From Fidget Keychain to Functional GameCube Controller

Brux found a GameCube controller keychain at Backpack Buddies, one of those tiny plastic copies that moves and feels much like the real thing. Most people would simply clip that thing to their keys and forget about it, but Brux was intrigued. Imagine if he disassembled it and turned it into a fully functional GameCube controller rather than just a souvenir.

Once Brux had separated the two halves, he discovered that the inside of the shell was a miniscule space, with hardly enough room to fit any standard parts. So he chiseled off even extra space with a trim, a delicate procedure that required steady hands, before printing some unique mounting components on his 3D printer. These little printed parts barely held the switches in place with the original button positions. To make things as neat as possible, he used tiny surface-mount switches that he put directly onto the printed mounts. There are no circuit boards clogging up the works. Brux employed ultra-thin enameled wire that was nearly undetectable to connect the switches to the main board. He also had to trim the plastic posts on each button so they would fit properly and click cleanly again.

The analog stick also required some TLC, so he attached a handful of sensors to detect movement in various directions. The whole contraption had to be kept tiny so that when he closed the shell, everything fit securely with no bulges or holes visible. A small RP2040 board was at the heart of the operation, reading the switch and stick locations and translating them into the correct format so the GameCube thought it was using the genuine thing. Best of all, the little controller connected directly to the console, no adapter required.

The final piece of the puzzle came when Brux meticulously disassembled an actual GameCube controller, removing everything except the wire and plug and leaving behind the authentic connector. This was the critical component that allowed the finished keychain to plug directly into any port or suitable adaptor. The wire came out of the shell looking clean and tidy, just like the actual thing. The next step was to glue the buttons and stick cap back in place, followed by testing each input.
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