How To Install Crown Molding on a Cathedral/Vaulted Ceiling.
Chapter 5 of our new book covers cathedral/vaulted ceilings. We have provided many examples and photographs that will explain how you can easily install crown molding. There are three different ways you can make a turn with your crown. We have provided examples in Chapter 5 of when and how you should make each.
Take a close look at the above drawing.
• Joint "A" is a standard inside corner. The crown angle for joint "A" is 52 deg. (This is a horizontal turn of the crown molding)
• Measure the angle between the adjacent walls in the corner with your True Angle® Tool and, using the Crown Molding & Trim book, Compound Miter Chart, Crown Moulding Table or the Excel Program, determine the miter and blade tilt to cut the crown molding.
• You will always be able to see the saw cut and the pointed end will always be at the bottom of the crown molding.
• Cut the mating right-hand piece that will go in the corner. This is the crown moulding that goes from joint "A" to "B".
Now this is where it gets a little tricky.
note: The right end of the crown is the good piece. This is the short piece that goes from joint "A" to joint "B". (I am now cutting the left-hand side of joint "B")
• Use your True Angle® Tool and measure the angle between the wall and the ceiling, then add 90 degrees to it to get the actual corner angle for joint "B". (i.e. Our example is a 20-degree slope roof; therefore, the angle between the wall and the ceiling is 110 degrees. The corner angle for joint "B" is 110+90=200 deg.)
• The bottom of the crown is next to the fence and the top will be cut so it is
0 inches long (makes a point).
• Using 200 deg. as the corner angle and the crown slope angle of 38 deg. (use the complement angle of the crown for vertical turns, up or down), you can obtain the miter and blade tilt from the Compound Miter Chart, Crown Moulding Table or the Compound Miter Excel Program. (When you are turning the crown molding up or down, you have to use the complement angle of the crown moulding in the calculation to get the correct miter and blade tilt angles. The complement angle for this crown is 38 deg.) The Excel Program already compensates for the complement angle, therefore just input the 52 deg as asked for on the excel program page.
• Cut as shown using the above corner angle of 200 deg and crown angle of 38 deg.
• Joint "C" is an inside corner vertical turn down. Use your True Angle® Tool and measure the angle that both ceilings make with each other. In our example, that corner angle is 140 deg. and the crown angle is, of course, 38 deg. (The complement angle is used for vertical turns.) From the Compound Miter Chart, Crown Moulding Table or the Excel Program, you can obtain the correct miter and blade tilt for this joint. Continue around the room until completed.
That's all there is to it!