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 made.

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°. Most crown 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 40.

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 moldings 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.

When cutting crown molding by this method the bevel angle should be set at 33.85°. The miter angle should be set at 31.62° 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 on page 29 can be used for cutting All Standard (U.S.) crown molding with 52° and 38° angles. The crown molding is placed flat on the miter table using the compound features of your miter saw.

38°

W

A

L

L

52°CEILING

FENCE

TOP EDGE AGAINST FENCE =

LEFT SIDE, INSIDE CORNER

RIGHT SIDE, OUTSIDE CORNER

MITER TABLE

INSIDE

CORNER

FENCE

OUTSIDE

CORNER

 

BOTTOM EDGE AGAINST FENCE =

RIGHT SIDE, INSIDE CORNER

LEFT SIDE, OUTSIDE CORNER

MITER TABLE

CROWN MOLDING FLAT ON MITER TABLE

Fig. 40

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Image 28
Ryobi P550 manual Cutting Crown Molding, Laying Molding Flat on the Miter Table