Made some progress again towards finishing this design. Its nice having the Z Carriage made in PETG although it took 4 days to print. The overhangs are..  okay, but you don't really see these once the Z axis motor is installed.  This Prusament PETG is really fantastic. I added a cable chain mount and magnets to the base for a detachable dust shoe I still need to design.

Heavily Modified Printers. Left: Wanhao Duplicator Plus. Right: Prusa MK2.5s with Enclosure

These new parts are "Mostly" final versions. There is still a size issue with the cap that covers the X axis lead screw bearing opposite of the motor. The outer diameter is small enough for the Z axis assembly to move fully to the end stop on the left of the machine, but the gap is super close. I fear any dust or material will cause a jam. Printing a cap with a smaller outer diameter should be an easy fix to this.

I had some issues with the stepper motor driver current being too low on the Duplicator Plus X-Axis, resulting in some layer shifting and wasted PETG cable chains.

Various prints of CNC x-axis parts

I'm slightly worried that the cable chains are too small, but we will see how things turn out once the wiring starts. I think they will work. The linear rail seems to work as intended. There is still deflection, but it is not nearly as dramatic without the rail. You cant really see the rail in these pictures, but you can see it in an earlier design post here.  

Next steps will be adding slight tweaks to the Z-Axis carriage. There is an issue with hole depth for the bottom M5 nuts that keep the Z lead screw in place. Easy fix for me is installing 18mm M5 Cap head screws in place of the 16mm originally designed for, but I want to keep the lengths of screws used consistent for when the design gets posted.

Reconstruction of the CNC machine using new PETG parts. Some yellow hatchbox PLA still remain in these photos

Took some time to break down the melted PLA parts to reclaim the linear bearings and other hardware. This was some effort, but there is no way I am throwing out anything I can re-use at this point. I ended up buying twice the linear bearing as I actual need for this CNC, but I would think reclaiming the press fit parts from PLA is going to be easier than PETG. Now if I have to re-print the Z axis assembly, I have the choice to not break down the PETG parts just printed.