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.
for
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
wear. When the caps are worn enough to cause
damage to the shank, replace the cap (fig. 10-22).
Figure 10-22.—Scarifier tooth.
Figure 10-24.—45-degree position of the blade.
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