Introduction: Mousetrap Car Racer

About: I'm Alec. I like to post Instructables whenever I get to work on my own projects. But, that isn't exactly all the time. I usually find myself pretty busy with school, so it's not often that I actually have …

Recently in Physical Science, we were assigned to construct a mousetrap-powered car.  After a great deal of research, I had a basic idea of what I wanted to make.  The end result is what you see.  This mouse trap car is more for speed than for distance, although it's performance seems to be between the two.  It goes a decent distance, and it travels at a decent speed.  While being lightweight, This car is also quite sturdy.  It's fairly easy to make, so give it a shot if you're interested!

Step 1: Materials

There are a few specific items that you'll need for this project, but you can probably use similar items if you aren't able to find balsa wood, copper tubing, etc. in the sizes that I used.  So, here's what you'll need for the project:

* 1 Victor mousetrap
* 1 pool noodle (try to get one with an inner hole that has a small diameter)
* 1 long piece of balsa wood (You will need two 8" lengths of this balsa wood.  I cut mine from one piece of balsa wood that was 1/4" thick and 1" wide)
* slender copper tubing (the diameter of mine was 5/32", but you can use a close size)
* 4 small screw nuts (these must fit over your copper tubing, ideally as close a fit as possible)
* 1 wing nut (like the others, this nut must also fit over your copper tubing)
* JB-Weld
* wood glue
* electrical tape
* string, yarn, twine, etc. (just make sure you can tie it and that it can wind easily)
* (optional) corner braces or similar item (as many as needed--I used two)

* a pair of pliers
* hacksaw or knife (to cut pool noodle with)
* (optional) miter box (for clean, square cuts when you cut the pool noodle)
* pipe cutters or something else to cut copper tubing

Step 2: Making the Body

The body of the car is comprised of only three parts: the mousetrap, and two pieces of balsa wood.  Your first deal of business is to remove some parts from the mousetrap.  To do this, I clamped the parts with pliers and yanked the pieces out.  You will need to keep the lever arm (indicated in the picture notes).  Next, cut your balsa wood into two 8" lengths.  My balsa wood was 1" wide and 1/4" thick, but you could probably use a different size.  Next, mark two dots on one piece of balsa wood.  Each dot should be 1/2" from the bottom and side of the wood, on both ends of the wood.  Holding both pieces of balsa wood together, I drilled where the holes should be.  Your copper tube (which will later become the axle) should fit loosely in the hole.  Next, make marks two inches from each end of the balsa wood.  This is where you will glue your mousetrap.  Finally, use wood glue to paste the mousetrap to the two pieces of balsa wood.

Step 3: Assemble the Axles

Step 4: Attaching the Wheels

Take your pool noodle.  Mark two 2" lengths and two 1" lengths.  I used a hacksaw and miter box to cut these.  These lengths of noodle will be your wheels.  Next, wrap electrical tape where your wheels will go.  Make the fit as snug as possible.  Wrapping the tape will take a LONG time.  Once you are done, the wheels should fit very snugly over the axles.

Step 5: Extending the Snapper Arm

Step 6: Using Your Car

Pull the snapper arm back.  Hook the loop in the end of your string on one end of the wing nut.  Pull the axle back to wind the string around the rear axle.  Wind the car up until the snapper arm is fully back.  Place your car on the ground and let go!

Step 7: Optional Reinforcement

One thing that did concern me was the durability of the car.  I decided to use balsa wood for the sake of making my car lightweight, but it also made the car seem less durable.  Just to be safe, I glued two corner braces where the mousetrap meets the balsa wood.  Mix together some JB-Weld, and apply a generous amount to the corner braces.  Then, put each corner brace where the mousetrap joins the balsa wood, as shown in the last couple of pictures.  After that, I decided to glue in another piece of wood at the front of the car.  The glued-in piece of wood keeps the snapper arm from bending when it is in its forward position.  Finally, I wrapped the snapper arm in electrical tape.  This likely won't do much, but it could prevent some scratching from the spring being placed on top of the copper tubing.

Step 8: Decoration (The Best Part!)

Finally, the actual fun part of making a mousetrap car: decoration!  You can probably tell that I had fun with mine!