Paneling and Trim - Mitre Cut for Chair Rail

I am having a difficult time figuring out how to connect two chair rail lengths at this intersection in my wainscott. I am having a tough time trying to find how to mitre cut the ends of the contoured rail to make a smooth transition.

http://img524.imageshack.us/img524/6409/chairail.th.jpg (http://img524.imageshack.us/i/chairail.jpg/)

Referring to the picture ....

Am I to assume that the cut I need to make is represented by the red line A-B?

And if so, how do I accurately find the angle, and cut my stock to ensure the proper angle ABC. Not being a mathmetician, will angle ABC be the same as angle ABD?

Any help will be greatly appreciated. I have a compound mitre saw, but have tried to logically guess at the cut angle to match perfectly. I have failed obviously.

Jenn

Angles ABC and ABD may not be the same, BUT your cut on the molding must be the same angle. If you can figure the angle of CBD, then divide in half, cut the molding it will fit. If you try to cut different angles, the lengths of the angular wood will be short and long and it won't look right.

Place the moulding on a piece of flat stock so that the back side will be parallel to the saw table, otherwise the lip on the back will cause problems when you make the cut. Make trial cuts using two pieces of scrap until you are satisfied with the fit where the two pieces join at the angle; then cut the moulding. Good luck with your project.

OK. Awesome! With your guidance guys I figured that one one with a bit of trial and error.
I measured the angle and set the mitre saw at half that angle. I ended up having to add several degrees on the saw before the joint lined up. (62.5 degrees to 77 degrees.)

Now that the simple cut has been figured out, I found myself in an even worse predicament.

Scenario ... outside corner, horizontal to diagonal. Yikes!
I'm turning to the pros again to help me understand the best plan of attack. A simple outside corner is OK. And you have taught me to do an odd angled simple plain angle joint, but now I'm working on two different plains. :wall:

http://img143.imageshack.us/img143/7167/1001488.th.jpg (http://img143.imageshack.us/i/1001488.jpg/)

Jenn

What you have to do is make the angle piece turn to 90 degrees to the horizontal one. Cut back similarly to the way you did on the other one, dividing the angle in half so it turns horizontal. Then a standard 90 degree outside corner would work.

Thank you Chandler ...
Will have to think about that one for a while, play around, see if I can apply your logic.
I'll be sure to report back with my success and of course appreciation.