edge life. Harder areas or areas with more rock than dirt will take more operator finesse to keep the edge from wearing prematurely."
Operating technique keeps the edge sharp. "The operator is responsible to make an effort to keep the edge clean and even, " says Phil Newberry, Caterpillar. "By changing the blade tip to the back position, they may be able to sharpen the edge. This will allow for better cutting when the edge is moved to a more forward position. If the operator continues to run in a forward position, the edge will round over and trimming is more difficult. Time spent ripping or scarifying a surface to remove material will extend the life of the cutting edge."
It is all about positioning the moldboard to optimize performance over the job. "Keeping the moldboard straight up keeps a sharp edge, while rolling the blade forward creates a blunt edge, " says Ferrell. "Some precise fine grade operations require rolling the blade all the way forward to get a better view of the backside of the blade and finish grade. Experienced operators will continuously change angles for the application, while the more inexperienced operators will keep the blade rolled forward for better visibility. Think of it as if you are sharpening a knife. You have to work both sides of the edge."
Brian Lowe, Volvo, agrees, noting, "Fine grading is generally accomplished with the moldboard rolled forward, which wears the leading corner of the cutting edge. If the operator occasionally tilts the moldboard back, the wear across the bottom surface is more even — but this must not be done if it affects the final grade."
Grading along curbs and gutters requires the operator's full attention. "When grading along curbs and gutters, an operator may rub up against the curb and damage the end of the edge and the moldboard end bit. Again, this is where an experienced operator is an asset, " says Lowe. "Similarly, a good operator will switch between left side lead of the moldboard to a right side lead, as this helps even out wear on a moldboard edge, extending life in the process. A less confident operator tends to have a 'favorite' side, which promotes uneven wear over the life of the edge."
He continues, "When cutting grade at curbs, experienced operators will watch the wear rate on the first 2 ft. of the leading edge, as this area will experience faster wear rates than the center of the moldboard. Left too long and the operator will be cutting deeper at the middle of the blade — the opposite effect to what a municipal operator experiences."
The operator must pay careful attention to how the blade is being used. "Try to work with an even pressure along the entire length of the moldboard instead of working the first quarter when cutting grade, " says Newberry. "This will greatly reduce the quarter crowns, help reduce the number of passes needed to achieve grade and also keep the cutting edge wear more even. When the cross slope of the grade is good but an additional 1/8th, 1/4 or 1/2 in. needs to be removed, the use of the blade tip will accomplish this."