I am the cad designer at Harper College and work with graphics and Autocad.
I was also an scale boat modeler (years ago) and dreamed of being able to scale model plans into a larger model. With today's technology it's easier than you can imagine. Most blueprint reproduction companies are using KIPP machines that scan 36" wide prints and turn them into TIFF's or bitmaps at a resolution of 400 dpi for about $1.50 a page. Large files...but great price. These images (tiffs) are imported into Autocad as a raster image. Dimension and scale the image until you are happy with say... the length of the wingspan.... and everything on the SAME page is scaled exact. For multi-page prints it will be necessary to have an associated dimension that will transfer from page to page. This could be anything from a section view or profile, just as long as all the pages are scaled the same. Full scale plans are only limited by the size of your plotter. Most are 36" wide and handle 80-150' rolls of paper. Imagination will allow you to scale up to full size aircraft.. forgive me if I refuse to fly in it. With 3d you can study the aircraft on the screen before you actually build it. Hoped I helped some.
Now that I've donated something and will help further if asked..... Does anyone have or know where to get a FULL set of plans for a cnc router table with XYZ axis's. By full I mean servo control wiring and where to connect the red wire to.