My very first printer was a paste spewing Fab@Home Model 2. I enjoyed building it and learned a lot. But when the project was abandoned, I was dismayed, especially since I was able to briefly run it as a CNC machine. The problem was always the proprietary motors and controller. I hated that. So I converted mine to use ordinary steppers and a Sanguinolou board. I am still working out print heads but I've solved the linear motion problems. I am also converting out of belts to use leadscrews which give smoother more predictable motion.