Crown where ceiling is 45 deg to the wall

[Monju123]

I am crowning my den. Most is routine molding, but one vaulted section has walls that meet the ceiling at 45 deg instead of 90. As a result, the molding is not flush with the ceiling. How do I handle this?

 

[Brice Burrell]

Here's a link Nick posted a while back, scroll down to figure 10.

 

[Loren Woirhaye]

I think perhaps you want to know how to support the moulding when
there is no ceiling to nail it to.  Just built a base for that section
out of plywood scrap in a triangular shape.  This is necessary
with some built-up moulding installations anyway.