You would need to spin the first gear 1 trillion times per second from now until the last proton in the universe decays, then do that about 10^68^ more times. 10^68^ is roughly equal to 52!, the number of unique ways a deck of cards can be shuffled. There's a somewhat famous description of how large this number is (paraphrased for brevity):

Start a timer that will count down the number of seconds from 52! to 0. Every billion years, take a step along the equator. Every time you go around the world, remove one drop of water from the Pacific Ocean. Every time you empty the ocean, take one sheet of paper and place it flat on the ground. Every time the stack of paper reaches from the Earth to the Sun, take a step up Mount Everest. Once you've reached the summit 80 times, the timer will have reached 0.