Racecar Book: Build and Race Mousetrap Cars, Dragsters, Tri-Can Haulers & More

Racecar Book: Build and Race Mousetrap Cars, Dragsters, Tri-Can Haulers & More — page 7
How to Make Great Racecars Friction is important for a good racecar Friction is a force that opposes motion but fric tion also keeps the wheels from spinning in place A racecar driver never wants a wheel that spins in place Friction depends on two things weight and the types of surfaces in contact Rubber is a great material because it provides a lot of friction which is why you play basketball vol leyball and tennis in rubber-soled shoes Wrapping a rubber band or a piece of a balloon around your wheels can increase friction and off your car will go Weight is a tricky thing with your car Too much weight and it won’t go very far But too little weight and the wheels will just spin in place Adding weights like coins and soda cans may actually make some cars roll farther Experiment to find the best combination to help your car go The key to science is experimentation Feel free to modify any of the plans in this book if you have a better idea you won’t know unless you try Wheels To roll you need wheels Save every round thing you come across CDs bottle caps jar lids and plastic can covers like those from Pringles cans all work well Another great source for wheels is old toys Save the wheels from any broken toy before you recycle the rest A relatively cheap and lightweight wheel can be found in stores that sell fake flowers Round Styrofoam discs are used in floral arrangements and also make great lightweight wheels You can also buy wheels at hobby stores which sell a large variety of wheels for remote control cars and planes For maximum speed and distance store-bought wheels are hard to beat Many are made from high density foam which leads to lightweight tires and great friction that blast off from the starting line But store-bought wheels take cash and planning Every 2 K O O B R A C E C A R E H T