Blade Pitch

The blade pitch adjustment is a working tool that supports the cutting action of the blade and is hydraulically controlled by a lever in the operator's cab.

Figure 10-21 shows the different blade pitch adjustments.

_{Figure 10-21.-Blade pitch.}

Figure 10-20.-Turning the grader around technique.

For normal grading operations, the upright position on the blade is used. For a greater cutting action, the backward pitch is used. For a greater mixing and rolling action on the material being side tasted, use a slight forward pitch. When spreading, finishing, or maintaining surface material, use a full forward pitch. This pitch accomplishes a partial compaction of the surface materials and assures filling any low spots.

When selecting the correct blade pitch, you have to think about the type of operation, type of material, depth of cut, and speed of operation. Experience and practice enhance your skills to know which pitch positions achieves the best blading results for the type material.

Scarifying

Scarifying is breaking up hard or compacted materials, using the scarifier on the grader. A decision to scarify a road or not depends on the availability of water to obtain the proper moisture content of the material and the amount of traffic that travels the road. The proper moisture content supports the binding of the material required for compaction and is also used as dust control.

Just placing fill material on a dirt road to fill the ruts and potholes is a temporary fix. The fill material does not bind in the ruts and potholes and, therefore, will NOT remain in place.

The proper way to reshape a dirt road full of ruts and potholes is to scarify the surface to the depth of the depressions. This breaks up all the compacted surrounding surface materials. After scarifying the material, blade mix the surface materials, reshape the road, and compact.

Figure 10-22.-Scarifier tooth.

Figure 10-23.-Marking cut.

To scarify extremely hard or consolidated material, remove alternate scarifier teeth. This will ease passage of the scarifier through the material.

CAUTION

Never make sharp turns with the scarifier teeth in the ground. Making sharp turns damages the scarifier and possibly bends or breaks the teeth.

During prestart operations, check the scarifier teeth for wear. When the caps are worn enough to cause damage to the shank, replace the cap (fig. 10-22).

Figure 10-24.-45-degree position of the blade.

Figure 10-25.-Ditch cut.