DIY Projects

CD drive scrounged junkbots

After exploring the innards of our CD drives, students in my robotics class are coming up with some clever junkbots. Here are a few of the first ones, more to come as they evolve.As the school year begins, how do you help students understand the basics of electricity, manufacturing, and creating original devices? As a student, what are the best projects for the start of the semester or school year to get you excited to go deeper and learn more?

Make: Projects – “Pepakura-cast” metal pyramid puzzle

Make: Projects – “Pepakura-cast” metal pyramid puzzle

The idea of a hollow card or paper form buried in plain sand as a sacrificial mold for poured metal parts interested me. As the internet papercraft explosion has taught us, paper is really not a bad medium for 3D design, especially for the cost. Software like Pepakura will convert any 3D digital model into a papercraft one that can be printed out, cut out, folded up, and glued or taped together to make a reasonably accurate real-world replica of the original. What if, instead of using the paper as a positive representation, one were to use it simply as a negative space–a volume, supported by dry sand, that would survive just long enough to impart its form to molten metal poured inside?

As a first experiment, I designed a paper template for the pieces of a classic put-together puzzle often called “The Four Piece Pyramid.” The challenge is to use the four identical pieces to form a symmetrical three-sided pyramid. I chose this as form, first, because I think the puzzle is elegant; second, because all four pieces are identical so only one template design is required; and three, because the pieces are fairly simple, geometrically, and thus so are the templates.