I remember convincing my parents to buy me the book How to Make and Fly Airplanes when I was in elementary school. Using that book, I learned how to make planes that were actually able to fly. The planes were so good that I found myself getting in trouble when the planes knocked things over in the living room.

It's a good thing I didn't have Rubber Band Engineer by Lance Akiyama back then, for I would have found myself in far more trouble. At $22.99, this book can provide hours of construction and engineering fun and even more fun hurling projectiles and grabbing things. Rubberband engineer cover Figure 1: Book cover of Akiyama's Rubber Band Engineer

Rubber Band Engineer is a real how-to book with detailed instructions on how to build things from items you probably have at home: paint stirrers, washers, pencils, popsicle sticks, duct tape, glue, tongue depressors and of course, rubber bands. As you can see from the list below, Lance Akiyama emphasizes building devices that can hurl things through the air. In other words, this book is about projectiles. Oh, the damage I could have done with this book. Here's what you can make.

  • Many-Thing Shooter
  • PVC Slingshot Rifle
  • Crossbow and bow-and arrow
  • Four kinds of catapults
  • Slingshot rocket
  • Helicopter
  • Extending grabber

There's not much to read in this book, it's about building things. With detailed instructions and lots of photos, the book provides steps you can easily follow, leaving out just enough detail for experimentation. After all, the whole point of engineering is to try things and see what works best.

There would be no point in reviewing this book (or any "how-to" book) without actually trying something. I decided to try the easiest thing first: a Pyramid Catapult. I'll explain my experience building it, then show a video of the catapult hurling things into the street. I used the catapult in a quiet holiday weekend to minimize foot or vehicle traffic. After all, the goal was not to cause any real trouble.

The pyramid catapult Figure 2: The pyramid catapult, built from instructions in Rubber Band Engineer by Lance Akiyama.

The Pyramid catapult was easy to build in about 15 minutes, though I did make some modifications to the design. For example, the instructions call for using tape at the corners only, where the pencils intersect. For added strength, I wrapped tape around locations with to parallel pencils. For the cup, I used a canister that once held a roll of camera film. This turned out to be better than a wider-mouthed cup, as you can see in the video. The barrel-shaped film canister helps the projectile travel lower and farther than did a wider cup.

The instructions don't specify the length of the rubber band. That's a good thing. I used a 3½-in. (8.9 cm) rubber band because that's what I had available. A slightly longer rubber band would have let the arm go back farther. But, had the author specified the rubber band's size, it would take away the incentive to experiment with different rubber bands. Fortunately, the projectiles landed before hitting the cars across the street.

The video below shows the catapult in action using several projectiles and two different cups.

*Rubber Band Engineer *can teach you how to build fun things. Just be careful not to get into too much trouble hitting people, breaking windows, or knocking over expensive items. A little trouble is ok, though.