溜溜球制作教程双一泊解

the yo yo， it may look like a kid's toy， but this twenty first century version is used for competition sport how does this device pull off gravity to find tricks and effortlessly return to your hand deceivingly simple on the outside this miniature machine is packed full of surprises silicon o rings grip the string to accelerate the spool precision balanced aluminium rims produce extra spinning momentum that rotates the yo yo as fast as the blades of a jet engine an intricate ring of bulberry cut friction and make impossible tricks possible the secret to keeping a yo yo stable in flight lies in how engineers build and balance its intricate parts workers of this florida factory must distribute the yo yo's weight evenly on both sides first step cast two identically shaped halves okay so today we're gonna be setting up a yo yo master croftsman arnold has spent seven years building yo yos， he forms the two hearts of the the yo yo inside precision engineered brass molds this is your mold and your mold is gonna be filled with multiplastic that is gonna form the yoyo， the specific design that we're looking for is going to be created in this little cavities here he needs a precise setup to squeeze molten plastic into these tiny spaces and this is a complete setup look like and now it's ready for the processing which would be in the injection modeling machine arnold's mold must withstand eighty tons of pressure to prevent any injected plastic leaking out it weighs over two hundred kilograms okay well， next step would be our raw material and it's like little colored forms there's gonna be melted and shut into the cavities to create your yo yo the machine melts the pellets at two hundred and sixty degrees he then pumped the molten plastic into each cavity too much or too little in each mold and the yo yo want balance if you look at these this is what you're looking for perfect finish a balanced design allows a yoyo to throw and return smoothly but to perform the ultimate tricks the yoyo must keep spinning at the end of the string without slowing down to do this the yo yo contains an ingenious device smaller than a penny ten steel balls roll between the inner and outer rings they work together to cut friction between the layers as the string grips the outer cylinder the inner ring can keep spinning at full speed as fast as the engine of a formula one car this brilliant bearing can keep the yo yo spinning at the bottom of the string for over ten minutes to generate even more spin workers add extra weight to each half the heavier the yo yo the longer it takes to slow down these are for the outside of the yo yo to give it more weight for the stronger spin and better play peter uses aircraft grade aluminium to sculpt special metal rims they must be accurate to one tenth of a gram so the finished yo yo spins true they don't fit just snug enough then the yoyo could be out of balance and the little weight on one end could throw it out work is assembled a yo yo and add an axle to hold the two halves straight a quick spin make sure the two halves balance perfectly these super fast yo yos can't guarantee success， but they do give players a fighting chance。