DeWalt DHS790 Guide D'utilisation page 15

Fig. Z
Cutting Trim Molding And Other Frames (Fig. AA)
Sketch 2 in Figure AA shows a joint made by setting the miter arm at 45º to miter the two boards
to form a 90º corner. To make this type of joint, set the bevel adjustment to zero and the miter
arm to 45º. 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 AA are for four-sided objects only.
As the number of sides changes, so do the miter and bevel angles. The chart below gives the
proper angles for a variety of shapes.
– EXAMPLES –
NUMBER OF SIDES
4
5
6
7
8
9
10
The chart assumes that all sides are of equal length. For a shape that is not shown in the chart,
use the following formula: 180º divided by the number of sides equals the miter (if the material is
cut vertically) or bevel angle (if the material is cut laying flat).
Cutting Compound Miters (Fig. BB)
A compound miter is a cut made using a miter 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 BB.
nOTE: If the cutting angle varies from cut to cut, check that the bevel lock knob and the miter
lock handle are securely locked. These must be locked after making any changes in bevel
or miter.
The chart at the end of this manual (Table 1) will assist you in selecting the proper bevel and
miter settings for common compound miter cuts. To use the chart, select the desired angle A
(Fig. BB) of your project and locate that angle on the appropriate arc in the chart. From that point
follow the chart straight down to find the correct bevel angle and straight across to find the
correct miter angle.
Fig. BB
Set your saw to the prescribed angles and make a few trial cuts. Practice fitting the cut pieces
together until you develop a feel for this procedure and feel comfortable with it.
Example: To make a 4-sided box with 26º exterior angles (Angle A, Fig. BB), use the upper right
arc. Find 26° on the arc scale. Follow the horizontal intersecting line to either side to get miter
angle setting on saw (42°). Likewise, follow the vertical intersecting line to the top or bottom to
get the bevel angle setting on the saw (18°). Always try cuts on a few scrap pieces of wood to
verify the settings on the saw.
Cutting Base Molding (Fig. K, CC)
ALWAYS MAKE A DRY RUN WITHOUT POWER BEFORE MAKING ANY CUTS.
Straight 90º cuts:
Position the wood against the fence and hold it in place as shown in Figure CC. Turn on the saw,
allow the blade to reach full speed and lower the arm smoothly through the cut.
Cutting Base Molding from 3" UP TO 6.75" (76 mm to 171 mm) high Vertically Against
the Fence
nOTE: Use the slide lock lever 43 , shown in Figure K, when cutting base molding measuring
from 3" to 6.75" (76 mm to 171 mm) high vertically against the fence.
Position material as shown in Figure CC.
Fig. AA
1
2
1
MITER OR BEVEL ANGLE
45°
36°
30°
25.7°
22.5°
20°
18°
Angle "A"
Fig. CC
All cuts should be made with the back of the molding against the fence and with the bottom of
the molding against the table.
INSIDE CORNER
Miter left 45°
Left side
Save left side of cut
Miter right 45°
Right side
Save right side of cut
Material up to 6.75" (171 mm) can be cut as described above.
Cutting Crown Molding
Your miter saw is well suited to the task of cutting crown molding. In order to fit properly, crown
molding must be compound mitered with extreme accuracy.
The two flat surfaces on a given piece of crown molding are at angles that, when added together,
equal exactly 90º. Most, but not all, crown molding has a top rear angle (the section that fits flat
against the ceiling) of 52º and a bottom rear angle (the part that fits flat against the wall) of 38º.
Your miter saw has special pre-set miter latch points at 31.62º left and right for cutting crown
molding at the proper angle and bevel stop pawls at 33.9º left and right. There is also a mark on
the bevel scale at 33.9º.
The chart below gives the proper settings for cutting crown molding. (The numbers for the miter
and bevel settings are very precise and are not easy to accurately set on your saw.) Since most
rooms do not have angles of precisely 90º, you will have to fine tune your settings anyway.
PRETESTING WITH SCRAP MATERIAL IS EXTREMELY IMPORTANT!
Instructions for Cutting Crown Molding Laying Flat and Using
the Compound Features (Fig. DD)
1. Molding should lay flat with broad back surface down on saw table.
2. Top of molding against fence.
3. The settings below are for all standard (U.S.) crown molding with 52° and 38° angles.
INSIDE CORNER
Bevel left 33.9°
Left side Miter table set at right 31.62°
Save left end of cut
Bevel right 33.9°
Right side Miter table set at left 31.62°
Save right end of cut
When setting bevel and miter angles for all compound miters, remember that:
The angles presented for crown moldings are very precise and difficult to set exactly. Since they
can easily shift slightly and very few rooms have exactly square corners, all settings should be
tested on scrap molding.
English
OUTSIDE CORNER
Miter right 45°
Save left side of cut
Miter left 45°
Save right side of cut
OUTSIDE CORNER
Bevel right 33.9°
Miter table set at left 31.62°
Save left end of cut
Bevel left 33.9°
Miter table set at right 31.62°
Save right end of cut
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