Materials (per car) 

One sheet of 8.5"x11" size paper.
Three standard paper clips 
One large paper clip.
Two plastic straws. 
One fourth sheet of poster board. 
Narrow masking tape. 
Three rubber bands-size 32


Drawing compass 

(refer to diagrams)
Parts Diagram     Assembly Diagram


Place your pencil along the long edge of the sheet of paper. Roll the paper very tightly around the pencil to form a tub. Tape the tube with 4 small pieces of masking tape and remove the pencil. This tub is the body tube. Next, pull apart the two loops on one of the standard paper clips until the loops are about 30 degrees apart. Slip one of the loops inside one end of the body tube. This paper clip is the front hook. 

Motor Mount

In your materials you will have one sheet of poster 12.7 cm x 10.2 cm. Fold this card so that the 12.7 cm edges meet. You should now have a double-thick 12.7 cm by 5.1 cm rectangle. Now fold the double card so that the 5.1 cm edges meet. When you open the fold, you should have two 6.4 by 5.1 cm rectangles, each of which is two layers thick. Crease each of the rectangles around 1/4" from the last crease you made. Then fold the card at the creases. Your card should now look like an "M". This is the motor mount. A soda straw should fit in the hollow or Finally, trim the edges of the mount as shown. 

Locate your poster board in your box. Put a pencil mark in the middle of the card and draw a line to divide both sides. You now have two rectangles. Find the center of each. Take a compass and draw two large circles on each side (radius =4.5 cm). These circles will be your large wheels. Now draw two smaller circles (r=2.1 cm) on the small rectangle of poster board. Don't forget to find the center of each side before you draw the circles. Make a very small hole in the exact center of each circle be using a metal punch provided by your instructor. Now cut the circles out very carefully. Use sandpaper to smooth out the wheels. 

Axles and Propeller Shaft 

To make your axles and propeller shaft, locate the pliers and begin to unfold the paper clips as you would a pocket knife. Use pliers and a hammer to straighten the clips out as much as possible. Be careful not to twist the clips or hit them hard with the hammer or they may break. The long wire is your rear axle and the other two are your front axle and propeller shaft. Set the wires aside momentarily.

Take one large soda straw and cut it 10 cm for the rear axle. Take the other part of the straw and cut it 6 cm for the front axles. The other large straw can be used for the propeller tube. Now make another 90 degree angle about half way from the same bend. Take the 10 cm straw and put the large paper clip through the straw. Bend the other with the pliers the same way the other side was bent. 

Power Supply 

Cut the last straw to be used for the propeller tube and tape it to the motor mount. Design and cut your propeller out of the material you have selected. Make sure you find the center before you cut out the propeller. Take the last paper clip and bend it as shown in the diagram. Take three rubber bands and tie them together. Hook the rubber bands to the curved end of the propeller shaft and to the front hook. 


Select a piece of poster board for your propeller. The design is up to you. The propeller will hit the ground if it is to large. Make sure you locate the center of the rectangle before you cut the propeller out. 

Final Adjustments 

 Add a twist to the ends of the propeller so that it will screw into the air and push the car forward. Wind the propeller about a hundred turns and place the car on the floor or a table. Release the propeller a split second before you release the car. 


If your car wonít go donít despair. Donít approach your teacher for help right away - do that only as a last resort. First check your Air Car against the cars built by your teacher or by successful classmates. Look yours over carefully to see whether you can discover the problem. A number of correctable things could be at fault. Here are some possible construction flaws and ways you can fix them: 

1. The propeller is not turning. It might be hitting something. Adjust by bending or tape it again in a better position. 
2. The propeller is spinning, but the car isnít moving. Compare your car with the teachers to see whether your carís propeller blades are bent properly. Try adjusting the twist in them. Spin the wheels. If they are stiff, the axle may be bent and rubbing inside the axle tube. Straighten the axle. Place the car on thefloor and give it a gentle push. If it should not roll, the wheels may not be perfectly round. Sand the edges. 
3. Your car is going in circles. Try turning the axle tube and the motor mount slightly to one side. 
4. The Air Car is flipping over This could be caused by a number of things. The propeller may be too long, the rear axle may be to short, or the rubber bands may be wound too tightly. 
5. The body tube of the car folds up. Place the pencil back in the body tube for support. Make sure you donít wind the rubber band to tightly. 
6. Your carís wheels are folding or the propeller is flopping around and not working. These problems indicate that the L shaped ends of either the axles or the propeller shaft are not properly taped to the outside of the wheels or to the propeller. Remove the old tape and attach the ends properly.