[mark] had an interesting idea when looking at all the wiring of a typical 3D printer; Use CAN Bus. There are a lot of wires going to the extruder assembly, and with most designs this thing is flying ...

Early 3D printers usually had a microswitch that let you know when the Z axis was at the zero point. There was usually an adjustment screw so you could tune for just the right layer height. But these ...