Truthfully, he wants to build a CNC machine, so the plotter is just a stepping stone. In fact, some of it may be a little much for just a plotter. Other design choices have worked for the plotter ...

Unfortunately, the drag knife blades for CNC routers are pricey — over $100 for a single blade. [Brian] at the Grunblau Design Studio ... that accepts replaceable steel blades for cutting.