I began by finding images of rocket ship forms that matched what I had in mind. I was heavily inspired by both the rocket from the Tintin adventure Explorers on the Moon and the Raygun Gothic Rocket currently near the San Francisco Ferry Building (the creators of whom I gave my first physical prototype).
Whereas both the rockets which provided inspiration had three fins leading from the body of the rocket to the ground, for simplicity's sake I went with four. This allowed me to draw two full-height cross sections of the rocket, which could then interlock providing the main structure of the model. I then worked out the sizing and placement of the ribs - and created the initial design...
I used a P2 sheet of the 4mm Single-Layer Corrugated Card available from the Ponoko USA hub - and key to the flexibility of the design was that I kept a working version of my design before saving the version that I uploaded to my Ponoko Personal Factory and had made.
The way that I created each of the slots, and split the circles into the ribs I required was drawing specifically aligned and sized rectangles over the main parts of the design. I could then use the Pathfinder window 'Minus-front' command in Illustrator to remove the rectangles from my main rocket ship shapes. The equivalent of this command in Inkscape is Path > Difference. I'll be writing about these totally vital commands in more depth soon.
Once these commands are used, any ease of flexibility you had to adjust the thickness or depth of your slots is gone. As a result, you want to save a working version of your design prior to using these Minus-front or Difference commands. The working version of my original design looked like this:
To make things easy for myself, I left all the lines in my working version black instead of the correctly formatted blue - to make it very easy for me to see what was to-be finished off before saving the upload version.
I kept working versions of the design at all stages - so that I could eventually add further structural support by adding more slots on the main sections, and little tabs on the ribs of the rocket. I also experimented with making the rocket in different thicknesses of cardboard and at different sizes. My ever-growing working document was absolutely integral to my prototyping process - and provides everything required to adapt the design for any other material size, thickness and type.
You can see the current state of that working document below, and I've attached the actual Adobe Illustrator file to the bottom of this post as well - which you are welcome to download and adapt however you wish.
I'm not 100% sure what is next for the rocket ship project. I added small holes in a batch of mini rockets I put together so that they could be hung as ornaments, which is fun. I'm considering adapting the design into a lamp - or perhaps a Spice Rack.
If you make one of the rockets or adapt the design, I'd love to hear about what you did - reply here in the forums or let us know via Facebook or Twitter!