Crown Molding question

[David Kenagy]

My 'built-in' cabinet goes into a room with a 'knee wall'. Two of the room's walls are vertical, and two slope down (parallel to the pitch of the house's roof) until a point 4' above the floor, where they also become vertical. The cabinet will have a flat face with crown molding, running in the usual (horizontal) direction. It meets those end walls 75" above the floor, but the ceiling is at 96". between those two heights, we still have "wall" or "sloped ceiling" at a 36 degree angle (a "9 over 12" pitch). Crown molding on those end walls will be horizontal at the main ceiling, then slope down toward the cabinet.

How do I cut (or cope) the connections between the cabinet crown and the wall crown? My "bail out" plan will be to make rectangular blocks at the corners, which would mean simple 90 degree ends to the horizontal molding, and 36 degree angled cuts for both ends of the sloped part.

[Tom M King]

If you want them to mesh perfectly, one of the crowns is going to need to be custom made. The same size of crowns for all of it just won't work. I think it's about 33 degrees that 3-5/8" crown, and 4-5/8" crown come close to working, but this is off of years old memory. Google "custom raking cyma", and it should show up how it's done. The block in the corner will be the easy way.

edited to add: Funny. I checked my suggested Google search, and a picture from my website showed up, with all the other stuff. That picture was the 3-5/8's, and 4-5/8's being used to avoid making a custom piece.