Maintenance - DeWalt DWS780LST Instruction Manual

into two pieces. Ensure the screws are tightened properly, otherwise material could loosen
and cause injury. Ensure the platform is firmly flat on the table, against the fence, and
centered evenly from left to right.
WARNING: Ensure the saw is mounted firmly to a stable flat surface. Failure to do so
could cause the saw to be unstable and fall causing personal injury.
4. Place the workpiece to be cut on top
of the platform mounted to the table.
Ensure the workpiece is firmly against
the back of the base fence (Fig. 25).
5. Secure the material before cutting.
Cut slowly through the material using
a out-down-and-back motion. Failure
to clamp securely or cut slowly could
result in the material coming loose
and causing injury.
After several cuts are made at various
miter angles other than 0º, the platform
may weaken and not properly support
the work. Install a new, unused platform
to the saw after presetting the desired
miter angle.
CAUTION: Continued use of a
platform with several kerfs may cause
loss of material control and possible injury.
Removing and Replacing Belt (Fig. 4, 26)
The belt is designed to last the life of the
tool. However, abuse of the tool could
cause the belt to fail.
If the blade does not turn when the motor
is running, the belt has failed. To inspect
or replace the belt, remove the belt cover
screws. Remove the belt cover. Inspect
the ribs of the belt for wear or failure.
Check belt tension by squeezing the belt as
shown in Figure 26. The belt halves should
almost touch when squeezing firmly with
the thumb and index finger. To adjust the
tension, loosen, but do not remove, the
four crosshead screws shown. Then rotate
the set screw on the top of the motor
plate casting until the proper tension is
achieved. Tighten the four screws securely
and replace the belt cover.
NOTICE: Overtightening the belt will cause
premature motor failure.

MAINTENANCE

WARNING: To reduce the risk of serious personal injury, turn off the tool and
disconnect it from the power source before attempting to move it, change
accessories or make any adjustments.
WARNING: To reduce the risk of serious personal injury, DO NOT touch the sharp
points on the blade with fingers or hands while performing any maintenance.
FIG. 25
BASE FENCE
FIG. 26 SCREW
SCREWS
DO NOT use lubricants or cleaners (particularly spray or aerosol) in the vicinity of the plastic
guard. The polycarbonate material used in the guard is subject to attack by certain chemicals.
• All bearings are sealed. They are lubricated for life and need no further maintenance.
• Periodically clean all dust and wood chips from around AND UNDER the base and the
rotary table. Even though slots are provided to allow debris to pass through, some dust
will accumulate.
• The brushes are designed to give you several years of use. If they ever need
replacement follow the instructions under Brushes or return the tool to the nearest
service center for repair.
Worklight Cleaning
For the best worklight performance, perform the following maintenance regularly.
• Carefully clean sawdust and debris from worklight lens with a cotton swab.
• DO NOT use solvents of any kind, they may damage the lens.
• Dust build-up can block the worklight and prevent it from accurately indicating the line of
cut.
• Follow miter saw's instruction manual to remove and install blade.
• With blade removed from saw, clean pitch and build-up from blade. Pitch and debris can
interfere with the worklight and prevent it from accurately indicating the line of cut.
Light source
Worklight
Power Supply
Operating Temperature 14°F to 104°F (-10°C to 40°C)
SET
Storage Temperature
Environmental
Dust Duct Cleaning
Depending on your cutting environment, saw dust can clog the dust duct and may prevent
dust from flowing away from the cutting area properly. With the saw unplugged and the saw
head raised fully, low pressure air or a large diameter dowel rod can be used to clear the dust
out of the dust duct.
Brushes
WARNING: To reduce the risk of serious personal injury, turn off the tool and
disconnect it from the power source before attempting to move it, change
accessories or make any adjustments.
Inspect carbon brushes regularly by unplugging tool, removing the motor endcap (Fig. 4),
lifting the brush spring and withdrawing the brush assembly. Keep brushes clean and sliding
freely in their guides. Always replace a used brush in the same orientation in the holder as it
was prior to its removal. If the brushes are worn down to approximately 1/2" (12.7 mm), the
springs will no longer exert pressure and they must be replaced. Use only identical D
brushes. Use of the correct grade of brush is essential for proper operation of electric brake.
New brush assemblies are available at D
to "run in" (run at no load) for 10 minutes before use to seat new brushes. The electric brake
may be erratic in operation until the brushes are properly seated (worn in). Always replace the
brush inspection cap after inspection or servicing the brushes.
While "running in" DO NOT TIE, TAPE, OR OTHER WISE LOCK THE TRIGGER SWITCH ON.
HOLD BY HAND ONLY.
14
SPECIFICATIONS
Power LED
3.3 V DC
Input: 120–240 V AC; 50/60Hz
Output: 5 V DC; 0.45 A
-22°F to 176°F (-30°C to 80°C)
Water resistant
WALT service centers. The tool should be allowed
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WALT
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