Cutting Compound Miters - Black & Decker BT1400 Instruction Manual

To make this type of joint, set the miter arm to 45º degrees. The wood was positioned with the broad
flat side against the table and the narrow edge against the fence.
• As the number of sides changes, so do the miter angles. The chart below gives the proper angles for
a variety of shapes. (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 degrees divided by the
number of sides equals the miter.

CUTTING COMPOUND MITERS

The 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 Fig. H.
NOTE: If the cutting angle varies from cut to cut, check that the bevel clamp knob (10) and the miter
clamp handle (4) are securely tightened. These knobs must be tightened after making any changes in
bevel or miter.
CUTTING CROWN MOLDING
• In order to fit properly, crown molding must be 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 degrees.
Most, but not all, crown molding has a top rear angle (the section that fits flat against the ceiling) of
52º degrees and a bottom rear angle (the part that fits flat against the wall) of 38º degrees.
• Pretesting with scrap material is extremely important! Place the bottom side (the side that will be
against the wall) against the miter saw fence. Place the top (that part that will be against the
ceiling) against the saw table and the crown molding fence.
Instructions for cutting crown molding angled between the fence and the table of the saw for all cuts:
• Angle the molding so the bottom of the molding (part which goes against the wall when installed) is
against the fence and the top of the molding is resting on the table of the saw.
• The angled "flats" on the back of the molding must rest squarely on the fence and table of the saw.
INSIDE CORNER:
Left side
• Miter right at 45°
• Save the right side of cut
OUTSIDE CORNER:
Left side
• Miter left at 45°
• Save the right side of cut
Always make dry runs to check for clearance and correctness of cuts.
NEVER MAKE ANY CUTS UNLESS THE MATERIAL IS SECURED ON THE TABLE AND AGAINST THE FENCE.
EXAMPLES
NO. SIDES ANGLE MITER
4
5
6
7 25.7º
8 22.5º
9
10
Right side
• Miter left at 45°
• Save left side of cut
Right side
• Miter right at 45°
• Save left side of cut
35
45º
36º
30º
20º
18º
ENGLISH