This seemed like the best bet. As we have been experimenting with blowing large plastic bubbles, I decided to make my nosecone out of Vivak. I used a 2'x4' section to make my bubble. See the How to make blown HPV fairings page for more information. Once everything is in place, and the oven is up to the proper temperature.
Air pressure is applied behind the flat sheet of plastic, and it balloons outward.
I used two for this project. Basic Construction technique involves cutting the Coroplast with a knife, and then attaching the separate Coroplast parts with plastic wire ties. Support bracketry and reinforcements are attached with pop-rivets. The Vivak nosecone is attached to the Coroplast body with pop rivets. See Russel Dwarshuis Coroplast fairing page for info on building Coroplast nosecones.