I have worked out most of the problems on my 3D printer and successfully printed a large, reasonably complicated part. It is a custom fixture for a hex copter. Here is a video of part of the build process.
Here are some pictures of the finished product.
I have since installed a better webcam to take periodic pictures. I am using Yawcam to post the images through FTP to my web site.
And here is the quality of picture I can now capture.
The edges of the part are lifting off of the heated bed. I plan to try an ABS-acetone slurry to keep the part stuck down. Ever since I made the two halved, aluminum plate print bed cover, I can reuse my Kapton tape several times. If I use fresh tape and clean it with Acetone, adhesion also improves.