This is my entry for the $75 Build Contest and my scheme is to take the Titan toy glider "build-over" plug and construct a variation of the XP-55 Ascender. I have a small collection of Titan glider toy RC conversion pictures collected off the internet and pictures of XP-55 Ascender look alikes. Most of the look alikes are art, but some are models made from plastic, wood, or foam. If I look about for a bit, I can probably find some paper scale models and more fantasy aircraft models, or art. There are computer games like Crimson Skies by MS that took aircraft from the 1920-1950's with various changes and made them into aircraft for air pirates. Some of the changes made it difficult to figure out which aircraft the variant was modeled from. Many of the models were based on experimental aircraft designs.
My plan is to do the same sort of thing, but it may not be so hard to figure out the aircraft my variant is modeled from. What is different is the use of a build-over plug made from a Titan glider toy fuselage. I got the idea, generally speaking, after watching a master modeler of free flight models use a foam plug to help shape thin strips of balsa wood he had covered in wood glue. The balsa wood strips were very, very thin and once wetted with the slightly thinned wood glue, they would bend around the foam plug. He would wrap the strips around the foam plug at least three times to make a laminated rib. Later he would add strips of wood between the laminated ribs to capture the shape of the foam plug. He ended up with a strong, lightweight balsa wood "bird cage" he could cover in tissue paper.
The balsa wood "bird cage" was cut in half so the foam plug could be removed, glued back together, and covered in tissue paper to make the free flight model that was rubber band powered. I am doing the same sort of thing, but instead of balsa wood, I am using rings from recycled foam drinking cups. I also use the $1 foam sheets from the poster board sold by the Dollar Tree store (paper removed). Since I can buy fan fold foam (Blu-core and other options) for less than $1 a sheet from time to time, I use it when a thicker, softer foam board offers an advantage. When making foam fuselage or wing ribs, I find the foam drinking cup material superior to other options. The building process is a little different in some ways, but generally still very old school with ribs and stringers covered with sheeting, but in this case the skin of the fuselage, or wing is thin foam board, rather than balsa, or thin plywood.
Hopefully I have described the basic details enough and others might see the advantages to the process. The basic detail to notice is foam drink cups are about as free a source of building material as one can get. Most are used once and thrown away. I have been keeping mine for a while now and have the family members give me theirs when they are done with them. I did a little dumpster diving, or trash picking at first, but ended up with so many in a large cardboard box within a month, I stopped, and have only collected from the family to keep my surplus supplies peaked. At first I only collected the largest foam cups, but have since collected all sizes available. The smaller the foam cup, the thinner the foam, and the more flexible. A useful set of characteristics for the tail area of a fuselage, or wing tip. One exception to flexible foam cup is the thin foam coffee cups. They are very stiff, and useful when you want to stiffen a rib, or skin area. Enough for now.