G-CODE → 2026-01-19

Learning to control a 3D printer through G-code. This is the language computers use to tell printers what to print — a long list of commands where to move and how much plastic to extrude.

Usually G-code is made by slicers: they take a 3D model, slice it into layers, and generate commands. But you can write G-code by hand! Then you can print not layer by layer, but up and down — creating lacy structures that a slicer couldn't handle.

Though if you mess up a digit, the printer will crash into the part at full speed and wreck everything with terrible sounds. Don't ask how I know this.

Tinkered for two days, got something cool. This is a one-dimensional cellular automaton — different steps are visible along the cylinder axis. I like the texture, like it's knitted.

In G-code viewer it looks like this

And in slicer like this