Instructables user tuenhidiy wanted to create a new kind of CNC plotter that was unlike nearly all of the others you’ve seen. Rather than use aluminum extrusions or wood, this machine is constructed from various pieces of PVC pipe all cut to exact lengths, hence its name, the “CoreXZ Puzzle Pipe Plotter.”

Electronics wise, the plotter runs on an Arduino Uno loaded with an instance of the ubiquitous GRBL firmware. Stacked on top was a CNC GRBL shield, which has three A4988 stepper motor drivers for delivering current to three NEMA17 motors. 

To assemble this PVC CNC machine, tuenhidiy started by building the lower frame from a plethora of T-joints and connectors along with several inserts for attaching the aluminum rods. The plate at the bottom of the machine glides across the Y axis via a pair of aluminum rods and a set of bearings whereas the perpendicularly placed X axis is stationary and moves in a similar manner using one stepper motor placed to the side. Across from this motor is another one, which manipulates the Z axis vertically. 

After adding a pen and connecting the motors to the shield, tuenhidiy opened the Universal Gcode Platform application and added a few different toolpaths for testing. As shown in the following video, the plotter does a great job at drawing both pictures and text accurately. For more details about this project, check out its tutorial on Instructables.