Spread across two tables, this intricate series of marble physics tricks is the culmination of weeks of work by chain reaction YouTuber Kaplamino. Blue Marble 3 is based on their Blue Marble video from 2018, but levels up the complexity with a rotating track, a suspenseful slide, more magnets, rubber bands, a tape measure, lots of string work, a water trick, a fire catapult, and two air tricks powered by balloons. From the video notes:
Magnets & Marbles, Dominoes and Fire, Green Ball Adventure, a Sprice Machines chain reaction, Murmelwelt’s Cuboro/Cugolino “big ball” marble run, and The Lemonade Machine.
The air loop is very fun. The two main challenges were first to inflate the balloon with exactly the amount of air it takes to make 3 turns of the loop, and then to push a plug into the balloon (a small magnet with exactly the right size by coincidence) with exactly the right strength to hold it well but not too much :p You can see big magnets everywhere to recover the plug and prevent it from blocking a track, it was pretty unpredictable to know where it was going to jump. I couldn’t put a large magnet too close because it could stop the two small magnets from getting closer or tear the cap off too soon.