DeWalt DHS780 Original Instructions Manual page 17

Your saw has a built-in dust port that allows you to connect the supplied dust bag or a
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shop vacuum system using either the AirLock™ system (DWV9000-XJ) or a standard 35 mm
dust extractor fitment.

WARNING: ALWAYS use a vacuum extractor designed in compliance with the applicable
directives regardig dust emission when sawing wood. Vacuum hoses of most common
vacuum cleaners will fit directly into the dust extraction port.
To Attach the Dust Bag
1. Fit the dust bag to the dust port ..
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To Empty the Dust Bag
1. Remove dust bag from the saw and gently shake or tap the dust bag to empty.
2. Reattach the dust bag back onto the dust port
You may notice that all the dust will not come free from the bag. This will not affect cutting
performance but will reduce the saw's dust collection efficiency. To restore your saw's dust
collection efficiency, depress the spring inside the dust bag when you are emptying it and tap
it on the side of the trash can or dust receptacle.

CAUTION: Never operate this saw unless the dust bag or D
in place. Wood dust may create a breathing hazard.
Basic Saw Cuts
If the slide feature is not used, ensure the saw head is pushed back as far as possible and the
rail lock knob 24 is tightened. This will prevent the saw from sliding along its rails as the
workpiece is engaged.
Cutting of multiple pieces is not recommended but can be done safely by ensuring that each
piece is held firmly against the table and fence.
Straight Vertical Crosscut (Fig. A)
1. Set and lock the mitre arm at zero, and hold the wood firmly on the table and against the
fence 16 .
2. With the rail lock knob 24 tightened, turn on the saw by squeezing the trigger switch
3. When the saw comes up to speed, lower the arm smoothly and slowly to cut through the
wood. Let the blade come to a full stop before raising arm.
Sliding Crosscut (Fig. A, O)
When cutting anything larger than a 51 x 150 mm (51 x 105 mm at 45° mitre) workpiece, use
an out-down-back motion with the rail lock knob
1. Pull the saw out toward you.
2. Lower the saw head down toward the workpiece.
3. Slowly push the saw back to complete the cut.
Do not allow the saw to contact the top of the workpiece while pulling out. The saw may run
toward you, possibly causing personal injury or damage to the workpiece.
Mitre Crosscut (Fig. P)
The mitre angle is often 45° for making corners, but can be set anywhere from zero to 50° left
or 60° right. Proceed as for a straight vertical crosscut.
When performing a mitre cut on workpieces wider than 51 x 105 mm that are shorter in
length, always place the longer side against the fence.
Bevel Cut (Fig. A, Y2)
Bevel angles can be set from 49° right to 49° left and can be cut with the mitre arm set
between 50° left or 60° right. Refer to the Features and Controls section for detailed
instructions on the bevel system.
1. Loosen the bevel lock knob 28 , and move the saw to the left or right as desired. It is
necessary to move the fence 16 to allow clearance. Tighten the fence adjustment
knob 63 after positioning the fences.
2. Tighten the bevel lock firmly.
At some extreme angles, the right or left side fence might have to be removed. Refer to Fence
Adjustment in the Adjustments section for important information on adjusting the fences
for certain bevel cuts.
To remove the left or right fence, unscrew the fence adjustment knob
slide the fence out.
Grooving (Fig. A)
Your saw is equipped with a grooving stop
nut 33 to allow for groove cutting.
• Flip the grooving stop 35 towards the front of the saw.
• Adjust the wing nut and depth adjustment screw
33
groove cut.
Quality of Cut
The smoothness of any cut depends on a number of variables, such as the material being cut,
blade type, blade sharpness and rate of cut.
When smoothest cuts are desired for molding and other precision work, a sharp (60 tooth
carbide) blade and a slower, even cutting rate will produce the desired results.

WARNING: Ensure that the material does not move or creep while cutting; clamp it
securely in place. Always let the blade come to a full stop before raising arm. If small
fibers of wood still split out at the rear of the workpiece, stick a piece of masking tape on
the wood where the cut will be made. Saw through the tape and carefully remove tape
when finished.
Clamping the Workpiece

WARNING: A workpiece that is clamped, balanced and secure before a cut may become
unbalanced after a cut is completed. An unbalanced load may tip the saw or anything the
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WALT dust extractor is
e
24 loosened.
63 several turns and
35 , depth adjustment screw 34 and wing
to set the depth of the
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saw is attached to, such as a table or workbench. When making a cut that may become
unbalanced, properly support the workpiece and ensure the saw is firmly bolted to a
stable surface. Personal injury may occur.

WARNING: The clamp foot must remain clamped above the base of the saw whenever
the clamp is used. Always clamp the workpiece to the base of the saw – not to any other
part of the work area. Ensure the clamp foot is not clamped on the edge of the base of
the saw.

CAUTION: Always use a work clamp to maintain control and reduce the risk of personal
injury and workpiece damage.
Use the material clamp provided with your saw. The left or right fence will slide from side to
side to aid in clamping. Other aids such as spring clamps, bar clamps or C-clamps may be
appropriate for certain sizes and shapes of material.
To Install Clamp
1. Insert it into the hole 29 behind the fence. The clamp should be facing toward the back of
the mitre saw. The groove on the clamp rod should be fully inserted into the base. Ensure
this groove is fully inserted into the base of the mitre saw. If the groove is visible, the
clamp will not be secure.
2. Rotate the clamp 180° toward the front of the mitre saw.
3. Loosen the knob to adjust the clamp up or down, then use the fine adjust knob to firmly
clamp the workpiece.
nOTE: Place the clamp on the opposite side of the base when beveling. ALWAYS MAKE DRY
RUNS (UNPOWERED) BEFORE FINISH CUTS TO CHECK THE PATH OF THE BLADE. ENSURE THE
CLAMP DOES NOT INTERFERE WITH THE ACTION OF THE SAW OR GUARDS.
Support for Long Pieces
ALWAYS SUPPORT LONG PIECES.
For best results, use the DE7023-XJ or DE7033-XJ leg stands to extend the table width of
your saw. Support long workpieces using any convenient means such as sawhorses or similar
5 .
devices to keep the ends from dropping.
Cutting Picture Frames, Shadow Boxes and Other Four-Sided
Projects (Fig. R)
Try a few simple projects using scrap wood until you develop a "feel" for your saw. Your saw is
the perfect tool for mitring corners like the one shown in Figure R.
Sketch 1 in Figure R shows a joint made with the bevel adjustment method. The joint shown
can be made using either method.
• Using bevel adjustment:
- The bevel for the two boards is adjusted to 45° each, producing a 90° corner.
- The mitre arm is locked in the zero position and the bevel adjustment is locked at 45°.
The wood is positioned with the broad flat side against the table and the narrow edge
-
against the fence.
• Using mitre adjustment:
- The same cut can be made by mitring right and left with the broad surface against
the fence.
Cutting Trim Molding and Other Frames (Fig. R)
Sketch 2 in Figure R shows a joint made by setting the mitre arm at 45° to mitre the two
boards to form a 90° corner. To make this type of joint, set the bevel adjustment to zero and
the mitre arm to 45°. Once again, position the wood with the broad flat side on the table and
the narrow edge against the fence.
The two sketches in Figure R are for four-sided objects only. As the number of sides changes,
so do the mitre and bevel angles. The chart below gives the proper angles for a variety of
shapes, assuming that all sides are of equal length.
Number of Sides
4
5
6
7
8
9
10
For a shape that is not shown in the chart, use the following formula: 180° divided by the
number of sides equals the mitre (if the material is cut vertically) or bevel angle (if the material
is cut laying flat).
Cutting Compound Mitres (Fig. Q, R, S, Z)
A compound mitre is a cut made using a mitre angle and a bevel angle at the same time.
This is the type of cut used to make frames or boxes with slanting sides like the one shown in
Figure Q.

WARNING: If the cutting angle varies from cut to cut, check that the bevel lock knob and
the mitre lock handle are securely locked. These must be locked after making any changes
in bevel or mitre.

WARNING: The saw must be fixed on a base support when performing compound cuts to
prevent tip over. Refer to Bench Mounting and Fig. Z.
The chart shown below will assist you in selecting the proper bevel and mitre settings for
common compound mitre cuts.
EngliSH
Mitre or Bevel Angle
45°
36°
30°
25.7°
22.5°
20°
18°
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