There are three ways of cutting crown molding.
Some times the miter angle or saw blade bevel angle is beyond the capabilities of the compound miter saw. Or it's just easier to cut the material on edge instead of laying flat in the compound miter saw.
Example of cutting the tetrahedron platonic solid.
Settings for Cutting the Material Laying Flat in the Compound Miter Saw
Saw Miter Angle = 54.7356°
Saw Blade Bevel Angle = 30.0000°
Settings for Cutting the Material On Edge in the Compound Miter Saw
Top Edge of Hip Rafter Saw Miter Angle = 45.000°
Top Edge of Hip Rafter Saw Blade Bevel Angle = 45.00°
|The tetrahedron platonic solid material is cut on edge.|
You can use this calculator to cut any type of material . It is not limited to crown molding on edge. I use it all the time to cut purlin rafters, the compound joinery of the platonic solids and the compound joinery of Archimedean Solids.