How to Make the Simplest Mouse Trap Car

Save the mouse for a more humane trap and create a car from these old-school mouse traps.

Mouse trap cars are a good way to teach elementary principles of physics and motion while also teaching basic mechanical concepts in constructing small scale models of moving vehicles. A mouse trap car can be easily put together in an hour or two. Be careful not to let kids get their fingers caught in the mouse trap while working on the project.

Things You'll Need

• 4 CDs
• Rubber bands
• 2 dowel rods
• 4 eye hooks
• 4 rubber washers
• 4 metal washers
• String
• Hobby putty
• Tape
• Glue
• Scissors

Instructions

1. Screw in the eye hooks to the base of the mouse trap so that the hooks extend out from the width of the mouse trap. The eye hooks will secure the axles to the mouse trap. Be sure that the hooks leave enough space for the dowels to rotate efficiently. If the hooks are disproportionately larger than the axles then the axle will vibrate while rotating, making the mechanical motion of the spring of the mouse trap less efficient.

2. Hold the metal washers to the eye hooks while sliding the axle through the eye hooks. Insert the CDs onto the axles. Secure the CDs to the axles with hobby putty and glue. Slide the rubber washers to the outside of each CD, which will help to fix the CD in place and absorb vibrations when the mouse trap car is moving. The order of components for the axle from the inside to the outside of the axle should be eye hook, metal washer, wheel then rubber washer.

3. Tie and glue the string to the cross-arm bar of the mouse trap.

4. Use a hobby knife to cut a notch in the middle of one of the dowel rods so that the notch is directly aligned with the center of the mouse trap's arm, where the string is tied. The notch will serve as a guide for the string.

5. Set the mouse trap so that it is loaded. Wrap the string around the dowel where the notch is located. When the mouse trap is sprung, the string will unwind, causing the motion of the spring to be transferred to the axle. It is important to know that the car will travel in the opposite direction from the string's coil.

References

• Mouse Trap Car
• Mouse Trap Cars: Mouse Trap Car And Vehicle Propulsion Theory
• PBS: Building A Better Mouse Trap Car

Resources

• Hellstern Springdale Schools: Mouse Trap Car
• Science Guy: Mousetrap Cars
• MiniScience: Mousetrap Powered Car