gives the material that has been brought forward a
chance to fall out the apron opening.
NOTE: When the material is spread too thin or the
bowl is too low, the material will pack against the
scraper cutting edge inside the bowl and will not eject.
Loose Sand and Gravel
Sand is a free-flowing material that tends to float
ahead of the scraper cutting edges when being loaded.
To obtain a heap scraper load when loading and to avoid
being bogged down by the sand, use the technique called
pump loading. To pump load, enter the cut with the
apron open about 3 feet and the scraper cutting edges
lowered into the sand. Continue through the cut until
the engine(s) starts to lug down. Then lower the apron
into the sand that has piled up in front of the scraper
cutting edges, and raise the bowl 2 or 3 inches at a time.
Do not completely close the apron or drop the bowl so
deep that the engine stalls. This pump loading
technique will ordinarily allow the scraper to get a full
When spreading sand, always spread it as thin as
possible, and keep the scraper moving in the fill. A thin
spread allows better compaction and makes it easier to
travel over the fall.
To obtain a full load when loading gravel, you may
have to pump load as performed with sand. The apron
may be hard to close due to stones getting caught
between the apron and cutting edges. A technique used
to avoid the stones is to backup a few inches with the
blade still in the ground while closing the apron. This
should force the stones out and allow the apron to close
all the way.
Scrapers are not designed to dig or transport large
objects; however, they may be used for this purpose
when more suitable equipment is not available.
Approach the object with the apron and scraper
bowl fully raised. When the object is too large to clear
underneath the tractor, bring the tractor past the object
until the drive wheels are a few inches beyond it. Pivot
the tractor sharply towards the object to allow the tractor
to bypass the object, and bring the cutting edge into
position for loading (fig. 10-43).
When the tractor reaches its sharpest angle of the
turn, bring the scraper cutting edges within a few inches
of the object. Lower the bowl, apply down pressure, and
When the cutting edge hooks
underneath the object, lift the bowl while inching
forward. When the object slips off the cutting edge,
back up and try again. You may have to approach the
object from a different direction to get a grip to load the
To shove the object around, keep the ejector in the
full forward position. When the object is to be picked
up and carried, place the ejector in the normal fullback
position. To close the apron completely after the object
Figure 10-43.-Scraper maneuver to load large object.