Learning about force and motion is great fun when you build a propeller car because it can be designed in so many ways with different materials like balsa wood, empty water bottles, milk carton, rulers – anything, really, as long as the wind from the propeller can push its weight. Purchase wheels and axles from a hobby store or a carpenter who can custom-cut wooden parts. In addition, CDs are also good wheels. Whatever you use, make sure the wheels fit snuggly on the axles. Start simple and then surprise yourself and others by inventing a completely new version of this fun toy! See the links below for more inspiration. See “Video” on Maker Kids (www.maker-kids.org) for a demonstration of Propeller Car making.
Tools and Materials:
Hot Glue Gun
Wooden Ruler or Balsa Wood
Foam Rubber Block
Wooden Dowels/Other for Axles
Plastic Drinking Straws
Double-sided or Velcro tape
Toy DC Motor
1.5v Battery and Single Battery Holder
Choose the material for your car body (e.g. balsa wood, a wooden ruler or foam blocks that can be purchased online or from a hobby store). If it’s balsa wood, cut it length and width wise, to your desired size.
Measure the width of the car body. Cut two drinking straws to fit the width, cut them to size and hot glue them onto the body – carefully positioning them so they keep the car body steady and stable when the motor is glued on one end. (Hint: Look at how wheels and axles are aligned in real cars.)
Cut wooden dowels for axles so that, depending on the car wheel size, with the wheel on the axle there is slight clearance from the car body. See the instructions for Pinewood Racers for information on wheel and axle alignment.
Insert the axles into the straws and attach the wheels.
Then insert the rod of the motor into the propeller and place the motor at one end of the car body to see if the propeller hits or clears the ground when it spins. If it hits the ground, build a stand from a foam block or balsa wood. Remember: The lighter the car, the better.
Attach the motor to the motor stand and the motor stand to the car body at one end with electrical tape or hot glue.
If the battery holder has wires make sure they can touch the prongs of the motor from where you plan to tape or glue it on the car body.
Glue the battery holder down on the car body. Connect the wires (or alligator clips) to the motor. The circuit is completed and away the Propeller Car GOES! Note: A battery holder is optional. A rubber band can also be wrapped around the length of a battery. The battery can be taped down to the car body. Alligator clips or just a simple wire (stripped at both ends) can connect the battery to the motor.
See the gallery for photos of cars that will inspire your imagination.
Propeller Racer Kit: http://shop.pitsco.com/store/detail.aspx?ID=1504&bhcp=1
Super Propeller Car: http://www.wired.com/autopia/2010/06/downwind-faster-than-the-wind/
Wheel Alignment: http://en.wikibooks.org/wiki/How_To_Build_a_Pinewood_Derby_Car/Assembly