Lettera

Lettera is a small, cheap CNC machine for learning how digital fabrication works. The budget was under a hundred euros, so most parts are laser-cut, with an Arduino at the core.

The firmware is deliberately basic, built on the standard Stepper library and editable in the Arduino IDE, so a beginner can open it, understand it, and change it. Mechanically, the challenge was getting enough rigidity and precision out of laser-cut parts while keeping everything simple.

The result is a working plotter with output that feels warmer than an inkjet print, and an open, transparent entry point into CNC and embedded systems.