The legs are made from a combination of foam core and 110 lb. card stock, along with pieces of cardboard tubing.
I am kind of a hoarder with any kind of cardboard tube, so I had a big pile to choose from for this project. However, I still had to make custom cardboard sleeves to fit over these existing cardboard tubes, to use as connectors for all the pieces of the body. To make these cardboard sleeves I used the same technique I have shown here
in my Bullet Bill Rocket
For the legs, most of the joints were created by joining two 45-degree beveled edges with hot glue. To make these beveled edges, I placed the piece of foam core on the edge of the table and used my utility knife as shown the second photo.