TM 5-3895-359-14&P
forward speed should vary accordingly. The rotor depth
turn around. The mixer is then worked back
control caps should always ride tight on top of the hood
into the section and the material "feathered
reinforcing ribs.
out" as described earlier.
8. By using the tailboard lever, adjust tailboard opening
so that an even flow of material results. The proper
retention of material in the mixing chamber controls the
buildup and spill-over. This affects the extent of mixing,
blending and pulverization.
To further simplify on the preceding procedure and to
add to the mixing operation the following information is
detailed:
a. At the job site, the material for mixing should be
either scarified (loosened), bladed or in windrows,
where applicable.
b. Drive onto the lane to be mixed with the hood
Figure 1-10. Rotor Operation
and rotor assembly raised. When in position to start
mixing operation with engine at 2000 rpm and at
normal operating temperatures, rotor at low speed,
e. This procedure will leave a finished surface that
slowly move forward-reverse lever forward,
will roll out smooth and level. A very important
increasing speed. As machine moves forward,
function of the machine known as the diagonal cross
lower the rotor and hood assembly to full adjusted
mix can be effectively incorporated into the process
mixing depth. Travel and mix as outlined in steps 5
after the admixture pass. This "cross-blending"
thru 8.
action serves to mix the materials and to blend out
any variations in materials, minor grade and crown.
c. To finish a run where the end joins a previous
Any road will normally require two cross mixing
section, operate the mixer right up to the section
passes and then straight passes to cover the full
end, decrease speed, depress rotor clutch, raise
width. The diagonal pass is accomplished by simply
rotor and hood assembly. This procedure will leave
driving the machine in long, easy curves, crossing
a pile of material at the end. This pile can be
the work at a shallow angle of not more than 300
carried back by straddling it on the return trip. Work
from straight ahead' position. DO NOT "swing" the
it back or feather it out. Following this procedure
machine too short and cause the rear unit to spread
will prevent the movement of materials away from
and overlap the outer edges. Long, easy turns work
the end or joint. Avoid successive starts on the
out the best, starting from the outer edge of the
same spot without having first deposited a spill-over
work.
pile from the previous run. (Too much material
moved from one spot, will of course, change the
f. Regulating the tailboard opening will control the
grade and also result in a "leaning out" of the
spill-over (or the amount of material carried forward
mixture by constantly exposing new base material.)
within the hood for remixing). The tighter the
In the event that the mixing unit is raised too rapidly
tailboard opening, the better the mixing and
and a ridge is left, raise rotor, back up and lower the
blending; however, the forward mixing speed, depth
mixing unit onto this ridge and work the mixer
of cut, type of material and engine power are all
through it and then proceed to "feather out" again.
factors that dictate how tight the tailboard should be.
Then the mixer unit can be raised all the way and
This must be determined for each individual job.
the machine moved to the next location.
g. On "slippery" or "tender" material where traction
NOTE: One of the most important functions
can become a problem and wheel slippage occurs,
contributing to the efficiency of the mixing
the crane should be raised slightly compressing the
characteristics of the mixer is the "spill-over"
traction spring, thereby effecting a weight transfer to
mentioned in the previous paragraph. This
the rear drive axle and increasing tractive effort. As
"spill-over" material will show up at the end of
long as the rotor depth control caps remain resting
a section when the mixer is stopped and the
on the hood reinforcing ribs, the depth of the cut will
mixing unit is raised for a turn-around. These
not be affected.
steps should be followed to achieve the
smooth finish results possible. (Fig. 1-10) d.
h. When processing rocky or "bony" material where
Work mixer right up to the end of the section
severe shock can be transmitted to the machine,
and stop the unit abruptly. Raise rotor into
reduce the engine rpm to 1200-1400 rpm. This
hood with the hood remaining on the ground.
reduces the rotor rpm, proportionally and makes for
Slowly move the machine forward, thereby
a much smoother operation without sacrificing any
dragging the spill-over material into the
mixing ability.
trench left by the rotor. Stop working and
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