RIDGID R4221 Operator's Manual page 35

OPERATION
CUTTING CROWN MOLDING
The compound miter saw does an excellent job of cutting
crown molding. In general, compound miter saws do a better
job of cutting crown molding than any other tool.
In order to fit properly, crown molding must be compound
mitered with extreme accuracy.
The two contact surfaces on a piece of crown molding that
fit flat against the ceiling and the wall of a room are at angles
that, when added together, equal exactly 90
molding has a top rear angle (the section that fits flat against
°
the ceiling) of 52 and a bottom rear angle (the section that
fits flat against the wall) of 38
LAYING MOLDING FLAT ON THE MITER
TABLE
See Figure 48.
To use this method for accurately cutting crown molding for
a 90 ° inside or outside corner, lay the molding with its broad
back surface flat on the miter table and against the fence.
When setting the bevel and miter angles for compound
miters, remember that the settings are interdependent;
changing one angle changes the other angle as well.
Keep in mind that the angles for crown molding are very
precise and difficult to set. Since it is very easy for these
angles to shift, all settings should first be tested on scrap
molding. Also most walls do not have angles of exactly 90
therefore, you will need to fine tune your settings.
52
°
CEILING
38
°
W
A
L
L
°
. Most crown
° .
FENCE
TOP EDGE AGAINST FENCE =
LEFT SIDE, INSIDE CORNER
RIGHT SIDE, OUTSIDE CORNER
MITER TABLE
CROWN MOLDING FLAT ON MITER TABLE
When cutting crown molding by this method, the bevel angle
should be set at 33.85
31.6 ° either right or left, depending on the desired cut for the
application. See the chart below for correct angle settings
and correct positioning of crown molding on miter table.
The settings in the chart below can be used for cutting All
Standard (U.S.) crown molding with 52
crown molding is placed flat on the miter table using the
compound features of your miter saw.
Bevel
Angle
Setting
Left side, inside corner
1. Top edge of molding against fence
°
33.85
2. Miter table set right 31.62
3. Save left end of cut
Right side, inside corner
1. Bottom edge of molding against fence
33.85 °
2. Miter table set left 31.62
3. Save left end of cut
Left side, outside corner
1. Bottom edge of molding against fence
33.85 °
2. Miter table set left 31.62
3. Save right end of cut
° ;
Right side, outside corner
1. Top edge of molding against fence
°
33.85
2. Miter table set right 31.62
3. Save right end of cut
INSIDE
CORNER
35 - English
°
. The miter angle should be set at
° and 38
Type of Cut
OUTSIDE CORNER
FENCE
BOTTOM EDGE AGAINST FENCE =
RIGHT SIDE, INSIDE CORNER
LEFT SIDE, OUTSIDE CORNER
MITER TABLE
° angles. The
°
°
°
°
Fig. 48