My first two posts were lost, so this will be short and sweet.
From what I can tell, you’re installing a rather complex profile of crown molding, which is much more difficult than some would imagine. Whatever it is, however, the return is vital to making it look acceptable. It’s a mark of craftsmanship. Don’t skip doing it.
First, accept the fact that most of the experts out there in the real world don’t know what the heck they’re talking about–and I’m including lots of production carpenters and the boys over at Home Depot and Lowe’s. These guys usually get by with lots of caulk and bad lighting. The more I learn about woodworking and carpentry–I’ve got a lot of time on my hands and a big house and barn–the more I realize that these Professional BS’ers know next to nothing. (End of rant.)
Second, make sure you acclimate the wood properly. Bring it into your house and let it sit there a good couple of months. Many people neglect this step, but when the wood later shrinks and your lapped joints and mitered/coped corners open up, the results will be disappointing. And make sure to spring the longer pieces.
Third, make sure you’re using a power miter saw. I’ve got a very fancy compound miter saw, but I’ve found that cutting my crown standing up allows for more accurate fine tuning than laying it flat. And forget about a miter box and back saw. The results are bad and it’s a royal pain in the butt.
Fourth, build yourself a jig. I can’t explain how over the Net, but check back issues of Family Handyman. Jigs make for easier work. Ever notice what a pain it is to work with 16-foot lengths?
Fifth, accept the fact that getting good at finish carpentry–especially crown molding, the king of moldings AND the king of headaches–takes time. If you want to speed the learning curve, get a quality craftsman to give you a lesson or two.
Last, take notes as you go and build a few sample pieces with the settings on them.
As for the end/returns/caps, they are mirror images of the longer pieces. I cannot explain how to do it over the NET–and have it make sense to you–just play around and you will get it. Make sure to make notes as you go.