ing job is to be started, or when an extensive
thickness change is to be made on a job, the operator
can adjust the handwheels to the reference marks and
start-off very close to the mat thickness desired, if he
has recorded reference close to the new requirement.
Without a reference he must guess at the setting and
make corrections on the first several feet of the new
mat. Eventually an operator's reference record will
cover most of the common mat thicknesses and types
of material used
Change of material specifications will usually
cause a different screed behavior and a different
handwheel setting, even though the mat thickness is a
common one.
To obtain a smooth mat, the screed adjustment
controls should be gradually changed, one notch at a
time, and the screed should travel a few feet before
an additional adjustment is made. This will allow
the screed the proper distance of travel required to
seek the new level of operation.
Handwheels Set to Level Inclined Roadway
Figure 6
The scale is graduated vertically from a central
zero marking. The graduations may be in inches, with
increments of 1/4", 3" each way from the zero, so
that the total range is 6". Or the graduations may be
in turns of the handwheel, with increments of 1 turn,
12 turns each way from zero, so that the total range is
24 turns.
The disc-like gauge which is attached to the
handwheel screw has 12 equally space markings
which can be indexed from the edge of the vertical
scale to show the division of 1 turn.
The scale reading is taken by holding a small
straight edge upward against the bottom of the gauge
disc and across the scale face.
When an operator has established the best hand
wheel setting for paving a specific thickness with a
specific material, he will zero the two gauge and scale
readings then tighten the gauge setscrews. He then
Screed Man Making Handwheel Adjustment
makes a record of the conditions and gauge settings
Figure 8
for future reference. Whenever a new pav-
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