Download Article
Download Article
A mousetrap car makes for a great science project, physics classroom experiment, or a fun weekend activity. Mousetrap cars are frequently used to help students learn about mechanical advantage, distance, and gravity, with many teachers turning the experiment into a long-distance challenge. The stored potential energy in the spring of the mousetrap's snapper arm transforms into the kinetic energy that propels a car that you will make. But to create your own rodent roadster, you'll need the right materials, an understanding of a few physical principles, and a little effort.
Steps
-
Visualize your mousetrap car. You're going to need to attach your mousetrap to a chassis (or body), which will form the frame of your car, wheels, and an engine to power the contraption. These kinds of miniature cars are often used for physics experiment when learning about mechanical advantage, gravity, and gear ratios. For the purposes of this example, heavy cardboard will be used as the chassis, but you also might use: [1] X Research source
- Foam core.
- The body of an old toy car.
- A piece of light, durable wood, like balsa wood.
-
Use physics to your advantage for best results. You can modify the design of your car to achieve certain goals. For example, if your physics class is having a distance race competition, you'll want to:
- Lighten your car as much as possible. If using a solid chassis, this might include drilling holes in its frame and wheels.
- Use wheels that are both thin and stiff.
- Decrease air resistance by making the front of your car small and sleek.
Advertisement -
Take into account the surface your car will run on. If your car will be traveling up a ramp or across hilly terrain, smaller wheels will be able to manage the incline better due to inertia. Flat surfaces, like table and floors, can be best traversed with larger wheels.
-
Gather your mousetrap car making materials. As previously mentioned, there are many different materials you might use to make your mousetrap car. Some additional options are listed in the "Tips" below. However, to make the mousetrap in this example, you will need: [2] X Research source
- Compass (for drawing circles)
- Duct tape
- Durable string
- Elastic bands/rubber bands
- Eye hooks (4)
- Heavy cardboard or foam core
- Mousetrap
- Pliers
- Ruler
- Thin dowels (2)
- Utility knife
- Protractor
Advertisement
-
Make the wheels for your car. You'll need to create four wheels out of your heavy cardboard or foam core. To do this, take your compass or some other round object and your pencil to trace your wheels-to-be onto the cardboard. In this example, one inch (2.5 cm) diameter front wheels and two inch (5 cm) diameter rear wheels were used. After you've traced your wheels:
- Use your utility knife to cut your wheels free.
- Attach rubber bands around the outside edge of the wheel to give the wheels additional traction.
- You might also use CDs, DVDs, and vinyl records to make your wheels. [3] X Research source
- NOTE : In this example, larger back wheels and smaller forward wheels are used.
-
Remove dangerous teeth from the snap-arm of your trap. [4] X Research source Take your mousetrap and find the rod that is used to set it. There will likely be sharp teeth at the end of the rod. Carefully remove the rod, and if it has any sharp teeth, use your pliers to pull these free.
-
Fashion your chassis from your heavy cardboard. To accommodate your mousetrap, you'll need your chassis to be about ½" (13 mm) bigger on all sides than your trap. Measure and mark this out on your cardboard, and then use your utility knife to cut out your chassis from the cardboard. [5] X Research source
- Balsa or basswood make a light but more durable body for the car.
-
Attach your mousetrap to the top of your chassis. Center the mousetrap on top of the chassis and then, using duct tape or clear packaging tape, secure the mousetrap into place on all 4 sides. [6] X Research source
- While taping your trap into place you should avoid taping the spring. The spring should be found in the middle of the trap and snapper arm.
-
Align and attach your eye hooks to the bottom of your chassis. These eye hooks will hold the axle rods, which are the rod on which you will attach your wheels. If these hooks are out of line, your car won't travel straight, so you should: [7] X Research source
- Use your ruler and a pencil to mark the location of your eye hooks in the four corners of your chassis.
- Double check the marks are evenly lined up with your ruler.
- Screw the eye hooks into place through the cardboard chassis where you have marked.
-
Create your axle rods. Cut 2 thin skewers to a length about 4 centimeter (1.6 in) longer than the width of your eye hooks. These dowels/wooden skewer sticks will be the axle rods for the wheels that you made. They should be thin enough to slide through the eye hooks and spin freely.
- Eye hooks that are too thick or skewers that are too thin will cause the axle rod to pivot in its eye hook holder, which could affect the alignment of your car.
-
Attach your wheels to your axle rods. You should be able to poke holes in the center of each wheel with the point of your compass. This should create holes that are slightly smaller than the dowel rods. [8] X Research source Then you should:
- Wind a rubber band onto your axle so that it is close to the body, but not touching it. This will form a buffer between your wheel and the chassis of your car, but can create friction if it comes in contact with your chassis.
- Push your wheels onto the axle rods. If you have larger drive wheels, these should go on the rear axle and the smaller wheels on the front axle.
- Your axle dowels should extend past your wheel about 1" (2.5 cm).
-
Prevent your wheels from coming off or unaligned. You can do this by wrapping a thin elastic band around your dowel just outside each of wheels. The elastic band will keep the wheels from falling off of the car. [9] X Research source
Advertisement
-
Tie your string to the snap-arm. Carefully lift the snap-arm just enough to slide one end of your string beneath it. Then, wrap the string around the snap-arm and tie a tight knot to secure the string.
- A general knot, like a square knot should work fine for attaching your string to the arm of your trap.
-
Cut your string. Before you do, make sure that it is long enough to reach past the car's rear axle. The longer the string, the longer time it will take for the force of your trap to be released, which will create slower acceleration but greater distance traveled. [10] X Research source
-
Prepare your transmission string. Your string is the part that will transfer force from the spring mechanism of your mousetrap to the rear wheels of your car. Pull back the snap-arm and hold it securely. While you are holding the snap-arm:
- Use your free hand to wrap the string tightly around the car's rear axle.
- Continue winding until no string remains.
- The string should be tight enough to hold down the snap-arm when held.
-
Prepare for a test drive. Place the car on the ground while still holding the snap-arm. Make sure you have a good grip on the end of the string. This should keep your snap-arm in place, and releasing should cause the arm to snap forward, propelling your car.
-
Release your car and watch it go. Move your hands clear of your mousetrap car and let go of the string. The kinetic energy of the mousetrap spring will transfer through your string to your rear axle, causing your mousetrap car to travel forward a few feet, depending on construction and the length of the string. [11] X Research source
Advertisement
Community Q&A
Search
-
QuestionWill this car go farther than 2 meters? How far will it go?Community AnswerIt depends on the size of the string. To make it go farther, I would add a stick addition onto the trigger arm to make it longer. This also makes the string longer. Increasing the length of the chassis will also help with distance.
-
QuestionWhen building a mousetrap car, what is the proper way to tie the string and rubber band?Community AnswerGo over the top of the axel. then loop around, making sure the string crosses over itself. Then slowly lift the arm of the trap and spin the wheels to continue wrapping it.
-
QuestionWhat is an alternative to using the eye hooks?Community AnswerIf your dowels are thick enough, cut sections of straws and hot glue them to the bottom of the chassis.
Ask a Question
200 characters left
Include your email address to get a message when this question is answered.
Submit
Advertisement
Video
Reader Videos
Tips
- Be sure to clear a path in front of your mousetrap car. Obstacles may break the fragile design.Thanks
- If you don't have thin skewers, straws are a good replacement.Thanks
- You can replace the cardboard body with a stronger, wooden one, but remember it will be harder to add the eye hooks and cut the wood. Use tools at your own risk.Thanks
Tips from our Readers
The advice in this section is based on the lived experiences of wikiHow readers like you. If you have a helpful tip you’d like to share on wikiHow, please submit it in the field below.
- Add a metal washer onto your axle close to the frame in front of the rubber band to reduce risk of friction.
Submit a Tip
All tip submissions are carefully reviewed before being published
Name
Please provide your name and last initial
Thanks for submitting a tip for review!
Advertisement
Warnings
- Never try this project with a rat trap. If the snapper arm of a rat trap releases early, the force could easily break someone's finger.Thanks
- Young children should only assemble a mousetrap car with adult assistance.Thanks
Advertisement
Things You'll Need
- Compass (for drawing circles)
- Pencil (for drawing circles)
- Duct tape
- Durable string
- Elastic bands/rubber bands
- Eye hooks (4)
- Heavy cardboard or foam core
- Mousetrap
- Pliers
- Ruler
- Thin dowels (2)
- Utility knife
References
- ↑ https://www.llbcl.ca/public/download/files/178460
- ↑ https://extension.unh.edu/sites/default/files/migrated_unmanaged_files/Resource006444_Rep9240.pdf
- ↑ https://www.aesdes.org/2021/04/03/design-preview-mousetrap-car-2-0/
- ↑ https://learning-center.homesciencetools.com/article/mousetrap-physics/
- ↑ https://www.eng.ufl.edu/secme/welcome-to-the-2023-2024-secme-competition-year/mousetrap-car/mousetrap-car-design-competition-middle-and-high-school/
- ↑ https://extension.unh.edu/sites/default/files/migrated_unmanaged_files/Resource006444_Rep9240.pdf
- ↑ https://www.learner.org/series/project-playbook-educator-edition/mousetrap-car/
- ↑ https://www.llbcl.ca/public/download/files/178460
- ↑ https://www.learner.org/series/project-playbook-educator-edition/mousetrap-car/
About This Article
Article Summary
X
To build a mousetrap car, start by making 4 wheels out of heavy cardboard or foam core. Carefully remove the teeth from the mousetrap, then fashion a chassis from heavy cardboard and attach the trap to the chassis with duct tape. Align and attach eye hooks to the bottom of the chassis, then create axle rods out of 2 thin skewers and attach the wheels to the rods. Wrap an elastic band around the dowel to prevent the wheels from coming off, then use a string to engage your car and watch it go! If you want to learn how to design your car based on the surface it's driving on, keep reading the article!
Did this summary help you?
Thanks to all authors for creating a page that has been read 1,244,814 times.
Reader Success Stories
- "I was looking for a basic how-to to send someone else, and this fit the bill very nicely with the pictures while pointing out ways to decrease resistance. My kids did these for years for distance competitions. Thanks for posting!" ..." more
Advertisement
"I was looking for a basic how-to to send someone else, and this fit the bill very nicely with the pictures while pointing out ways to decrease resistance. My kids did these for years for distance competitions. Thanks for posting!"
..."
more
"Everything helped. I am doing a science project, and this explains everything step by step. If something isn't covered in the instructions, the kind wikiHow contributors are there to help."
..."
more
"Every single step is so well detailed! I did this for my robotics class and it came in number 1 due to the distance. Thanks. "
..."
more
"I had to build a mousetrap car for my school project and I did not know what a mousetrap car was. I recommend this site."
..."
more
"I liked how you put lots of details and information as you where doing it, thank you very much!"
