NEMA for better feeding

[andreisperid]

Instead of the small 28BYJ, a NEMA stepper motor could be used to increase the feed speed, precision and reliability.

Since there is no need to use both the char and feed at the same time, I had the idea of having a single A4988 driver to control both via switching. With that, the ULN2003 could be eliminated.

The down point is that a major structure redesign should be made, since the NEMA is way bigger.