Just found this guy on YouTube who made the simplest homemade CNC build I’ve ever seen. He uses a granite slab as the base and a thick steel piece bent to 90 degrees as the Z-axis. In another video he talks about the play in the machine, I linked the rigidity test and showcase videos below. For what it is, the thing seems surprisingly stable, even with some 3D-printed parts. i assume the build costs a bit under $1000, which looks like a way better deal than most off the shelf machines you can get at that price. Definitely got me interested in trying something like this once I can budget for it. Let me know what you think! Link to project: https://www.youtube.com/watch?v=chF1msLMxqc Link to Rigidity test: https://www.youtube.com/watch?v=Nf0gFT7_pA0&t=306s