Here is a full tutorial, in case you haven't installed crown before.

Here is the angle generator for cutting crown in the flat position:

http://www.installcrown.com/Crown_angle_generator.html

For 52 / 38 crown put 38 as the spring angle, for 45 /45 crown put in 45. Notice the settings are different, most miter saws are set up for only one spring angle.

You may find your corners aren't a true 90 if they aren't cabinets so a protractor is usually needed as well.

Alter Eagle Construction & Design

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