This is a Larry Brand design that I assembled from parts contained in a LOC Precision Lil Nuke kit and an extra length of 54mm tubing.  LOC 54 mm tubing is motor mount grade so it's a bit thicker than most.  I also ordered a 6" long payload bay kit to complete the build.

Larry's article on the original Auracle 54 is sketchy on details and so I relied on the photgraphs accompanying the article.  When all was said and done, I'm happy with the way it turned out.  In retrospect, I will never again attempt a tube fin with tapered ends.