Warning: Do not build this. It’s dangerous and will probably burn your house down.
At the ripe old age of 30-ish, I’m willing to admit that I don’t really get Twitch. It’s a platform that lets you stream whatever you’re doing — often that’s playing a video game — so that your subscribers can watch. The most popular Twitch streamers, who mostly seem to play Fortnite, have millions of subscribers. But, for people with fewer followers, getting a new subscriber is a big deal. Jesse Congdon wanted a way to thank new subscribers for following, and so he built this huge laser engraver to burn their names into wall art.
Before I go into the details, I need to point out again that this is dangerous, and you really shouldn’t replicate it. While Congdon seems to know what he’s doing and only runs the laser when he’s there to supervise it, it’s still a machine meant to burn material that’s attached to the wall of his home. Fire hazards aside, the build is impressive. It’s laid out like a conventional laser cutter/engraver, except that the Y axis is vertical and the whole machine is mounted to a wall.
When Congdon — “oh_bother” on Twitch — gets a new subscriber while he’s streaming, the machine finds an empty spot on a piece of plywood and engraves their name. A Raspberry Pi 3B + is used to monitor his Twitch logs via their API, and identifies when a new person subscribes. It then chooses a place where the subscriber’s name will fit, and sends the G-code to the machine’s GRBL controller to be engraved. While I, once again, need to stress that you shouldn’t build this, it is a really cool way to show subscribers some love by commemorating them on wall art.