My friend is a machinist and suggested that all we need to do to add a 4th axis is to make a plate that bolts to the bottom of a 4th stepper, that plate and the stepper will bolt to the table. We then need a cheap mini lathe chuck off ebay, he said he has seen them anywhere from 20-60 dollars and the adapter to attach it to the stepper. Once the stepper is bolted to the table, and the chuck on the adapter your ready to roll! Since you can bolt and unbolt the 4th stepper it gives you functionality from doing large sheets with the 3 axis, or be selective and turning parts like a lathe with all 4 axis. Adding a 4th axis in Mach 3 is a snap as well. Just thought i would throw it out there, pretty cheap upgrade considering it gives you the capabilities of add a 4th axis and using the machine like a mini lathe for wood and plastics.
