Then put a stick on top so it over laps both of the sticks below. Take the scissors and make a notch on the end of the dowel for the string to catch on. The mouse trap project frame should now roll freely on the four wheels. With this tutorial, you can create your very own do it yourself mouse trap car and watch the amusement of your little one as they amaze and agonize about how they work. Both are smooth and thin, but also strong enough to turn the wheels without snapping.
The lever arm attaches to mousetrap wire with glue and wrapping with string. Your simple model moves forward a few feet, but how could you design it to go longer distances? First, wind the string so that the wheels are spinning forward. I didn't have precise enough equipment to drill holes for the axles in the exact right place, so a three-wheel design was going to be impossible. This article has over 1,027,644 views, and 49 testimonials from our readers, earning it our reader-approved status. To adapt a mousetrap car for distance you have to optimize your wheels at first. If you see wasted space on your frame, try removing it, or, if this is impossible, make holes in it with a drill to bring its weight down. B Mark on the two balsa mousetrap support pieces the left edge of where the mousetrap will be glued.
Attach the mousetrap spring to a big flywheel which has nylon fishing line wound around it. Day Post Mon Tue Thu Fri How to use LaTeX? C The screw eyes needed for this project will no doubt be the smallest size you will find. I found that the washers grip the dowel well enough to not need the glue. When the jaw trap closes, it pulls the string along with it. Bend one end into a loop, create a circle with the two sides of the loop and tuck the end of the loop through the circle. Anything long, light, and not too flexible will work for the lever.
Wheels with large amounts of rotational inertia are helpful in some ways, because once the wheels are moving they will be difficult to stop. An axle support of thin steel has less friction than a hole drilled through a wood block. When the trap snapped closed, it yanked the string forward. As the string was pulled, friction between it and the axle caused the axle to rotate, spinning the wheels and moving the car forward. B Tarp straps can be found in the automotive section, some stores only sell the cloth-covered bungee cords which is not what you want. Whoever can build a car that drives the longest distance, wins.
If your rear axle is extremely skinny, your mousetrap car will be able to turn it more times for the same length of string than it would if it were wider. A longer arm travels a greater distance and allows more wraps of string around the axle. Secure them around the wheels as shown in the image. Don't use metal bolts, however; they add weight. In practice, this means that once they start rolling, they're harder to stop rolling. In the above equation, we see that V is always constant regardless of how fast the car gains speed keeping everything else the same. It is controlled by the length of the lever and the ratio between wheel diameter and axel diameter.
Strong fishing line or even dental floss would be better choices. Many guides recommend sturdy balsa constructions or balsa reinforced with metal to give a sturdy yet light lever. Large wheels travel farther with each rotation than a smaller wheel. Doing this increases the structural strength of the car while minimizing the change to its air resistance and weight. C Hot glue the small wood blocks at the edges in front and in the rear. For the purposes of your mousetrap car, this will mean making your frame both narrow though it will be difficult to get your frame any narrower than the mousetrap itself and vertically skinny.
Design 2 First of all, in order to allow immediate motion, I attached the string to a lock washer, preventing it from hitting the outside of the wheel. Lower the mass of your vehicle for best distance. If the line is longer it will not come off the axle at the end of the lever arm stroke. B Hold the pieces together until the hot glue has cooled enough to start to set. The above procedure used rubber bands to provide traction; can you think of a better way? However, it is worth mentioning that this equation is an approximation, for two reasons: First, it assumes that there are no friction losses. Installing a shorter lever arm is the best way to adapt a racer for speed.
For the wheel, use a material with a rough texture around the outside to give the wheel traction. This was abandoned because the larger surface area causes the car to use energy overcoming friction rather than travelling forward. Eliminate friction between the axle and the frame. For example, yarn isn't a good choice because it is prone to getting caught and has lots of friction. It may be helpful to use a stick to prop the trap open. The aim of is to build a subreddit frequented by physicists, scientists, and those with a passion for physics. The smaller the mass of your car, the better — every gram or milligram you can shave off of your car's frame is a little further your mousetrap will be able to push your car.
A The small screw eyes I used were from two manufacturers and were slightly different sizes but both worked well. Every time your axle turns one time, so do your wheels — if the wheels have a much larger diameter than the axle, the car will go further on each turn of the axle than it would if the wheels were smaller. How to Build a Mousetrap Car Woodwork Guide Home Woodworking Plans How to Build a Mousetrap Car. Axle is straight now and the car should run straighter. The cars physics are all about mechanical advantage, the trade off between how long it takes to do something and how little force is required to do it. It's also important to take the weight of the wheels themselves into account — any unneeded weight will ultimately slow your car down or lead to added friction. A The razor blade appears to cut plastic sections used for wheel spacers better than using a scissors.